JP2003181976A - Laminate, switch, detecting device, joining part, wiring, electrostatic actuator, capacitor, measuring device and radio - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminate for restraining a hillock, a switch, a detecting device, a jointing part, wiring, an electrostatic actuator, a capacitor, a measuring device and a radio. <P>SOLUTION: The laminate has at least a third layer 103 formed on a base 104, a second layer 102 formed on the third layer 103 and a first layer 101 formed on the second layer 102, and the hardness of the second layer 102 is higher than that of the first layer 101. The switch, the detecting device, the jointing part, the wiring, the electrostatic actuator, the capacitor, the measuring device and the radio are manufactured by using this laminate. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminate, a switch,
The present invention relates to a detection device, a joint portion, wiring, an electrostatic actuator, a capacitor, a measuring device, and a wireless device.

[0002]

2. Description of the Related Art Conventionally, an electrostatic relay (Micro Machined Relay, hereinafter also referred to as MMR) using a micromachine technology and a capacitance type sensor are manufactured by a semiconductor process.

For example, the conventional MMR is a journal of the Institute of Electronics, Information and Communication Engineers (Vol. J84-C No. 1 pp. 11-).
16 January 2001) Some of them are introduced in "Development of high frequency MMR". FIG. 22 shows a conventional MMR.
An exploded view of is shown.

This MMR is made up of a glass substrate 2211 and a silicon substrate 2210.
Signal lines 2217 and 2218 and fixed contact 221 are provided on 11.
3, 2214, fixed electrode 221 which also serves as a high frequency ground
Bonding pads 2216 for electrical connection to the outside with wires are formed.

Fixed contacts 2214 and 2213 are provided at the tips of signal lines 2217 and 2218, respectively.

Further, a movable electrode 2220, a movable contact 2227, a return spring 2222 and a bump 2224 are formed on the silicon substrate 2210, and the anchors 222 at two positions are formed.
It is fixed to the glass substrate 2211 at 1.

The movable contact 2227 is provided through an insulating film (not shown) to ensure electrical insulation from the movable electrode 2220.

The voltage applied between the fixed electrode 2212 and the movable electrode 2220 attracts the movable electrode 2220 to the fixed electrode 2212, and the movable contact 2227 contacts the fixed contact 2213 and the fixed contact 2214. The signal line 2218 can be electrically connected.

The movable contact 2227 and the fixed contact 22
It is desirable that the surfaces of 13 and 2214 are smooth in terms of ensuring contact reliability.

These contacts are formed by forming a film by vapor deposition or sputtering, and are made of only Au-based material.

Further, for example, as a conventional capacitance type sensor, there is one as disclosed in Japanese Patent Laid-Open No. 9-178578.

This capacitance type sensor is constituted by anodic bonding a silicon substrate and a fixed substrate such as a glass substrate.

A thin diaphragm is formed on the silicon substrate by etching. Since the silicon substrate is a semiconductor, the diaphragm functions as a movable electrode.

A fixed electrode is formed on the fixed substrate at a position facing the diaphragm, and constitutes a sensor for reading a change in the distance between the movable electrode and the fixed electrode as a capacitance between two poles.

The connection electrode is drawn out from the fixed electrode on the fixed substrate and is electrically joined to the wire bonding pad formed on the semiconductor substrate (hereinafter, such a joint portion is referred to as an interconnection portion, It is abbreviated as the in-cone part.).

It is desirable that the surfaces of these electrodes facing each other are smooth in order to secure a stable electrostatic capacity and in the contact point portion to secure the contact reliability. These electrodes and in-cone parts are formed by forming a film by vapor deposition or sputtering, and are made of a soft metal such as Al.

If the surface of the film formed by the semiconductor process as described above has irregularities, the characteristics of the manufactured device may be affected. Therefore, the surface of the film is preferably smooth.

For example, when there are irregularities on the surface of the contacts of the switch, the electrodes of the capacitance type sensor, the in-cone part, etc., the MMR
In such a case, contact failure or reduction in contact reliability may be caused, and in the capacitance type sensor, capacitance variation or erroneous sensing may occur in the electrode section, and contact failure may occur in the lead section.

[0019]

However, when a product is formed by a semiconductor process, large unevenness exceeding normal unevenness is often generated in the process. This is called hillock.

There are still many unclear points about the mechanism of hillock generation.

Although it has not reached the point where it is physically elucidated both academically and industrially, it has been found that hillocks are particularly apt to occur with metals such as Au and Al. The mechanism of hillock generation is phenomenologically described below.

(Timing of Occurrence of Hillocks) Hillocks are often observed in the subsequent steps rather than immediately after film formation. In particular, it is remarkably observed after the step of applying heat.

(Gas theory) One of the leading theories as a cause of hillocks is a gas mixing theory. The gist of the theory is that the gas mixed inside the film forms hillocks in the process of moving and expanding due to heat and pressure (Fig. 2).
3). FIG. 23 shows a schematic diagram of the mechanism of hillock generation by the gas theory.

For example, in the film formation by the sputtering method, it is known that a large amount of sputtering gas, for example Ar, is mixed in the material to be formed ((a) of FIG. 23).

The gas then expands during the process. Alternatively, the gas accumulated at a plurality of locations is mixed and expanded ((b) of FIG. 23).

During the process of outgassing,
Push away the metal ((c) of FIG. 23).

Many hillocks are observed on the surface of the film formed by sputtering. On the other hand, the deposition method, which is a film forming method that does not use Ar gas, produces a relatively small amount of hillocks.

Considering the difference between sputtering and vapor deposition, it is fully conceivable that gas is one of the factors.

However, the difference in the content of Ar between the two kinds does not linearly match the difference in the amount of hillock generation.

When the Ar content is 1/100, the hillock does not become 1/100. For hillocks,
It is thought that other factors are involved.

In addition, similar to the theory of gas, it can be pointed out that the same phenomenon occurs even with impurities other than gas.

(Stress theory) There is also a stress theory as a mechanism of hillock generation. This stress theory is a theory that metal that has lost its place rises from the surface and becomes a hillock due to the force of expansion and compression. The generation of force may be internal stress during film formation or a thermal process after film formation (FIG. 24). FIG. 24 shows a schematic view of a hillock generation mechanism according to the stress theory.

Generally, the substrate is often heated during film formation in order to obtain uniform film formation and certain characteristics.

In this case, internal stress is generated due to the difference in thermal expansion coefficient between the substrate and the film forming material ((a) of FIG. 24). When the film formation temperature is extremely high, it is assumed that hillocks are observed on the surface immediately after the film formation.

Internal stress is also generated when a high temperature process is performed after film formation. At this time, the stress escape site is the film surface. This is because the open end is similar to the substrate.

That is, a force is applied in the direction of relaxing the stress ((b) of FIG. 24), and the strain for releasing the stress is observed as a hillock on the film surface ((c) of FIG. 24). ).

(Adverse effect of hillocks) In an electrostatic actuator, a capacitive sensor or the like which uses the electrode gap, if the unevenness between the gaps becomes large as compared with the electrode gap distance, a malfunction occurs.

Hillocks can be large enough compared to the spacing and are often found to adversely affect device functionality. The following issues are listed as an example.

(MMR) As described above, in the MMR, if the surface of the contact or the electrode is uneven, contact failure occurs or contact reliability is lowered.

Particularly, in the case of contacts, there are problems such as a decrease in withstand voltage between contacts, a decrease in contact stability, and a decrease in controllability of adhesiveness.

(Electrostatic Capacitance Type Sensor) In the electrostatic capacity type sensor, if the electrode surface or the Incone electrode surface is uneven, as described above, the electrode portion or the lead-out portion is defective.

That is, in the electrostatic capacitance type sensor, initial capacitance / sensitivity variation occurs due to inaccuracies in the distance between the electrodes, and further, there are problems such as reduction in withstand voltage and unstable operation.

Hillocks are not only generated immediately after film formation, but are often generated and grown in the process after film formation.

For example, hillocks may be observed on the metal film immediately after formed by sputtering, vapor deposition, CVD, plating or the like. In addition, it is observed that hillocks are newly generated and grown in the subsequent patterning process and bonding process.

The present invention has been made to solve the above-mentioned problems of the prior art, and the object thereof is to provide a laminated body for suppressing hillocks, a switch, a detector, a joint, wiring, an electrostatic actuator. , A capacitor, a measuring device, and a wireless device.

