CN110838541B - Magnetoresistive device and method of forming same - Google Patents

Abstract

The invention provides a magneto-resistive device and a forming method thereof. The magneto-resistive device includes a magneto-resistor, a protection layer, a first conductive structure, and a second conductive structure. The magnetoresistance is disposed on the substrate, and the protection layer is formed on part of the magnetoresistance. The first conductive structure is disposed on the protective layer structure, and includes a lower barrier layer and a metal layer disposed on the lower barrier layer. The second conductive structure is disposed on the substrate and partially covers the magnetoresistance, and the second conductive structure includes the lower barrier layer and the metal layer. In the present invention, a protection material layer is formed on the magnetoresistance material layer, and then the magnetoresistance material layer and the protection material layer are patterned together, and the protection layer is only formed on the magnetoresistance without covering other areas. Therefore, in the subsequent process, the protection layer will no longer be cracked from the edge of the magnetoresistive pattern, which avoids the problem of partial peeling of the edge of the magnetoresistive pattern, thereby improving the manufacturing yield of the magnetoresistive device.

Description

Magnetoresistive device and method of forming same

technical field

The present invention relates to magneto-resistive devices, and more particularly to conductive structures of magneto-resistive devices and methods of manufacturing the same.

Background technique

Magnetoresistive devices have been widely used in various electronic products, such as personal computers, mobile phones, and digital cameras, for example. The magneto-resistive device includes a magneto-resistor made of magneto-resistive material, and the alignment direction of the magnetic moments of the magneto-resistor will be changed by an external magnetic field, so that the resistance value of the magneto-resistor will change. Common magnetoresistances include anisotropic magnetoresistor (AMR), giant magnetoresistor (GMR), and tunneling magnetoresistor (TMR). For example, in anisotropic magnetoresistance (AMR), the arrangement direction of its magnetic moment is generally parallel to the length direction of the magnetoresistance; when the arrangement direction of the magnetic moment is parallel to the direction of the current flowing through the magnetoresistance, the magnetoresistance has the maximum resistance value ; When the alignment direction of the magnetic moments is perpendicular to the direction of the current flowing through the magnetoresistance, the magnetoresistance has the minimum resistance value.

An example of a magnetoresistive device including an anisotropic magnetoresistive AMR, its electrical connection is generally a wiring that forms a conductive structure on the AMR, and for applications used to sense the direction and magnitude of a magnetic field, a barbershop-like structure will be formed on the AMR. The BBP conductive structure of the signboard (BarBer Pole) pattern is ideally designed so that the direction of the current flowing through the AMR is between the BBP conductive structures and along the shortest distance between the BBP conductive structures. The general design is to make the length direction of the BBP conductive structure form an angle of 45 degrees with the length direction of the AMR, so that the resistance of the AMR responds optimally to changes in the external magnetic field.

At present, in the manufacturing process of the magnetoresistive device, there are still many challenges in the process of the conductive structure, especially to reduce the damage to the magnetoresistive element. Therefore, the method for forming the magnetoresistive device still needs to be further improved.

Contents of the invention

Some embodiments of the present invention provide a magneto-resistive device including a magneto-resistor disposed on a substrate, a protection layer, a first conductive structure, and a second conductive structure. The magnetoresistance is disposed on the substrate. The protection layer is disposed on the part of the magnetoresistance. The first conductive structure is disposed on the passivation layer and includes a lower barrier layer and a metal layer disposed on the lower barrier layer. The second conductive structure is disposed on the substrate and partially covers the protective layer, and includes a lower barrier layer and a metal layer disposed on the lower barrier layer.

Some embodiments of the present invention provide a method for forming a magnetoresistive device, the method comprising sequentially forming a magnetoresistive material layer and a protective material layer on a substrate, performing a first patterning process on the protective material layer and the magnetoresistive material layer, To form the protection layer and the magnetoresistance respectively, sequentially form a first barrier material layer and a metal material layer on the substrate to cover the protection layer and the magnetoresistance, and perform a second patterning on the metal material layer and the first barrier material layer process to respectively form the metal layer and the lower barrier layer of the first conductive structure on the passivation layer. During the second patterning process, the protective layer protects the underlying magnetoresistance. The method also includes performing a wet etching process on the protection layer to remove a portion of the protection layer not covered by the first conductive structure.

In the present invention, a protection material layer is formed on the magnetoresistance material layer, and then the magnetoresistance material layer and the protection material layer are patterned together, and the protection layer is only formed on the magnetoresistance without covering other areas. Therefore, in the subsequent process, the protective layer will no longer be cracked from the edge of the magnetoresistive pattern, which avoids the problem of partial peeling of the edge of the magnetoresistive pattern, thereby improving the manufacturing yield of the magnetoresistive device.

In order to make the features and advantages of the present invention more comprehensible, some embodiments are specifically cited below, together with the accompanying drawings, for a detailed description as follows.