[0046]

In order to achieve the above object, a laminate according to the present invention has at least a third layer formed on a substrate and a second layer formed on the third layer. And a first layer formed on the second layer, wherein the hardness of the second layer is higher than the hardness of the first layer.

The laminated body according to the present invention is characterized in that the laminated body is formed of a metal.

The laminated body according to the present invention is characterized by being manufactured in a semiconductor process.

The laminate according to the present invention is characterized in that the second layer has a Vickers hardness of 150 or more.

Further, the laminate according to the present invention is characterized in that the second layer contains at least one of Ru, W, Mo, Ir, Os, Ag and Pd as a component.

Further, the laminated body according to the present invention is characterized in that the first layer and the third layer are formed of the same kind of material.

The laminated body according to the present invention is characterized in that the first layer contains at least one of Au, Ni, Ag, Pd, Al, Pt and Rh as a component.

Further, the laminate according to the present invention comprises an adhesion layer formed so as to contact the substrate, and the adhesion of the adhesion layer is formed on the opposite side of the adhesion layer to the substrate. Characterized by being superior to layers.

Further, the laminate according to the present invention comprises a diffusion prevention layer formed so as to come into contact with the adhesion layer or the substrate, and the diffusion prevention layer has a small diffusion coefficient with respect to other layers, or The diffusion coefficient from the other layers to the diffusion prevention layer is small.

Further, the switch according to the present invention is characterized in that the above-mentioned laminated body is used as at least one electric contact.

Further, in the detecting device according to the present invention, the distance between the facing surfaces changes according to the physical quantity, and the detecting means detects the physical quantity based on the change in the distance. Is used.

Further, the detection device according to the present invention is characterized in that it is a capacitance type sensor for detecting the physical quantity based on a change in capacitance due to a change in the distance between the opposing surfaces.

Further, the joint portion according to the present invention is characterized in that it is formed for the purpose of joining to the other joint portion by using the above laminated body.

Further, the wiring according to the present invention is characterized by using the above laminated body.

Further, the electrostatic actuator according to the present invention is characterized in that the above laminated body is used for at least one of the movable electrode and the fixed electrode.

Further, the capacitor according to the present invention is characterized in that at least one of the counter electrodes uses the above laminated body.

Furthermore, the measuring device according to the present invention uses the above-mentioned switch.

Further, the radio device according to the present invention uses the above switch.

Here, in the present specification, forming a layer (herein referred to as a forming layer) on a substrate means not only a case where the forming layer is formed in contact with the substrate, but also a case where the substrate and the forming layer are formed. It also includes the case where an arbitrary number of layers of 1 or more is sandwiched between and.

[0065]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be illustratively described in detail below with reference to the drawings. However, the dimensions of the components described in this embodiment,
Unless otherwise specified, the material, the shape, the relative arrangement, and the like are not intended to limit the scope of the present invention thereto.

Further, in the following drawings, the same numbers are given to the members described in the drawings of the description.

(First Embodiment of Laminate) First, a first embodiment of the laminate according to the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a first embodiment of a laminated body according to the present invention.

As shown in FIG. 1, the laminated body according to the present invention is a laminated body in which three layers are formed on the substrate 104. This laminated body includes a third layer 103 formed on a substrate 104, a second layer 102 formed on the third layer 103, and a first layer 10 formed on the second layer 102.
It consists of 1.

The first layer 101 is made of a material that is softer than the second layer 102 (hereinafter, those having a high hardness are referred to as hard and those having a low hardness are referred to as soft in the present specification). The second layer 102 preferably has a Vickers hardness of 200 or more, or at least 150 or more. Further, the hardness of the third layer 103 may be arbitrary.

The first layer 101 is generally a surface layer not in contact with the substrate, but the present invention is not limited to the case where the first layer is a surface layer.

As the material of the laminated body shown in FIG.
When the layer / second layer / third layer is Au / Ru / Au, a combination having a Vickers hardness of 65/300/65 is possible, which satisfies the condition of the laminated body of the first embodiment.

If the hardness relationship between the first layer 101 and the second layer 102 is maintained, for example, the first layer 101 may be made of Au, Ni, Ag, Pd, Al, Pt and R.
It is sufficient that at least one of h is contained as a component.

If the hardness relationship between the first layer 101 and the second layer 102 is maintained, the second layer 102
May contain at least one of Ru, W, Mo, Ir, Os, Ag and Pd as a component.

For the third layer, any material can be selected in accordance with the design policy of each laminate, but Au, Ag, Al and C may be selected.
The use of u, W, Ir, Mo, and Rh is desirable because it is relatively easy to manufacture. Among them, Au, Ag,
Al and Cu are more preferable because they have high electric conductivity and have a wide range of application for various design purposes.

However, the first layer 10 of the present embodiment.
The materials used for 1, the second layer 102, and the third layer 103 are
The material is not limited to the above materials, and any material may be used as long as the hardness of the second layer 102 is higher than the hardness of the first layer 101 and hillock, electrical conductivity, and adhesion can be achieved at the same time.

Here, FIG. 2 shows generally known numerical values for Vickers hardness and electric conductivity of each material. FIG. 2 is a table showing Vickers hardness and electric conductivity of materials used for the first embodiment of the laminate according to the present invention.

Here, the electrical conductivity is 10% that of copper.
The relative electric conductivity (IACS%) when 0 was shown.

In FIG. 2, there are variations in Vickers hardness for the same type of material due to the difference in the production process of each material.

As shown in FIG. 2, even if the same kind of material is used, the Vickers hardness may vary. Therefore, when making the first layer of the laminate softer than the second layer as in the present invention, it is necessary to form the laminate while considering the hardness of each material.

As described above, when the first layer is made of a material softer than the second layer, the effect of suppressing hillocks can be obtained. The second layer preferably has a Vickers hardness of 200 or more, or at least 150 or more.

Here, a metal laminated body using the laminated body of the first embodiment will be described with reference to FIG. FIG. 3 is a schematic view of a surface state of a metal laminated body using the laminated body of the first embodiment.

The drawing shown in FIG. 3 (a) is a schematic view of a conventional metal laminate and its surface, and the drawing shown in FIG. 3 (b) is the first embodiment of the laminate according to the present invention. It is the schematic of the metal laminated body using the form, and its surface.

In the conventional metal laminated body shown in FIG. 3A, the Au layer 303 is laminated on the glass substrate 301.

In the metal laminate using the first embodiment of the laminate according to the present invention shown in FIG. 3B, the first Au layer 306 is laminated on the glass substrate 301.

In the metal laminate according to the present invention shown in FIG. 3B, the first Ru layer 307 is formed on the first Au layer 306, and the first Ru layer 307 is formed on the first Ru layer 307. The second Au layer 308 is formed.

In FIG. 3B, the first Au layer 30 is formed.
6 corresponds to the third layer 103 shown in FIG. 1, and the first Ru
The layer 307 corresponds to the second layer 102 shown in FIG.
Au layer 308 corresponds to the first layer 101 shown in FIG.

AFM (Atomic Force Micros) is applied to each surface of the metal laminate.
observation was performed. As a result, as shown in the right diagram of FIG.
In the metal laminate using the laminate according to the present invention, generation of hillocks was scarcely observed.

As described above, the first laminated body according to the present invention
According to the embodiment, since the second layer 102 having a hardness higher than that of the first layer 101 is formed, it is possible to effectively prevent the generation of hillocks.

(Second Embodiment of Laminated Body) Next, a second embodiment of the laminated body according to the present invention will be described with reference to the drawings. FIG. 4 is a sectional view of a second embodiment of the laminated body according to the present invention.

As shown in FIG. 4, the laminated body according to the present invention is a laminated body in which the layers formed on the substrate 404 consist of three layers. The stack includes a third layer 40 on a substrate 404.
3 and a second layer 402 formed on the third layer 403.
Then, the first layer 401 formed on the second layer 402 is formed.

The first layer 401 is made of a material softer than the second layer 402. The second layer 402 preferably has a Vickers hardness of 200 or more, or at least 150 or more.

The first layer 401 is generally a surface layer not in contact with the substrate, but the present invention is not limited to the case where the first layer is a surface layer.

Further, the laminated body of this embodiment has the above-mentioned first structure.
The first layer 401 and the third layer 4 in comparison with the laminated body of the embodiment of
The feature is that 03 is always the same material.

That is, in the above-described first embodiment of the laminated body, the first layer 101 and the third layer 103 may be made of the same material or different materials. In the form, the first layer 401 and the third layer 403 are always the same kind of material.

As the material of the laminated body shown in FIG.
The case where the layer / second layer / third layer is Au / Ru / Au is applicable.

As described above, the first layer 401 and the third layer 403
By using the same type of material for and, it is possible to reduce management and production costs.

Since the third layer can be used as the conductive layer, the flexibility of design can be secured.

The first layer 401 and the second layer 40 of this embodiment
The materials of the second and third layers 403 are the same as those of the first layer 10 described in the above description of the first embodiment of the laminate.
The same material as that of the first, second layer 102, and third layer 103 can be used.

However, the first layer 40 of the present embodiment.
The materials used for 1, the second layer 402, and the third layer 403 are
The hardness of the first layer 401 is lower than the hardness of the second layer 402, and the hillock, the electric conductivity, and the adhesiveness are not limited to the materials described in the laminated body of the first embodiment. Any material that can be achieved may be used.

As described above, the first layer 401 is replaced with the second layer 402.
If it is made of a softer material, the effect of suppressing hillocks can be obtained as in the first embodiment.

(Third Embodiment of Laminate) Next, a third embodiment of the laminate according to the present invention will be described with reference to the drawings. FIG. 5: is sectional drawing of 3rd Embodiment of the laminated body which concerns on this invention.

Third of the laminate according to the present invention shown in FIG.
This embodiment is a laminated body provided with a fourth layer 504, which has better adhesion to the substrate 505 than the third layer 503.

As shown in FIG. 5, in the third embodiment of the laminated body according to the present invention, the fourth layer 504 formed on the substrate 505 and the third layer formed on the fourth layer 504. Layer 503 and second layer 50 formed on this third layer 503
2 and a first layer 501 formed on the second layer 502.

The first layer 501 is made of a material softer than the second layer 502. The second layer 502 preferably has a Vickers hardness of 200 or more, or at least 150 or more. Also,
The hardness of the third layer 503 may be arbitrary. Further, the third layer 503 may be made of the same material as the first layer 501 or any kind of material.

The first layer 501 is generally a surface layer not in contact with the substrate, but the present invention is not limited to the case where the first layer is a surface layer.

The first layer 501 and the second layer 50 of this embodiment
The materials of the second and third layers 503 are the same as those of the first layer 10 described in the above description of the first embodiment of the laminated body.
The same material as that of the first, second layer 102, and third layer 103 can be used.

The material of the fourth layer 504 is the second
Any material that can be used for the material of the layer 502 can be used. However, in the case of the present embodiment, the material of the second layer 502 and the material of the fourth layer 504 do not have to be the same kind. Furthermore, Cr, Ti, or the like can be used as the material of the fourth layer 504.

Further, the materials used for the first layer 501, the second layer 502, the third layer 503, and the fourth layer 504 of this embodiment are the same as the materials described for the laminated body of the first embodiment. The hardness of the first layer 501 is not limited to the above.
If the hardness is lower than 2, it may be any material that can achieve both hillock, electrical conductivity, and adhesion.

The fourth layer 504 is an adhesion layer, and as described above, the adhesion to the substrate 505 is superior to that of the third layer 503. Therefore, when the adhesion between the third layer and the substrate is not sufficient for practical use, it can be improved by inserting the adhesion layer which is the fourth layer.

For example, if a gap is generated between the substrate and the metal due to poor adhesion, no matter how much the surface hillock is prevented, the effect may not be enjoyed.

Obtaining a sufficient degree of adhesion is important for sufficiently exerting the hillock reducing effect.

Providing the fourth layer 504 as shown in FIG. 5 does not significantly affect hillock reduction, conductivity, etc., so that in the third embodiment, the laminate of the first embodiment is used. Alternatively, the hillock reducing effect and the conductivity are not reduced as compared with the laminated body of the second embodiment.

Specifically, in the above-described third embodiment, Au / Ru / A is used as the first layer / second layer / third layer / fourth layer.
u / Ru, Au / Ru / Ag / W, Au / Ru / Au /
Various combinations such as Cr are applicable. Both are 4th
A material is selected for the layer 504 in consideration of adhesion to the substrate 505.

As described above, according to the third embodiment of the laminated body of the present invention, it is possible to obtain the same effects as those of the above-described first and second embodiments, and to apply the same to the substrate. Since the adhesiveness can be improved, the characteristics of the laminated body can be further improved.

(Fourth Embodiment of Laminate) Next, a fourth embodiment of the laminate according to the present invention will be described with reference to FIG. FIG. 6 is a sectional view of a fourth embodiment of the laminated body according to the present invention.

As shown in FIG. 6, the structure of the laminated body according to the fourth embodiment of the present invention is substantially the same as that of the above-mentioned third embodiment.

That is, in the fourth embodiment of the laminated body according to the present invention shown in FIG. 6, the adhesiveness to the substrate 605 is the third.
This is a stacked body provided with a fourth layer 604 superior to the layer 603.

As shown in FIG. 6, in the fourth embodiment of the laminated body according to the present invention, the fourth layer 604 formed on the substrate 605 and the third layer formed on the fourth layer 604. Layer 603 and second layer 60 formed on this third layer 603
2 and a first layer 601 formed on the second layer 602.

The first layer 601 is made of a material softer than the second layer 602. The second layer 602 has a Vickers hardness of preferably 200 or more, or at least 150 or more. Also,
The hardness of the third layer 603 may be arbitrary. The third layer 603 may be made of the same material as the first layer 601.

The first layer 601 is generally a surface layer not in contact with the substrate, but the present invention is not limited to the case where the first layer is a surface layer.

The first layer 601 and the second layer 60 of this embodiment
The materials of the second and third layers 603 are the same as those of the first layer 10 described in the above description of the first embodiment of the laminated body.
The same material as that of the first, second layer 102, and third layer 103 can be used.

However, the first layer 60 of the present embodiment.
The materials used for the first, second layer 602 and third layer 603 are
The material is not limited to the materials described for the laminated body of the first embodiment, but if the hardness of the first layer 601 is lower than the hardness of the second layer 602, hillocks, electrical conductivity, and adhesion are compatible. Any material capable of achieving

The fourth layer 604 is an adhesion layer, and as described above, the adhesion to the substrate 601 is superior to that of the third layer 603. Furthermore, the present embodiment is characterized in that the fourth layer 604 is always made of the same material as the second layer 602.

The fourth of the laminate according to the present invention shown in FIG.
As the structure of the embodiment, for example, first layer / second layer / third layer
Au / Ru / Au / Ru / substrate corresponds to layer / fourth layer / substrate.

Therefore, according to the fourth embodiment of the laminated body of the present invention, it is possible to obtain the same effects as those of the above-mentioned third embodiment of the laminated body of the present invention, and it is possible to obtain the second effect.
By using the same material for the layer 602 and the fourth layer 604, management and production costs can be reduced.

Further, since the fourth layer 604 can be used as a conductive layer, flexibility of design can be secured.

(Fifth Embodiment of Laminate) Next, a fifth embodiment of the laminate according to the present invention will be described with reference to FIG. FIG. 7: is sectional drawing of 5th Embodiment of the laminated body which concerns on this invention.

As shown in FIG. 7, the fifth embodiment of the laminate according to the present invention is the fifth embodiment formed on the substrate 706.
Layer 705 and fourth layer 7 formed on this fifth layer 705
04, and a third layer 703 formed on the fourth layer 704.
And a second layer 702 formed on the third layer 703,
The first layer 701 is formed on the second layer 702.

The first layer 701 is made of a material softer than the second layer 702. Further, the second layer 702 has a Vickers hardness of preferably 200 or more, or at least 150 or more. Also,
The hardness of the third layer 703 may be arbitrary. Further, the third layer 703 may be made of the same material as the first layer 701 or a different material.

The first layer 701 is generally a surface layer not in contact with the substrate, but the present invention is not limited to the case where the first layer is a surface layer.