Description of drawings

Embodiments of the present invention can be better understood by referring to the following detailed description and examples together with the accompanying drawings. For clarity of the drawings, various elements in the drawings may not be drawn to scale, wherein:

1A-1D are schematic cross-sectional views showing magnetoresistive devices in different process stages according to some examples.

2A and 2B are schematic cross-sectional views showing magnetoresistive devices in different process stages according to other examples.

3A-3I are schematic cross-sectional views showing magnetoresistive devices at different process stages according to some embodiments of the present invention.

Reference signs:

50A～device area;

50B～sensing area;

100, 200, 300～magnetic resistance device;

102, 302 ~ substrate;

104, 316'～reluctance;

106, 320～the first barrier material layer;

106', 320A, 320B～lower barrier layer;

108, 322～metal material layer;

108', 322A, 322B~metal layer;

110, 324～second barrier material layer;

110', 324A, 324B～upper barrier layer;

112, 112', 326, 326A, 326B～anti-reflection coating;

114, 327～patterned photoresist layer;

116～patterned conductive structure;

202～adhesive layer;

304～active components;

306～interlayer dielectric layer;

308～contact piece;

310～intermetallic dielectric layer;

312～metal wire;

314～lead hole;

316～magnetic resistance material layer;

318～protective material layer;

318', 318'A, 318'B～protective layer;

328A～the first conductive structure;

328B～second conductive structure;

329 ~ sunken;

330～passivation layer;

332～opening;

350～the first patterning process;

360～the second patterning process;

D1～depth;

G～Gate structure;

S ~ distance;

S/D ~ source/drain region.

Detailed ways

The following disclosure provides a number of examples or embodiments for implementing different elements of the provided magnetoresistive device. Specific examples of each element and its configuration are described below to simplify the description of the embodiments of the present invention. Of course, these are just examples, not intended to limit the embodiments of the present invention. For example, if the description mentions that a first element is formed on a second element, it may include an embodiment in which the first and second elements are in direct contact, or may include an additional element formed between the first and second elements , so that they are not in direct contact with the example. In addition, the embodiments of the present invention may repeat reference numerals and/or letters in different examples. This repetition is for brevity and clarity rather than to show the relationship between the various embodiments discussed.

Some variations of the embodiment are described below. In the different drawings and described embodiments, like reference numerals are used to designate like elements. It is understood that additional steps may be provided before, during, and after the method, and that some recited steps may be substituted or deleted in other embodiments of the method.

1A-1D are schematic cross-sectional views showing the magnetoresistive device 100 shown in FIG. 1D in different process stages according to some examples. Please refer to FIG. 1D , the magnetoresistive device 100 includes a substrate 102 , a magnetoresistor 104 , and a patterned conductive structure 116 . In this example, the substrate 102 may include an active device (not shown) disposed therein, and an intermetal dielectric layer (not shown) is formed on the upper portion of the substrate 102 over the active device. The active device is electrically connected to the conductive structure 116 and the magnetoresistor 104 via the interconnect structure. The magnetoresistor 104 is disposed on the IMD layer of the substrate 102 . The patterned conductive structure 116 is disposed on the part of the magnetoresistor 104 to change the direction of the current flowing through the magnetoresistor between the patterned conductive structures 116, so that the resistance value of the magnetoresistor 104 responds linearly to the change of the applied magnetic field. . The patterned conductive structure 116 includes a lower barrier layer 106 ′, a metal layer 108 ′, an upper barrier layer 110 ′, and an anti-reflection coating 112 ′ stacked on the magnetoresistor 104 in sequence. The method for forming the magnetoresistive device 100 of FIG. 1D will be described below.

Referring to FIG. 1A , a substrate 102 is provided, and a magnetoresistive material layer is formed on the substrate 102 . In this example, the magnetoresistive material layer may be made of nickel iron (NiFe), cobalt iron (CoFe), cobalt iron boron (CoFeB), platinum manganese (PtMn), ruthenium (Ru), iridium manganese (IrMn), copper (cu), tantalum (Ta) and other materials stacked structure.

至约

的范围内。Next, a patterning process is performed on the magnetoresistive material layer to form a patterned magnetoresistor 104 , such as an anisotropic magnetoresistance (AMR) or a giant magnetoresistance (GMR). In this example, the patterning process includes forming a patterned photoresist layer (not shown) over the magnetoresistive material layer, performing a dry etching process on the magnetoresistive material layer, and removing the magnetoresistive material layer not masked by the patterning. The portion covered by the mask layer is then removed from the patterned photoresist layer. In order to completely remove the portion of the magnetoresistive material layer not covered by the patterned photoresist layer, a general dry etching process will over-etch the intermetal dielectric layer of the substrate 102 to form a height difference of depth D1, for example, about 500 angstroms.

to about

In the range.

Referring to FIG. 1B , a first barrier material layer 106 , a metal material layer 108 , a second barrier material layer 110 , and an anti-reflective coating 112 are sequentially formed on the substrate 102 to cover the magnetoresistor 104 . In this example. The material of the first barrier material layer 106 may comprise titanium tungsten (TiW), titanium nitride (TiN) or titanium (Ti), the material of the metal material layer 108 comprises aluminum copper (AlCu) alloy, and the material of the second barrier material layer 110 The material includes titanium nitride (TiN).