The fifth layer 705 is a layer having a better adhesion to the substrate 706 than the fourth layer 704. On the other hand, the fourth layer 70
The material of No. 4 has a lower diffusibility of the material into the third layer 703 than the material of the fifth layer 705. Also, the fourth layer 70
4 may be the same material as the second layer 702 or different materials.

The first layer 701 and the second layer 70 of this embodiment.
The materials of the second and third layers 703 are the same as those of the first layer 10 described in the above description of the first embodiment of the laminated body.
The same material as that of the first, second layer 102, and third layer 103 can be used.

However, the first layer 70 of the present embodiment.
The materials used for the first, second layer 702 and third layer 703 are
The material is not limited to the material described in the laminated body of the first embodiment, and if the hardness of the first layer 701 is lower than the hardness of the second layer 702, hillock, electric conductivity, and adhesion are compatible. Any material capable of achieving

The material of the fourth layer 704 is a material in which the diffusion coefficient of the material of the third layer 703 is smaller than the diffusion coefficient of the material of the fifth layer 705 of the material of the third layer 703. Further, the material of the fifth layer 705 is a material that has better adhesion to the substrate 706 than the fourth layer 704.

For example, comparing Ru and Cr, since Cr has excellent adhesion to the substrate, in the third embodiment, the first layer / second layer / third layer / fourth layer is Au /
Ru / Au / Cr was taken up.

However, Cr strongly diffuses into Au, and A
A substance called uCr is formed. In order to prevent this, in the present embodiment, Au of the third layer 703 and Cr of the fifth layer 705 are used.
And a layer of another material, for example, a fourth layer 704 made of Ru, is sandwiched as a diffusion prevention layer.

That is, in the fifth embodiment of the laminated body according to the present invention, for example, the first layer / second layer / third layer / fourth layer / fifth layer is Au / Ru / Au / Ru / An example is Cr.

As described above, in the fifth embodiment of the laminated body according to the present invention, the fifth layer is a layer excellent in adhesiveness to the substrate, so that the fifth embodiment has the same structure as the third embodiment. It is possible to obtain substantially the same effect as the laminated body. However, the fourth layer 70
4 and the substrate 706 have high adhesion, the fifth layer 705
Can be omitted.

Furthermore, according to the fifth embodiment of the laminated body of the present invention, the diffusion of the material between the layers can be prevented.

In addition, like the laminated bodies of the above-described first to fifth embodiments, in the present embodiment, the first layer 70 is used.
The hardness of 1 is made softer than the hardness of the second layer 702.

As a result, the number of hillocks generated can be reduced. That is, the number of hillocks per unit area can be reduced.

As described above, the hardness of the first layer is set to the second hardness as in the laminated body of the above-described first to fifth embodiments.
The size of the hillock can be reduced by making it softer than the hardness of the layer. That is, the height and diameter of each hillock can be reduced.

Further, as the material of the fourth layer 704 for preventing the diffusion of the material, for example, platinum metal and its alloys can all be used. Other than that, W, Mo, N
Materials such as i can also be used. In addition, the role and characteristics of the diffusion prevention layer are that the element contained in the diffusion prevention layer does not diffuse into the layer formed on the diffusion prevention layer, and the element contained in the substrate (such as Na has a high mobility). It is not possible to transmit a substance) and, when an adhesive layer is used, not to transmit a component of the adhesive layer.

Specifically, for example, in the fifth embodiment, Cr has a large diffusion coefficient into Au and forms a compound of Au and Cr, and Na ions from the substrate are removed by Au.
Permeate to the side.

As a countermeasure, by sandwiching Ru between Au and Cr, Cr does not diffuse into Au.

In this case, Ru functions as a diffusion prevention film. Also, since the diffusion coefficient of Ru into Au is low, R
u itself also has a characteristic that it is difficult to diffuse into Au.

Further, impurity ions such as Na and K exist on the glass substrate and may diffuse from the surface of the substrate. Ru has an effect of suppressing diffusion of these impurity ions.

Furthermore, since Ru has a certain degree of adhesion to glass and SiO ₂ , it is possible to form Ru directly on the substrate without using Cr and use the Ru layer as a diffusion prevention layer and adhesion layer. Is.

Further, as in the laminates of the above-described first to fifth embodiments, the hardness of the first layer 701 is made softer than the hardness of the second layer 702, so that the metal surface is mechanically strengthened. In such a case, since a metal having a high hardness is used as the intermediate layer, the apparent hardness of the metal surface is increased.

In each of the above embodiments of the laminate,
Although the hardnesses of the first layer and the second layer are changed, the second layer may be harder than the first layer, and the first layer and the second layer may be the same kind of material. For example, in Au-Ag shown in FIG. 2, the Vickers hardness varies from 29 to 185 depending on the composition ratio. In such a material, for example, Au-Ag having a Vickers hardness of 29 is used as the first layer, and Au-Ag having a Vickers hardness of 185 is used as the second layer. The relationship of hardness of the two layers can be satisfied. Further, Pt is the temperature at the time of formation,
Since the hardness changes depending on the pressure and the forming method, the hardness relationship between the first layer and the second layer can be satisfied only with Pt. As described above, when the same type of material is used for the adjacent layers, the manufacturing process of the laminate of the present embodiment can be simplified, and the management cost and the manufacturing cost can be reduced.

Further, in each of the above embodiments of the laminated body, the number of layers on the substrate was 5 layers at the maximum, as shown in FIG. 7, but the present invention is limited to such a case. However, if the first layer is softer than the second layer, the number of layers sandwiched between the substrate and the second layer is not particularly limited, and the number may be arbitrary. .

However, if the number of layers between the substrate and the second layer is small, the manufacturing process can be simplified and the manufacturing cost can be reduced as compared with the case where the number of layers is large.

(Manufacturing Process of the Laminated Body) When manufacturing the laminated body, depending on the material thereof, for example, each of the first layer to the fifth layer is formed by PVD (Physical Vapor) including vacuum deposition, sputtering, etc. Depo
production), or CVD
(Chemical Vapor Deposition
n), may be manufactured by an epitaxial manufacturing method, may be manufactured by plating including electroplating, electroless plating, hot dipping, etc., or by other appropriate methods. However, the manufacturing method is not limited.

Therefore, when PVD, CVD, an epitaxial manufacturing method or the like is used, the laminated body of each of the above embodiments is subjected to a designing process, a mask manufacturing process, a wafer manufacturing process,
It can be manufactured in the film forming process of the wafer processing process in the semiconductor process including the wafer processing process, the assembly process, the inspection process and the like.

Therefore, when the device described later is manufactured as a semiconductor device, the laminated body can be easily manufactured.

(Application Example of the Laminated Body) Next, the case where each embodiment of the laminated body described above is applied to various structures and devices will be described.

(One Embodiment of Switch) First, an electrostatic relay as a switch will be described as a device to which the above-mentioned laminated body is applied. One embodiment of the electrostatic relay as a switch according to the present invention uses the above-described first to fifth embodiments of the laminated body for each part constituting the electrostatic relay.

FIG. 8 is a perspective view of an embodiment of an electrostatic relay as a switch according to the present invention.

In this electrostatic relay, a movable substrate 820 is provided on the upper surface of a fixed substrate 810 made of a glass substrate.

A fixed electrode 812 is formed on the upper surface of the fixed substrate 810.
And fixed contacts 813 and 814 are formed.

For the fixed contacts 813 and 814, the above-described first to fifth embodiments of the laminated body are used.

Further, at least one of the fixed contacts 813 and 814 may use the above-described first to fifth embodiments of the laminated body.

The surface of the fixed electrode 812 is covered with an insulating film 815. The fixed electrode 812 is a wiring pad 816.
a, 816b, 816c, 816d.

Further, the fixed contacts 813 and 814 are connected to the electrode pads 817 via wirings 817a and 818a, respectively.
And 818.

These wirings 816a, 816b, 816
At least one of c, 816d, 817a, and 818a, the first to fifth embodiments of the laminate described above.
May be used.

Further, the movable substrate 820 is provided with a supporting portion 821.
It is fixed to the fixed substrate 810 via a and 821b, and the joints 821a and 811a form an electrical joint and are connected to the electrode pad 811b.

Joining portion 811 forming this electrical joining portion
The first to fifth embodiments of the laminate described above may be used for a.

A movable contact 828 is formed on the surface of the movable electrode 825 of the movable substrate 820 facing the fixed substrate 810. When the movable substrate 820 is bent by electrostatic attraction,
The movable contact 828 abuts the fixed contacts 813 and 814.