Referring to FIG. 1B , a patterning process is performed on the antireflection coating 112 , the second barrier material layer 110 , and the metal material layer 108 . The step of the patterning process includes forming a patterned photoresist layer 114 over the anti-reflective coating 112 .

The step of the patterning process also includes the anti-reflection coating 112, the second barrier material layer 110, and the metal material layer 108 performing a dry etching process together to remove the anti-reflection coating 112, the second barrier material layer 110, and the metal material Portions of layer 108 not covered by patterned photoresist layer 114 . In the etching process, the corrosion rate of the first barrier material layer 106 is lower than the corrosion rate of the metal material layer 108, so the first barrier material layer 106 is used as a corrosion stop layer for corroding the metal material layer 108 to protect the magnetoresistance 104 below from Damaged by Corrosion. Referring to FIG. 1C , after the dry etching process, a patterned anti-reflective coating 112 ′, a patterned upper barrier layer 110 ′, and a patterned metal layer 108 ′ are formed. The patterning process further includes removing the patterned photoresist layer 114 through an ashing process.

Next, in order to avoid damage to the magnetoresistor 104, a wet etching process is used to remove the part of the first barrier material layer 106 not covered by the anti-reflection coating 112', the upper barrier layer 110' and the metal layer 108' to form a lower barrier The conductive structure 116 is completed after the layer 106', please refer to FIG. 1D.

It is worth noting that the general dry etching process of the magnetoresistor 104 will over-etch the intermetallic dielectric layer of the substrate 102 to form a height difference of the depth D1, and the adhesion between the first barrier material layer 106 and the magnetoresistor 104 The force is greater than the adhesion force between the magnetoresistive 104 and the IMD layer of the substrate 102 . Therefore, in the ashing process of the patterned photoresist layer 114, the deformation stress of the first barrier material layer 106 due to high temperature tends to be partially cracked from the height difference of the pattern edge of the magnetoresistor 104 to release the stress. , causing the edge of the pattern of the magnetoresistor 104 to be stuck by the partially cracked first barrier material layer 106 and separated from the intermetallic dielectric layer of the substrate 102, causing the subsequent wet etching process to remove part of the first barrier material layer 106, local peeling occurs at the edge of the pattern of the magnetoresistor 104, for example, in the region A indicated in FIG. 1D. Therefore, the manufacturing yield of the magnetoresistive device 100 is lowered and the reliability is damaged.

2A and FIG. 2B are schematic cross-sectional views showing the magnetoresistive device 200 shown in FIG. 2B at different process stages according to other examples, wherein the components that are the same as those in the aforementioned examples of FIGS. 1A-1D use the same reference numerals and omit them. illustrate. The difference between the embodiment shown in FIG. 2A and FIG. 2B and the aforementioned examples in FIG. 1A-FIG. 1D is that the magnetoresistive device 200 in FIG. 2A and FIG. There is an adhesive layer 202 containing tantalum (Ta). The magnetoresistance 104 of the example of FIG. 2A and FIG. 2B is to pad the adhesive layer 202 between the intermetal dielectric layer of the substrate 102 under the magnetoresistance material, so that the magnetoresistance 104 and the intermetal dielectric layer of the substrate 102 are increased. The adhesive force between them can solve the above-mentioned peeling problem of the magnetoresistor 104 .

Referring to FIG. 2A , an adhesive material layer, such as tantalum (Ta), is formed on the intermetallic dielectric layer of the substrate 102 , and then a magnetoresistive material layer is formed on the adhesive material layer. A patterning process is performed on the magnetoresistive material layer and the adhesive material layer to form the patterned magnetoresistor 104 and the patterned adhesive layer 202 . Next, the same or similar process steps as those described above in FIGS. 1A-1D are performed to form the magnetoresistive device 200 shown in FIG. 2B .

Since the adhesive layer 202 will enhance the adhesion between the magnetoresistor 104 and the intermetal dielectric layer of the substrate 102, the adhesive layer 202 can prevent the first The barrier material layer 106 is split from the pattern edge elevation difference of the magnetoresistor 104 in a localized manner. Therefore, when the subsequent wet etching process removes part of the first barrier material layer 106 , local peeling of the pattern edge of the magnetoresistor 104 will not occur again. For example, in the region A indicated in FIG. 2B , this avoids the local peeling problem of the magnetoresistor 104 in the region A described in FIG. 1D .