For the movable contact 828, the above-described laminated body of the first to fifth embodiments may be used.

Here, the embodiment of the above-mentioned laminated body is shown in FIG.
A case will be described with reference to the drawings in which it is applied to the fixed contacts 813 and 814 or the movable contact 828 (hereinafter, simply referred to as contacts) of the electrostatic relay shown in FIG.

When hillocks are generated at the contacts, the breakdown voltage between the contacts is lowered, the contact stability is lowered, and the controllability of the adhesiveness is lowered.

Therefore, as shown in FIG. 9, in the first embodiment of the contact using the laminated body according to the present invention, the structure of the contact is the same as in the first to fifth embodiments of the laminated body described above. Morphological structure. FIG. 9 is a cross-sectional view of a first embodiment of a contact using the laminated body according to the present invention.

The structure of the contact shown in FIG. 9 is the structure of the fifth embodiment of the above-mentioned laminated body according to the present invention.

That is, the Cr layer 90 is formed on the substrate 906.
5, a second Ru layer 904, a second Au layer 903, a first Ru layer 902, and a first Au layer 901 are sequentially formed.

The Cr layer 905 has a thickness of 0.01 μm or more, a value of 0.
The thickness is 1 μm or less. Second Ru layer 904
Has a thickness of 0.01 μm or more and 0.1 μm or less.

The second Au layer 903 has a thickness of 0.2 μm or more,
The thickness is 1.3 μm or less. First Ru layer 90
2 has a thickness of 0.2 μm or more and 0.4 μm or less. The first Au layer 901 has a thickness of 0.2 μm or more and 0.4
The thickness is less than μm.

Generally, the thicker the second layer, the greater the effect of preventing hillocks. Also, the first layer, the third
The thinner the layer, the smaller the number of hillocks and the smaller the size of the hillocks.

Therefore, the thickness of each layer forming the contact is not limited to the above thickness, and the optimum value of the film thickness of each layer is determined from the total layer thickness required for each laminate. It is desirable to go.

Next, a second embodiment of the contact using the laminate according to the present invention will be described with reference to FIG.
In the second embodiment of the contact using the laminate according to the present invention, the structure of the contact is the same as that of the above-described embodiment of the laminate as in the first embodiment. FIG. 10 is a sectional view of a second embodiment of a contact using the laminated body according to the present invention.

The second embodiment of the contact using the laminate according to the present invention shown in FIG. 10 is a contact to which the first embodiment of the laminate according to the present invention described above is applied.

That is, the contact of the second embodiment is such that the Al layer 1003, the Ru layer 1002, the Au layer are formed on the substrate 1004.
Layers 1001 are sequentially stacked.

Here, the reason why Al is used instead of Au on the substrate 1004 is that Al is used in place of expensive Au to achieve a cost reduction effect. Generally, it is said that Au or Al easily forms an alloy, but since the intermediate layer Ru also has the effect as a diffusion prevention film this time, the Al film 1003 diffuses into the Au film 1001 and the contact portion of the contact is formed. It does not change the properties of Au.

In the first to second embodiments of the contact described above, as the structure of the contact, an example using the laminate of the first embodiment and the laminate of the fifth embodiment has been described. However, the contact using the laminated body according to the present invention is not limited to such a case, and the structure of the contact is similar to that of the second embodiment, the third embodiment or the fourth embodiment described above. A laminated body may be used.

As described above, since any one of the above-described first to fifth embodiments is used for the contact, it is possible to suppress the generation of hillocks, which greatly contributes to the improvement of the reliability of the contact. can do. This is because the contact stability and the withstand voltage are improved, and the extra margin can be used as a design margin.

That is, in the contacts of this embodiment, the distance between the contacts can be controlled with high precision, so that the design of the breakdown voltage between the contacts is facilitated and the breakdown voltage characteristics can be improved.

Further, in the contact of this embodiment, a material having a low hardness can be arbitrarily used on the outermost surface, and the contact reliability is improved.

A material having a low hardness often has a low contact resistance and is suitable for repeating a stable contact operation, so that it is effective in improving the contact stability of the contact and reducing the contact resistance.

Adhesion is often a problem at the contacts. In this case, it is necessary to design the separating force according to the adhesiveness, but if the adhesive force is not stable, the design is difficult.

In the contact of this embodiment, since the adhesiveness is easy to estimate and is stable on the surface of which the flatness is secured by the reduction of hillocks, the adhesiveness controllability can be improved.

Further, in the contact of this embodiment, since a hard substance is sandwiched between soft substances, the apparent hardness can be improved.

However, the contact using the laminated body of the present invention is not limited to the contact of such a relay, but can be applied to a portion other than the contact of the relay. For example, the contact using the laminated body of the present invention is not limited to the contact of a relay, but can be applied to a contact switch.

Next, a method of manufacturing the electrostatic relay having the structure shown in FIGS. 8 to 10 will be described. Figure 11
FIG. 11 is a manufacturing process diagram of the electrostatic relay shown in FIGS. 8 to 10.

First, the glass substrate 81 shown in FIG.
As shown in FIG. 11B, a fixed electrode 812 and fixed contacts 813 and 814 are formed on 1c.

At the same time, wirings 816a, 817a, 8
18a, 819a and connection pads 816, 817,
818 and 819 are formed, respectively. Then, by forming an insulating film 815 on the fixed electrode 812, as shown in FIG.
The fixed substrate 810 shown in (c) is completed.

On the other hand, as shown in FIG. 11D, in order to form a gap between contacts on the lower surface of the SOI wafer 8100 composed of the silicon layer 8101, the silicon oxide layer 8102 and the silicon layer 8103 from the upper surface side, for example, silicon is used. Wet etching is performed by TMAH using the oxide film as a mask to form a supporting portion 821 and a protruding portion 824 protruding downward as shown in FIG.

Then, as shown in FIG. 11F, after forming the insulating film 827, the movable contact 828 is formed.

Next, as shown in FIG. 11G, the SOI wafer 8100 is bonded and integrated with the fixed substrate 810 by anodic bonding.

Then, as shown in FIG. 11 (h), SO
A silicon oxide layer 810, which is an oxide film, is formed on the upper surface of the I wafer 8100 by an alkali etching solution such as TMAH or KOH.
Etch to 2 to thin.

Further, the silicon oxide layer 8102 is removed with a fluorine-based etching solution to expose the silicon layer 8103, that is, the movable electrode 825, as shown in FIG. 11 (i).

Then, die-cutting etching is performed by dry etching using RIE or the like, and the slits 825a, 82
5b is formed and the first and second beam portions 822 and 823 are cut out to complete the movable substrate 820.

The fixed substrate 810 is a glass substrate 811.
Not limited to c, it may be formed of a single crystal silicon substrate having at least its upper surface covered with an insulating film.

Next, the operation of the electrostatic relay having the above structure will be described with reference to FIG. FIG. 12 is a schematic diagram of the operation of the electrostatic relay shown in FIGS. 8 to 11.

In a state where no voltage is applied between the fixed electrode 812 and the movable electrode 825 and no electrostatic attractive force is generated,
As shown in FIG. 12A, since the first beam portion 822 is not elastically deformed and maintains the state in which the first beam portion 822 extends horizontally from the support portion 821, the movable substrate 820 faces the fixed substrate 810 at a predetermined interval. Therefore, the movable contact 828 is the same as the fixed contact 81.
It is separated from 3, 814.

Here, the fixed electrode 812 and the movable electrode 82
When a voltage is applied between the two to generate an electrostatic attractive force, the first beam portion 822 elastically deforms, and the movable substrate 820 moves to the fixed substrate 81.
It approaches 0.

As shown in FIG. 13, the electrostatic attractive force tends to increase as the distance between the electrodes decreases. Figure 13
It is a graph which is applied to the electrostatic relay shown by FIGS. 8-12 and which shows the relationship between an electrostatic attraction and the distance between electrodes.

Then, the fixed substrate 810 and the movable substrate 82.
It is designed so that when 0 approaches the fixed substrate 810 until it abuts, the electrostatic attractive force acting between the fixed electrode 812 and the movable electrode 825 rapidly increases.