In this example, for example, tantalum is used as the material of the adhesive layer. In order to prevent the tantalum atoms of the adhesive layer 202 from diffusing into the magnetoresistor 104, the magnetoresistance ratio (MR%) of the magnetoresistor 104 is reduced. The process temperature after the resistor 104 is limited to below 300°C. For example, in the example of FIG. 1A-FIG. 1D, the chemical vapor deposition (chemical vapor deposition, CVD) process temperature of the anti-reflective coating 112 is formed at a temperature in the range of about 300° C. to about 400° C., but in FIGS. In the example of FIG. 2B , the chemical vapor deposition (CVD) process for forming the anti-reflective coating 112 is performed at a temperature of about 250° C. to about 300° C. Lower temperature chemical vapor deposition (CVD) has a lower deposition rate and poorer thickness uniformity, and causes more undesirable particle appearance, which reduces the production efficiency and production yield of the magnetoresistive device 200 . In addition, limiting the process temperature to be lower than 300° C. will result in that the magnetoresistor 104 cannot be subsequently annealed at a high temperature to increase the magnetoresistance ratio (MR%).

3A-3I are schematic cross-sectional views showing the magnetoresistive device 300 shown in FIG. 3I in different process stages according to some embodiments of the present invention. In the case of not using an adhesive material layer between the magnetoresistive material and the intermetallic dielectric layer, the embodiments of FIGS. 3A-3I form a protective material layer on the magnetoresistive material layer before patterning the magnetoresistive material layer. On top of that, the protective material layer and the magnetoresistive material layer are patterned together, which avoids the deformation stress problem of the first barrier material layer caused by the height difference caused by the dry corrosion of the magnetoresistive material layer, so as to solve the problem of Fig. 1A-Fig. 1D The peeling problem of the magnetoresistance.

Referring to FIG. 3A , a substrate 302 is provided. Substrate 302 may be any substrate on which a magnetoresistive device may be formed. In some embodiments, the substrate 302 may be a silicon substrate, a silicon germanium (SiGe) substrate, a bulk semiconductor substrate, a compound semiconductor substrate, or a silicon on insulator substrate. , SOI) substrates or similar substrates.

In some embodiments, substrate 302 includes device region 50A and sense region 50B. Active device 304 is formed in device region 50A of substrate 302 . In one embodiment, the active element 304 may be a triode, a diode or similar active elements. For example, the active device 304 is a field effect transistor (FET), which includes a gate structure G and a source/drain region S/D.

Next, an interconnection structure is formed on the substrate 302 . The interconnect structure includes an ILD layer 306 , a contact 308 , an IMD layer 310 , metal lines 312 and vias 314 .

An interlayer dielectric layer 306 is formed on the substrate 302 and covers the active device 304 . In some embodiments, the material of the interlayer dielectric layer 306 may include or be phosphosilicate glass (phosphosilicate glass, PSG), borophosphosilicate glass (borophosphosilicate glass, BPSG), undoped silicate Glass (undoped silicate glass, USG), fluorinated silicate glass (fluorinated silicate glass, FSG), similar materials, multiple layers of the foregoing or combinations of the foregoing, and may be deposited by chemical vapor deposition (chemical vapor deposition, CVD), e.g. Plasma-enhanced chemical vapor deposition (plasma-enhanced CVD, PECVD) to form an interlayer dielectric layer 306 .

The contact 308 passes through the interlayer dielectric layer 306 to electrically connect the active device 304 . Although FIG. 3A shows that the contact 308 is connected to the source/drain region S/D of the active device 304 , in other embodiments, the contact 308 may be connected to the gate structure G of the active device 304 . In some embodiments, the material of the contact 308 may include or be a conductive material such as; tungsten (W), nickel (Ni), titanium (Ti), tantalum (Ta), aluminum (Al), copper (Cu), Titanium nitride (TiN), tantalum nitride (TaN), similar materials, multiple layers of the foregoing, or combinations of the foregoing, and the contact 308 may be formed by an etching process and a deposition process. The deposition process can include chemical vapor deposition (CVD), atomic layer deposition (atomic layer deposition, ALD), or physical vapor deposition (physical vapor deposition, PVD). Physical vapor deposition (PVD) can be sputtering or pulsed laser deposition (PLD).

An IMD layer 310 is formed on the ILD layer 306 . In some embodiments, the material of the intermetal dielectric layer 310 may include or be silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon carbonitride, silicon oxycarbide, phosphosilicate glass (PSG), Borophosphosilicate glass (BPSG), undoped silicate glass (USG), fluorinated silicate glass (FSG), similar materials, multiple layers of the foregoing, or combinations of the foregoing, and may be deposited by chemical vapor (CVD), such as plasma enhanced chemical vapor deposition (PECVD), to form the IMD layer 310 .

Metal lines 312 and lead holes 314 are formed in the IMD layer 310 and electrically connect the contacts 308 . Although FIG. 3A shows a layer of intermetal dielectric layer 310 with metal lines 312 and lead holes 314 therein, in other embodiments, multiple layers of intermetal dielectric layer 310 and the intermetal dielectric layer located in each layer may be formed. Metal lines 312 and lead holes 314 in the electrical layer 310 . In some embodiments, the material of the metal line 312 and the lead hole 314 may include or be a conductive material, such as; tungsten (W), nickel (Ni), titanium (Ti), tantalum (Ta), aluminum (Al), copper (Cu), titanium nitride (TiN), tantalum nitride (TaN), similar materials, multiple layers of the foregoing, or combinations of the foregoing, and metal lines can be formed by a single damascene or dual damascene process 312 and lead hole 314.