Then, the movable substrate 820 has the movable electrode 82.
5 is adsorbed on the fixed electrode 812. As a result, FIG.
As shown in (b), the movable contact 828 has a fixed contact 81.
Closed on 3,814.

Then, the movable contact 828 is replaced by the fixed contact 81.
12 (c), the second beam portion 823 bends in addition to the first beam portion 822, and the movable electrode 825 covers the fixed electrode 812 as shown in FIG. 12C.
Is adsorbed on.

Therefore, when the movable electrode 825 around the movable contact 828 is attracted to the fixed electrode 812, the fixed contact 813, 814 is fixed to the movable contact 828 via the second beam portion 823.
Pressed against. For this reason, one-sided contact does not occur, and contact reliability is improved.

At this time, the first and second beam portions 822 and 823 are formed.
Is a force pulling the movable electrode 825 upward, an electrostatic attractive force between the movable electrode 825 and the fixed electrode 812 through the insulating film 815, and a drag force from the surface of the insulating film 815, respectively, Fs1 and
If Fs2, Fe, Fn have the following relationships,
Spring coefficient of second thin plate beam portions 822 and 823, movable electrode 82
It is possible to reduce Fn and Fs1 by designing the initial gap between the No. 5 and the fixed electrode 812, the thickness of the contact point, and the like, and to suppress the decrease in Fs2, that is, the contact load (from the ideal model).

[0211]

[Equation 1]

After that, the fixed electrode 812 and the movable electrode 82
When the applied voltage between 5 is removed, the first and second beam portions 822,
Not only the elastic force of 823 but also the elastic force associated with the deformation in the vicinity of the convex portion 824 can act as the contact opening force.

Therefore, even if adhesion, welding or the like occurs between the contacts, it is possible to surely separate the contacts. Then, after the contacts are separated, the movable substrate 820 is attached to the first beam portion 8
The elastic force of 22 restores the original position.

Thus, in this embodiment, the movable substrate 8 is
The entire 20 is formed of a single silicon wafer, and is formed so as to have left-right point symmetry and sectional line symmetry. Therefore, the movable electrode 825 is unlikely to be warped or twisted. Therefore, it is possible to effectively prevent the inoperability and the variation in the operation characteristics, and it is possible to secure the smooth operation characteristics.

As described above, in the electrostatic relay according to the present embodiment, at least one of the movable electrode, the fixed electrode, the contact, etc. has the same structure as that of the first to fifth embodiments of the present invention. By using the laminated body, it is possible to obtain the same effects as those of the above-described embodiment of the contact, the embodiment of the actuator described later, and the embodiment of the joint portion described later.

(Application Example to Capacitance Type Sensor) Next, as an application example of the above-mentioned laminated body, a case of application to a capacitance type sensor as a detecting device according to the present invention will be described. Examples of physical quantities measurable by the capacitance type sensor include acceleration, pressure, angular velocity, electric field and the like.
FIG. 14 is a sectional view of an embodiment of a capacitance type sensor as a detection device according to the present invention.

One embodiment of the capacitance type sensor as the detection device according to the present invention is the movable electrode 1403 and the fixed electrode 14.
05 and.

Then, the movable electrode 1403 and the fixed electrode 14
The laminated body of the first to fifth embodiments described above is used for at least one of the electrodes of No. 05.

In the capacitance type sensor of this embodiment, both the movable electrode 1403 and the fixed electrode 1405 may be a laminated body of the same embodiment or may be a laminated body of different embodiments.

In the capacitance type sensor of this embodiment, the concave portion 1406 formed in the semiconductor substrate 1401 anodically bonded to the fixed substrate 1402 forms a pressure detecting gap (sensor gap), and the gap is sandwiched therebetween. Fixed electrode 1405
And the movable electrode 1403 face each other.

Atmosphere is introduced into the recess 1406 through the wiring groove 1404.

The pressure to be measured is applied to the movable electrode (diaphragm) 1403. The movable electrode (diaphragm) 1403 is vertically displaced (vibrated) according to the measured pressure applied.

By changing the gap between the movable electrode 1403 and the fixed electrode 1405, the movable electrode 1403 and the fixed electrode 1405 are changed.
3 and the electrostatic capacitance C between the fixed electrode 1405 changes.

This change in the capacitance C or the change in the reciprocal 1 / C of the capacitance C (generally, the reciprocal 1 / C is used as the sensor output) becomes a signal representing pressure in the capacitance measuring circuit. To be converted.

The physical quantity detected by the detection device according to the present invention is not limited to the above-mentioned physical quantity, but may be any physical quantity as long as it can be detected by utilizing the change in the interval between the electrodes. It may be.

As described above, since the capacitance sensor of this embodiment uses at least one of its electrodes, one of the first to fifth embodiments of the above-mentioned laminated body, It is possible to limit the generation of hillocks in the electrodes, accurately detect the electrostatic capacitance, and accurately detect the physical quantity to be detected.

That is, since the capacitance type sensor of this embodiment can make the distance between the electrodes uniform and stable,
The accuracy of capacitance can be improved, and sensitivity can be enhanced and stabilized.

Further, in the capacitance type sensor of this embodiment, variations among the elements are suppressed.

However, the detection device using each of the embodiments of the laminated body according to the present invention is not limited to the capacitance type sensor as described above, and the laminated body may be applied to various other detection devices. Can be used.

(Application Example to Joining Section) Next, as an application example of the above-mentioned laminated body, a case where it is applied to a joining section will be described with reference to the drawings. FIG. 15 is a schematic view of an embodiment of the joint portion according to the present invention.

That is, a joining portion for performing mechanical joining is formed on each of the surfaces formed for the purpose of joining.

In the present embodiment, this first joint portion 150 is used.
No. 3, 1505 and any one of the second joint portions 1504, 1506, the first to fifth embodiments of the above-described laminated body.
The embodiment of is applied.

For example, as shown in FIG. 15, second bonding portions 1504 and 1506 are formed on the glass substrate 1502.

Further, as shown in FIG. 15, first bonding portions 1503 and 1505 are formed on the silicon substrate 1501.

The first joint portions 1503 and 1505 and the second joint portion
The joints 1504 and 1506 of are made of Au,
The first joint 150 by applying heat to both joints
3, 1505 and the second joint portions 1504 and 1506 are joined together by forming a metal bond. This kind of joint is Au
-It is called Au junction.

In Au-Au joining, smoothness of the joining surface is required to ensure stable joining.

Therefore, if the first to fifth embodiments of the laminated body are used for the joint portion as in the present embodiment, the generation of hillocks can be suppressed, and the joint uniformity and the yield can be improved. Can be planned. Further, since the joint surface forms a uniform smooth surface, there is an effect that the thickness of the Au layer can be reduced.

Further, the first to fifth embodiments of the laminated body
The joint part to which the embodiment of the present invention is applied is not limited to the above-mentioned joint part, and can be applied to all the parts that require the uniformity of the interval at the time of joining.

(Joint Part in Capacitance Type Sensor) Here, the joint part of the capacitance type sensor will be described as an example of the joint part. For example, as shown in FIG. 16, in the capacitance type sensor, the fixed substrate 1610 and the semiconductor substrate 1620 are anodically bonded. FIG. 16 is a schematic perspective view of a capacitance type sensor to which an embodiment of the joint portion according to the present invention is applied.

After the fixed substrate wafer having many sensor portions and the semiconductor substrate are anodically bonded, the wafer is divided into individual sensor chips by dicing. At this time, the portion of the fixed substrate 1610 located above the step portion 1624 of the semiconductor substrate 1620 is also cut off by dicing.

The connecting electrodes 1612 and 1632 are arranged so that the connecting electrodes 1612 and 1632 do not come into contact with the side surfaces of the wiring groove 1623.
The width is slightly narrower than 3.

When the fixed substrate 1610 and the semiconductor substrate 1620 made of silicon are anodically bonded, these connecting electrodes 16 are connected.
12, 1632 interconnection pad 161
2a and 1632a are pressure-bonded in the vertical direction.

As a result, the fixed electrode 1611 and the fixed electrode wire bonding pad 1631 are electrically connected.

Therefore, in the capacitance type sensor shown in FIG. 16, the interconnection pad 1612 is used.
a and 1632a are joint parts (incone part) according to the present invention.
Will be one embodiment.