Continuing to refer to FIG. 3A , a magnetoresistive material layer 316 is formed over the IMD layer 310 . In some embodiments, there is no adhesion layer containing tantalum (Ta) between the IMD layer 310 and the magnetoresistive material layer 316 . In some embodiments, the magnetoresistive material layer 316 may comprise or be nickel iron (NiFe), cobalt iron (CoFe), cobalt iron boron (CoFeB), copper (Cu), platinum manganese (PtMn), iridium manganese (IrMn) , ruthenium (Ru) and other similar materials, the aforementioned multilayers, combinations of the aforementioned, or other stacked structures suitable for forming anisotropic magnetoresistance (AMR) or giant magnetoresistance (GMR), and can be deposited by chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), similar methods, or a combination of the foregoing, are formed on the IMD layer 310 .

Referring to FIG. 3B , a protective material layer 318 is formed on the magnetoresistive material layer 316 . In some embodiments, the protective material layer 318 may have a thickness in the range of about 300A to about 1500A. In some embodiments, the protective material layer 318 may include or be titanium tungsten (TiW), titanium (Ti), titanium nitride (TiN), similar materials, or combinations thereof, and may be formed by physical vapor deposition (PVD), atomic Layer deposition (ALD), similar methods, or a combination of the foregoing, forms protective material layer 318 . Physical vapor deposition (PVD) can be sputtering or pulsed laser deposition (PLD). In one embodiment, the protective material layer 318 includes titanium tungsten (TiW), wherein the weight ratio of titanium and tungsten is about 1:9.

Next, a first patterning process 350 is performed on the protective material layer 318 and the magnetoresistive material layer 316 . Referring to FIG. 3C, after the first patterning process 350, the protective material layer 318 and the magnetoresistive material layer 316 respectively form a patterned protective layer 318' and a patterned magnetoresistive layer 316' located in the sensing region 50B of the substrate 302. .

In some embodiments, the step of the first patterning process 350 includes forming a photoresist patterned mask layer (not shown), such as a patterned photoresist layer or pattern, over the protective material layer 318 shown in FIG. 3B harden the mask layer, perform a dry etching process on the protective material layer 318 and the magnetoresistive material layer 316 together, remove the protective material layer 318 and the magnetoresistive material layer 316 not covered by the patterned mask layer, to form a protective layer 318 ′ and the magnetoresistor 316 ′, and then remove the patterned mask layer on the passivation layer 318 ′, such as by an ashing process or a stripping process. In some embodiments, where the patterned mask layer is a patterned photoresist layer, the dry etching process and the ashing process may be performed in-situ in an etcher. In some embodiments, the dry etching process of the first patterning process 350 may be reactive ion etch (reactive ion etch, RIE), electron cyclotron resonance (electron cyclotron resonance, ERC) etching, inductively coupled plasma (inductively -coupled plasma (ICP) etching, neutron beam etching (neutral beam etch, NBE), ion beam etching (ion bean etch, IBE) similar to dry etching processes or a combination of the aforementioned reactive ion etching (RIE).

In some embodiments, in order to completely remove the protective material layer 318 and the magnetoresistive material layer 316 not covered by the patterned mask layer, the dry etching process will or over-etch the intermetal dielectric layer 310 to a depth D1, such as Figure 3C.

Referring to FIG. 3D , a first barrier material layer 320 is formed on the IMD layer 310 to cover the passivation layer 318 ′ and the magnetoresistor 316 ′. The first barrier layer 320 is used to prevent tungsten (W) atoms from the material of the lead hole 314 from diffusing into the subsequently formed metal material layer 322 (eg, aluminum copper (AlCu) alloy). The thickness of the first barrier material layer 320 may range from about 250A to about 750A. In some embodiments, the first barrier material layer 320 may comprise or be titanium nitride (TiN), titanium (Ti), tantalum nitride (TiN), tantalum (Ta), similar materials, or combinations thereof, and may be passed through The first barrier material layer 320 is formed by physical vapor deposition (PVD), atomic layer deposition (ALD), similar methods or a combination thereof. Physical vapor deposition (PVD) can be sputtering or pulsed laser deposition (PLD).

Next, a metal material layer 322 is formed on the first barrier material layer 320 . In some embodiments, the thickness of the metallic material layer 322 may range from about 3000A to about 8000A. In some embodiments, the metal material layer 322 may include or be aluminum copper (AlCu), aluminum silicon copper (AlSiCu) or similar materials, and may be formed by physical vapor deposition (PVD), atomic layer deposition (ALD), electroplating (electroplating) ), a similar method or a combination of the foregoing to form the metal material 322. Physical vapor deposition (PVD) can be sputtering or pulsed laser deposition (PLD).