Considering, for example, a semiconductor process, when several hundreds to several thousands of elements are simultaneously bonded in the wafer surface, a different electric field applied to each in-conc portion causes a defective bonding.

Therefore, according to the joint portion of the present embodiment, since the hillock is prevented, the accuracy of the distance between the electrodes in the in-cone portion is improved, so that the yield in the joint can be improved.

According to the joint portion of this embodiment, the crushing margin of the in-cone electrode (joint portion) of each element arranged in the wafer surface can be made uniform.

Therefore, according to the joint portion of the present embodiment, the in-cone resistance (resistance of the joint portion) is stabilized,
The characteristics as an element can also be stabilized.

(Application Example to Wiring) Next, as an application example of the above-mentioned laminated body, a case where it is applied to wiring will be described.
FIG. 17 is a cross-sectional view of one embodiment of the wiring according to the present invention using the laminated body according to the present invention.

FIG. 17A shows a single layer wiring.
(B) shows multilayer wiring. In addition, in (a) and (b) of FIG. 17, the lower diagram is a diagram showing the conventional wiring when the laminated body according to the present invention is not used, and the upper diagram is
It is a figure which shows the wiring using embodiment of the laminated body which concerns on this invention.

As shown in the upper diagram of FIG. 17A,
One embodiment of the wiring according to the present invention is a laminated wiring in which a wiring layer 1702 is formed on a substrate 1701 and an insulator 1703 is further formed on the wiring layer 1702. The insulator 1703 may be replaced by an atmosphere.

In addition, as shown in the upper diagram of FIG. 17B, one embodiment of the wiring according to the present invention is an insulating layer 1703.
A second wiring layer 1704 and a second insulating layer 17
05 is formed.

The second insulating layer 1705 may be replaced by an atmosphere.

Then, the wiring layer 1702 and the second wiring layer 1
For the layer 704, the above-described first to fifth embodiments of the laminated body are used.

Further, as shown in the lower diagrams of FIGS. 17A and 17B, in the conventional wiring, the wiring layers 1707, 1 are used.
At least one hillock 1706 was generated in 708.

Then, for example, as shown in the schematic diagram of the lower part of FIG. 17A, when hillocks 1706 are generated in the wiring layer, the hillocks cause cracks in the insulating layer, the distance between the metal wirings is shortened, and the withstand voltage characteristic is reduced. Is reduced. Further, if a crack grows to form a gap between the hillock and the insulating layer, metal powder will enter into the gap and the withstand voltage characteristic will deteriorate.

Therefore, in the wiring of this embodiment, the wiring layer 1
Wiring layers were formed on the second wiring layer 704 and the second wiring layer 1704 by using the laminated body of the above-described first to fifth embodiments.

As described above, by forming the wiring on the wiring layer 1702 and the second wiring layer 1704 by using the laminated body of the first embodiment to the laminated body of the fifth embodiment, for example, a laminated wiring can be obtained. An insulating film is formed between the metals, but if there is no hillock at this time, the capacitance between wirings, the charging property, and the short-circuit prevention property can be easily improved. Furthermore, uniform characteristics can be obtained over the entire wiring.

A bridge-shaped wiring is formed even with a three-dimensional wiring that does not use an insulating layer, but the same effect can be obtained in this case as well.

That is, according to the wiring of this embodiment, the characteristics of the entire circuit can be stabilized by keeping the distance between the wirings constant.

Also, in the case of a single-layer wiring or a multi-layer wiring in which an insulating material is arranged on the wiring, it is possible to prevent deterioration of the insulation due to hillocks.

In addition, the wiring of this embodiment is effective in improving the withstand voltage and insulating property between wirings in a multilayer wiring.

As a side effect of improving the withstand voltage, the wiring of this embodiment can form a thinner insulating layer without hillocks unless the withstand voltage characteristics need to be improved, as a side effect. There is an advantage that the density of can be increased.

The hillock-like gap easily causes erosion due to the wiring being exposed to a chemical or an atmosphere. If the wiring is eroded, the electrical characteristics of the wiring are deteriorated, and thus the element durability is also deteriorated.

However, the wiring of the present embodiment improves the generation of the gap by preventing the hillocks, so that the erosion of these can be prevented.

Here, the wiring according to the present invention is not limited to the case where there is one or two wiring layers, as shown in FIG. 17, and the number of laminated layers is not particularly limited. It may have any number of layers.

(Example of Application to Electrostatic Actuator) Next,
As an application example of the above-mentioned laminated body, a case where it is applied to an electrostatic actuator will be described. FIG. 18 is a schematic view of an embodiment of the electrostatic actuator according to the present invention using the laminate according to the present invention. In the following description, an electrostatic actuator will be described, but the actuator according to the present invention is not limited to the electrostatic actuator and can be applied to other actuators.

The electrostatic actuator of this embodiment is shown in FIG.
8 and at least one of the fixed electrode 1802 on the substrate 1803.
The laminated body according to any of the embodiments to the fifth embodiment is used.

In the electrostatic actuator of this embodiment, both the movable electrode 1801 and the fixed electrode 1802 may be a laminate of the same embodiment, or may be a laminate of different embodiments.

Therefore, according to one embodiment of the electrostatic actuator of the present invention, it is possible to reduce the occurrence of hillocks in at least one of the movable electrode 1801 and the fixed electrode 1802, and the variation of the operating voltage due to the inaccurate actuator distance. It is possible to prevent the breakdown voltage from being lowered and the operation to be unstable.

That is, in the electrostatic actuator of this embodiment, the controllability of the distance between the actuators is improved, so
The variation in operating voltage of the element is reduced, and the operating voltage is stabilized.

Further, in the electrostatic actuator of this embodiment, since the distance between the actuators can be stably obtained, the regular breakdown voltage characteristic can be maintained and the breakdown voltage is improved even when an overload is applied.

(Application Example to Capacitor) Next, as an application example of the above-mentioned laminated body, a case of application to a capacitor will be described. FIG. 19 is a schematic diagram of an embodiment of a capacitor according to the present invention.

One embodiment of the capacitor according to the present invention is provided with electrodes 1901 and 1902, and the first to fifth embodiments of the above-mentioned laminated body are used for at least one of the electrodes.

In the capacitor of this embodiment, both of the two electrodes 1901 and 1902 may be a laminate of the same embodiment or may be a laminate of different embodiments.

Also in the capacitor, if hillocks are prevented in the counter electrode, it is possible to improve the capacitance control accuracy and electric characteristics such as charging property.

This is a more remarkable effect when the inter-electrode distance is accurately controlled like a variable capacitor.

As described above, by using the laminated body of the first embodiment to the laminated body of the fifth embodiment described above for the capacitor, the capacitance of the capacitor can be accurately controlled.

(Application to Various Devices) Next, the case where the embodiment of the laminated body is applied to various devices will be described.

(Application to Measuring Device) A case where an electrostatic relay as a switch using the above-described laminated body embodiment is applied to a measuring device will be described. The measuring device according to the present invention includes a semiconductor manufacturing device such as an IC tester.

Here, the internal structure of the measuring device using one embodiment of the electrostatic relay as the switch according to the present invention will be described with reference to FIG. FIG. 20 is a block diagram of an internal configuration of a measuring device using an embodiment of the electrostatic relay as the switch according to the present invention.

In the measuring device 2001 shown in FIG. 20, the electrostatic relay 2003 is connected in the middle of each signal line from the internal circuit 2002 to the object to be measured (not shown), and each electrostatic relay 2003 is connected. The measurement target can be switched by turning on and off.

As described above, in the electrostatic relay as the switch using the above-described laminated body embodiment, its characteristics can be improved by preventing the occurrence of hillocks.

Therefore, when the electrostatic relay using the above-mentioned laminated body embodiment is used in the measuring device, the measuring device itself is improved according to the improvement of the characteristics of the electrostatic relay using these laminated body embodiments. The characteristics can also be improved.

(Application to Radio Device) A case where an electrostatic relay as a switch using the above-described laminated body embodiment is applied to a radio device will be described.

As such a radio device, for example, a mobile phone or a PDA can be cited.

Here, the internal structure of a radio device using one embodiment of the electrostatic relay as the switch according to the present invention will be described with reference to FIG. FIG. 21 is a block diagram of an internal configuration of a wireless device using one embodiment of the electrostatic relay as the switch according to the present invention described above.