Next, a second barrier material layer 324 is formed on the metal material layer 322 . The second barrier material layer 324 is used to prevent the metal material layer 322 from being oxidized. In some embodiments, the thickness of the second barrier material layer 324 may range from about 500A to about 1000A. In some embodiments, the second barrier material layer 324 may comprise or be titanium nitride (TiN), titanium (Ti), tantalum nitride (TiN), tantalum (Ta), similar materials, or combinations thereof, and may be formed by The second barrier material layer 324 is formed by chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), similar methods or a combination thereof. Physical vapor deposition (PVD) can be sputtering or pulsed laser deposition (PLD). The material of the second barrier material layer 324 may be the same as or different from that of the first barrier material layer 320 .

Next, an anti-reflective coating 326 is formed over the second barrier material layer 324 . In some embodiments, the thickness of the antireflective coating 326 may range from about 250A to about 500A. In some embodiments, the material of the anti-reflective coating 326 may include or be silicon oxide (SiO ₂ ), silicon nitride (SiN), silicon oxynitride (SiON), silicon carbide (SiC), silicon carbonitride (SiCN ), silicon oxycarbide (SiOC), similar materials, or combinations thereof, and the antireflective coating 326 may be formed by chemical vapor deposition (CVD), such as plasma enhanced chemical vapor deposition (PECVD).

In the embodiment of FIG. 3D, since no adhesive material layer, such as tantalum (Ta), is used, the chemical vapor deposition (CVD) to form the anti-reflective coating 326 may be performed at a high temperature, such as a temperature of about 300° C. to about 400° C. within range. Using chemical vapor deposition (CVD) performed at a higher temperature to form the anti-reflective coating 326 not only results in a higher deposition rate and better thickness uniformity, but also has less undesirable particle performance, thereby improving magnetic properties. The production efficiency and production yield of the resistance device.

Next, a second patterning process 360 is performed on the antireflection coating 326 , the second barrier material layer 324 , the metal material layer 322 and the first barrier material layer 320 to form the first conductive structure 328A and the first conductive structure 328B. Hereinafter, the second patterning process 360 will be described in detail.

Referring to FIG. 3E , the step of the second patterning process 360 includes forming a patterned photoresist layer 327 on the anti-reflection coating 326 .

The step of the second patterning process 360 also includes performing a dry etching process together with the antireflection coating 326, the second barrier material layer 324, the metal material layer 322 and the first barrier material layer 320 to remove the unpatterned photoresist Layer 327 covers antireflective coating 326 , second barrier material layer 324 , metallic material layer 322 and first barrier material layer 320 . In some embodiments, the dry etching process of the second patterning process 360 may be reactive ion etching (RIE), electron cyclotron resonance (ERC) etching, inductively coupled plasma (ICP) etching, neutron beam etching ( NBE), a similar dry etching process, or the aforementioned resistance. During the dry etching process of the second patterning process 360, the protection layer 318' functions to protect the underlying magnetoresistor 316' from being damaged by the dry etching.

In some embodiments, for example, the protective layer 318' is titanium tungsten (TiW), the first and second barrier material layers 320, 324 are titanium nitride (TiN), the metal material layer 322 is aluminum copper (AlCu) alloy, anti- Reflective coating 326 is silicon nitride. Because the corrosion rate of titanium tungsten (TiW) of the protection layer 318' is lower than the corrosion rate of titanium nitride (TiN) of the first barrier material layer 320, the titanium tungsten (TiW) of the protection layer 318' has an effect on the corrosion rate of the first barrier material layer 320 Titanium nitride (TiN) has a high etch selectivity in the range of about 4 to 10 times. Therefore, the etching process of the second patterning process 360 generally adopts the endpoint mode (endpoint mode) to detect the completion of the corrosion of the metal material layer 322, and then adopts the time mode (time mode) to perform the etching of the first barrier material layer 320, using the protective layer The high corrosion selectivity of titanium tungsten (TiW) of 318 ′ to titanium nitride (TiN) of the first barrier material layer 320 protects the underlying magnetoresistor 316 ′, preventing the magnetoresistor 316 ′ from being corroded.

In some embodiments, for example, the protection layer 318' is titanium nitride (TiN), the first and second barrier material layers 320, 324 are titanium nitride (TiN), the metal material layer 322 is aluminum copper (AlCu) alloy, Anti-reflective coating 326 is silicon nitride. Because the corrosion rate of the protective layer 318' is the same as that of the first barrier material layer 320, in this embodiment, the titanium nitride (TiN) of the protective layer 318' can be made thicker, for example, as the first barrier material layer 320. The thickness of the material layer is in the range of 2 to 3 times, so as to ensure that after the first barrier material layer 320 is corroded completely, the protective layer 318 ′ still has enough thickness to avoid corrosion damage to the magnetoresistor 316 ′.

Please refer to FIG. 3F, after the dry etching process of the second patterning process 360, a first conductive structure 328A is formed in the sensing region 50B, the first conductive structure 328A includes a patterned anti-reflection coating 326A, a patterned upper barrier layer 324A, the patterned metal layer 322A and the patterned lower barrier layer 320' are on a portion of the passivation layer 318'.

In addition, after the dry etching process of the second patterning process 360, a second conductive structure 328B is formed in the device region 50A, and the second conductive structure 328B includes a patterned anti-reflective coating 326B, a patterned upper barrier layer 324B, a patterned The metal layer 322B and the patterned lower barrier layer 320B are on the IMD layer 310 . The lower barrier layer 320B is in contact with and electrically connected to the lead hole 314 in the intermetal dielectric layer 310 . Moreover, the second conductive structure 328B extends to the sensing region 50B to partially cover the protective layer 318 ′ and the magnetoresistor 316 ′, so as to form an electrical connection with the magnetoresistor 316 ′.

After the dry etching process of the second patterning process 360 , the protective layer 318 ′ still completely covers the upper surface of the magnetoresistor 316 ′, as shown in FIG. 3F .

The step of the second patterning process 360 also includes removing the patterned photoresist layer 327 , such as by an ashing process, as shown in FIG. 3G . In some embodiments, the etching process and the ashing process of the second patterning process 360 may be performed in-situ in a dry etching tool.

It should be noted that after the etching process of the first patterning process 350, the stress of the protection layer 318' on the magnetoresistor 316' has been released, and it is only formed on the magnetoresistor 316' without covering other areas (such as , the upper surface of the intermetal dielectric layer 310). Moreover, after the first conductive structure 328A and the second conductive structure 328B are formed through the second patterning process 360 , the stress of the conductive structures on the protection layer 318 ′ has been released. Therefore, the problem of partial peeling of the pattern edge of the magnetoresistor 316 ′ caused by the protection layer 318 ′ being cracked from the pattern edge of the magnetoresistor 316 ′ as described in the example of FIGS. 1A-1D does not occur.

After the second patterning process 360, the portion of the protective layer 318' on the magnetoresistor 316' that is not covered by the first conductive structure 328A and the second conductive structure 328B is removed, leaving the protective layers 318'A and 318'B ( Also referred to as remaining portions 318'A and 318'B), please refer to FIG. 3H. In some embodiments, this removal may be performed by a wet etch process.

In some embodiments, for example, titanium tungsten (TiW) or titanium nitride (TiN) is used as the protective layer 318 ′, and the etchant of the wet etching process can use a solution containing hydrogen peroxide (H ₂ O ₂ ), which can Avoid damaging the reluctance 316'. The protection layer 318' is subjected to a wet etching process to form the protection layers 318'A and 318'B, and since the wet etching process is isotropic, a depression with a lateral side etching retraction distance S will be formed. 319.

Referring to FIG. 3I , a passivation layer 330 is formed over the intermetal dielectric layer 310 . A passivation layer 330 covers the first and second patterned conductive structures 328A and 328B and the magnetoresistor 316'. In some embodiments, the material of the passivation layer 330 may include or be silicon oxide, silicon nitride, silicon oxynitride, similar materials, or combinations thereof, and may be deposited by chemical vapor deposition (CVD), or, for example, plasma-enhanced chemical vapor deposition. deposition (PECVD) to form passivation layer 330 . Afterwards, the passivation layer 330 is etched to form an opening 332 on the second patterned conductive structure 328B, and the fabrication of the magnetoresistive device 300 is completed.

In the embodiment of FIGS. 3A-3I , there is no adhesion layer of tantalum (Ta) between the magnetoresistor 316 ′ and the IMD layer 310 . Accordingly, chemical vapor deposition (CVD) to form the passivation layer 330 may be performed at a higher temperature, for example, within a temperature range of about 400°C to about 450°C. The use of higher temperature chemical vapor deposition to form the passivation layer 330 not only results in a higher deposition rate and better thickness uniformity, but also has fewer undesirable particles, thereby improving the performance of the magnetoresistive device. Production efficiency and production yield.

Moreover, after the passivation layer opening 332 is completed, high temperature annealing may be performed on the magnetoresistive device 300, for example, the annealing temperature is in the range of 350° C. Resistance ratio (MR%) and reduced sheet resistance (Rsq).

In the embodiment of the present invention, the magnetoresistive device 300 includes an intermetallic dielectric layer 310 disposed on the substrate 302 , a magnetoresistor 316 ′, a protection layer 318 ′A, and a first conductive structure 328A. The magnetoresistor 316 ′ is disposed in the sensing region 50B of the substrate 302 and above the IMD layer 310 . A passivation layer 318'A is formed over a portion of the magnetoresistor 316'. The first conductive structure 328A is disposed on the passivation layer 318'A. The first conductive structure 328A is used to change the direction of the current flowing through the magnetic resistance 316 ′ between the adjacent first conductive structures 328A, so that the magnetic resistance value responds linearly to the change of the applied magnetic field. Although it is shown in FIG. 3I that two first conductive structures 328A are formed on the magnetoresistor 316 ′, the number of the first conductive structures 328A can be adjusted based on design requirements, and is not limited to the illustrated embodiment.

In some embodiments, the first patterned conductive structure 328A includes a lower barrier layer 320A, a metal layer 322A, an upper barrier layer 324A, and an anti-reflection coating 326A stacked on the passivation layer 318 ′A in sequence.