In this wireless device 2101, the electrostatic relay 21
03 is connected between the internal circuit 2102 and the antenna 2104. By turning on and off the electrostatic relay 2104, the internal circuit 2102 can switch between a state in which transmission and reception is possible via the antenna 2104 and a state in which transmission and reception is not possible.

As described above, the characteristics of the electrostatic relay using the above-described laminated body embodiment can be improved by preventing the occurrence of hillocks.

Therefore, when the electrostatic relay using the above-described laminated body embodiment is used in a radio device, the radio device itself is improved in accordance with the improvement of the characteristics of the electrostatic relay using these laminated body embodiments. The characteristics can also be improved.

[0291]

As described above, according to the present invention,
It is possible to provide a laminate having a small number of hillocks and a small hillock size.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of a laminate according to the present invention.

FIG. 2 is a table showing Vickers hardness and electric conductivity of materials used for the first embodiment of the laminate according to the present invention.

FIG. 3 is a schematic view of a surface state of a metal laminated body using the laminated body of the first embodiment.

FIG. 4 is a cross-sectional view of a second embodiment of the laminated body according to the present invention.

FIG. 5 is a cross-sectional view of a third embodiment of the laminated body according to the present invention.

FIG. 6 is a sectional view of a fourth embodiment of the laminate according to the present invention.

FIG. 7 is a cross-sectional view of a fifth embodiment of the laminate according to the present invention.

FIG. 8 is a perspective view of an embodiment of an electrostatic relay as a switch according to the present invention.

FIG. 9 is a cross-sectional view of a first embodiment of a contact using the laminated body according to the present invention.

FIG. 10 is a sectional view of a second embodiment of a contact using the laminate according to the present invention.

FIG. 11 is a manufacturing process diagram of the electrostatic relay shown in FIGS. 8 to 10;

FIG. 12 is a schematic view of the operation of the electrostatic relay shown in FIGS. 8 to 11.

FIG. 13 is a graph showing a relationship between electrostatic attraction and an inter-electrode distance, which is applied to the electrostatic relay shown in FIGS. 8 to 12.

FIG. 14 is a sectional view of an embodiment of a capacitance type sensor as a detection device according to the present invention.

FIG. 15 is a schematic view of an embodiment of a joint portion according to the present invention.

FIG. 16 is a schematic perspective view of a capacitance type sensor to which an embodiment of a joint section according to the present invention is applied.

FIG. 17 is a cross-sectional view of one embodiment of the wiring according to the present invention using the laminate according to the present invention.

FIG. 18 is a schematic view of an embodiment of the electrostatic actuator according to the present invention using the laminate according to the present invention.

FIG. 19 is a schematic view of an embodiment of a capacitor according to the present invention.

FIG. 20 is a block diagram of an internal configuration of a measuring device using an embodiment of an electrostatic relay as a switch according to the present invention.

FIG. 21 is a block diagram of an internal configuration of a wireless device using one embodiment of the electrostatic relay as the switch according to the present invention described above.

FIG. 22 is an exploded view of a conventional MMR.

FIG. 23 is a schematic diagram of a hillock generation mechanism according to the gas theory.

FIG. 24 is a schematic view of a mechanism of hillock generation according to the stress theory.

[Explanation of symbols]

101 First layer 102 Second layer 103 Third layer 104 substrate 301 glass substrate 303 Au layer 304 Hillock 306 First Au layer 307 First Ru layer 308 Second Au layer 401 First layer 402 Second layer 403 Third layer 404 substrate 501 First layer 502 Second layer 503 Third layer 504 Fourth layer 505 substrate 601 First layer 602 Second layer 603 Third layer 604 4th layer 605 substrate 701 First layer 702 Second layer 703 Third layer 704 Layer 4 705 5th layer 706 substrate 812 fixed electrode 813, 814 Fixed contact 820 movable substrate 825 movable electrode 901 First Au layer 902 First Ru layer 903 Second Au layer 904 Second Ru layer 905 Cr layer 906 substrate 1001 Au layer 1002 Ru layer 1003 Al layer 1004 substrate 1401 Semiconductor substrate 1402 Fixed board 1403 movable electrode 1404 Wiring groove 1405 Fixed electrode 1406 recess 1501 Silicon substrate 1502 glass substrate 1503 First joint 1504 Second joint 1505 First joint 1506 Second junction 1610 fixed board 1611 fixed electrode 1612 Connection electrode 1612a Interconnect pad 1620 semiconductor substrate 1623 wiring groove 1624 step 1631 Wire bonding pad for fixed electrode 1632 connection electrode 1632a Interconnect pad 1701 substrate 1702 wiring layer 1703 Insulator 1704 Second wiring layer 1705 second insulating layer 1706 Hillock 1707, 1708 wiring layer 1801 movable electrode 1802 Fixed electrode 1803 substrate 1901, 1902 electrodes 2001 Measuring device 2002 Internal circuit 2003 Electrostatic relay 2101 radio 2102 Internal circuit 2103 Electrostatic relay 2104 antenna 2210 Silicon substrate 2211 glass substrate 2212 fixed electrode 2213, 2214 Fixed contact 2216 Bonding pad 2217, 2218 signal line 2220 movable electrode 2221 Anka 2222 Return spring 2224 bump 2227 movable contact

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/3205 H01L 29/84 Z 29/84 21/88 R (72) Inventor Koji Sano Kyoto City, Kyoto Prefecture 2F055 AA40 BB20 CC02 DD05 EE25 FF43 FF49 GG12 4F100 AB01B AB01C AB01D AB10B AB10D AB16B AB16D AB20C AB24B AB24C AB24DAB40B AB40B40D AB25B ABB ABB BA04 BA14 GB41 JK12C JK13B 4M112 AA01 AA02 AA10 BA07 CA01 CA02 CA11 CA13 DA16 DA18 EA03 EA11 FA20 5F033 HH07 HH08 HH13 HH14 HH17 HH19 HH20 MM08 MM15 XX16

Claims (18)

[Claims] 1. A laminate comprising at least a third layer formed on a substrate, a second layer formed on the third layer, and a first layer formed on the second layer. And a hardness of the second layer higher than a hardness of the first layer. 2. The laminated body according to claim 1, wherein the laminated body is formed of a metal. 3. The laminate according to claim 1, which is manufactured in a semiconductor process. 4. The laminate according to claim 1, wherein the second layer has a Vickers hardness of 150 or more. 5. The second layer is Ru, W, Mo, Ir, O
The laminated body according to claim 1, wherein at least one of s, Ag, and Pd is a component. 6. The laminated body according to claim 1, wherein the first layer and the third layer are formed of the same material. 7. The first layer comprises Au, Ni, Ag, P
7. The laminated body according to claim 1, wherein at least one of d, Al, Pt, and Rh is a component. 8. An adhesion layer formed so as to contact the substrate, wherein the adhesion layer has better adhesion than a layer formed on the opposite side of the adhesion layer to the substrate. The laminated body according to any one of claims 1 to 7, which is characterized. 9. A diffusion preventive layer formed so as to come into contact with the adhesion layer or the substrate, wherein the diffusion preventive layer has a small diffusion coefficient with respect to the other layers, or the diffusion preventive layer from the other layers. The layered product according to any one of claims 1 to 8, which has a small diffusion coefficient to the layer. 10. A switch using the laminate according to any one of claims 1 to 9 as at least one electrical contact. 11. A detecting device in which a distance between opposed surfaces changes according to a physical quantity, and the physical quantity is detected based on a change in the distance, wherein at least one of the opposite surfaces has at least one of the facing surfaces. A detection device, wherein the laminate according to item 1 is used. 12. The detection device according to claim 11, wherein the detection device is an electrostatic capacitance type sensor that detects the physical quantity based on a change in electrostatic capacitance due to a change in the distance between the opposing surfaces. 13. A joint part, which is formed using the laminate according to any one of claims 1 to 9 for the purpose of joining to the other joint part. 14. A wiring characterized by using the laminate according to any one of claims 1 to 9. 15. An electrostatic actuator, wherein the laminated body according to any one of claims 1 to 9 is used for at least one of a movable electrode and a fixed electrode. 16. A capacitor, wherein at least one of the counter electrodes uses the laminate according to any one of claims 1 to 9. 17. A measuring device using the switch according to claim 10. 18. A wireless device using the switch according to claim 10.