In some embodiments, the magnetoresistive device 300 further includes a second conductive structure 328B laterally spaced from the first conductive structure 328A and disposed in the device region 50A of the substrate 302 . The second conductive structure 328B further extends to the sensing region 50B to cover the protective layer 318 ′B and the edge of the magnetoresistor 316 ′, and forms an electrical connection with the magnetoresistor 316 ′. The second patterned conductive structure 328B includes a lower barrier layer 320B, a metal layer 322B, an upper barrier layer 324B and an anti-reflection coating 326B stacked on the IMD layer 310 in sequence. Moreover, the lead hole 314 in the IMD layer 310 contacts and is electrically connected to the lower barrier layer 320B of the second conductive structure 328B.

In some embodiments, the material of the lead hole 314 is tungsten (W), and the material of the lower barrier layer 320B is tantalum nitride (TiN). Compared with other materials such as titanium tungsten (TiW), tantalum nitride (TiN) has a better blocking ability for tungsten atoms. Therefore, the tantalum nitride (TiN) lower barrier layer 320B can preferably prevent the tungsten atoms from diffusing to the upper metal layer 322B, so as to improve the reliability of the magnetoresistive device 300 .

In summary, the embodiments of the present invention utilize the formation of a protective material layer on the magnetoresistive material layer, and then pattern the magnetoresistive material layer and the protective material layer together. The protective layer is only formed on the magnetoresistive material layer and does not cover other areas (such as , the surface of the intermetal dielectric layer 310). Therefore, in the subsequent process, the protective layer will no longer be cracked from the edge of the magnetoresistive pattern, which avoids the problem of local peeling (peel) at the edge of the magnetoresistive pattern, thereby improving the manufacturing yield of the magnetoresistive device.

Furthermore, in some embodiments, the process temperature is not limited below 300° C. due to the absence of a tantalum-containing adhesion layer between the magnetoresistor and the IMD layer. Chemical vapor deposition performed at a higher temperature not only results in a higher film deposition rate and better thickness uniformity, but also has fewer undesirable particles, thereby improving the production efficiency and production yield of the magnetoresistive device. Furthermore, after forming the magnetoresistive device, high-temperature annealing can be performed on the magnetoresistive device to further improve the characteristics of the magnetoresistance.

Several embodiments are summarized above, so that those skilled in the art to which the present invention belongs can better understand the viewpoints of the embodiments of the present invention. Those skilled in the technical field of the present invention should understand that they can design or modify other processes and structures based on the embodiments of the present invention, so as to achieve the same purpose and/or advantages as the embodiments introduced here. Those skilled in the technical field of the present invention should also understand that such equivalent processes and structures do not depart from the spirit and scope of the present invention, and they can make various modifications without departing from the spirit and scope of the present invention. Various changes, substitutions and substitutions.

Claims (17)

1. A magnetic resistance device, characterized in that, comprising: a magnetoresistor disposed on a substrate; a protective layer formed over a portion of the magnetoresistance; and A first conductive structure, disposed on the protective layer, the first conductive structure includes: a first portion of the lower barrier layer and a first portion of a metal layer disposed on the first portion of the lower barrier layer; and A second conductive structure is disposed on the substrate and partially covers the magnetoresistor, the second conductive structure includes: a second portion of the lower barrier layer and a second portion of the metal layer disposed on the second portion of the lower barrier layer; and An intermetallic dielectric layer disposed on the substrate, wherein the magnetic resistance and the second conductive structure are disposed on the intermetallic dielectric layer, and a lead hole in the intermetallic dielectric layer is connected to the first The two conductive structures are electrically connected. 2 . The magnetoresistive device according to claim 1 , wherein the protection layer is made of titanium tungsten (TiW), titanium Ti or titanium nitride TiN. 3. The magnetoresistive device as claimed in claim 1, wherein the material of the lower barrier layer comprises titanium nitride TiN, titanium Ti, tantalum nitride TaN or tantalum Ta. 4. The magnetoresistive device according to claim 1, wherein the protection layer is further disposed between the second conductive structure and the magnetoresistor. 5. The magnetoresistive device according to claim 1, wherein the first conductive structure further comprises: An upper barrier layer and an anti-reflection coating are sequentially stacked on the metal layer of the first conductive structure. 6. The magnetoresistive device according to claim 1, wherein the second conductive structure further comprises: An upper barrier layer and an anti-reflection coating are sequentially stacked on the metal layer of the second conductive structure. 7. A method for forming a magnetoresistive device, comprising: sequentially forming a magnetoresistive material layer and a protective material layer on a substrate; performing a first patterning process on the protective material layer and the magnetoresistive material layer to respectively form a protective layer and a magnetoresistance; sequentially forming a first barrier material layer and a metal material layer on the substrate to cover the protection layer and the magnetoresistance; performing a second patterning process on the metal material layer and the first barrier material layer to respectively form a metal layer and a lower barrier layer of a first conductive structure on the protection layer, wherein the second pattern During the oxidation process, the protective layer protects the underlying magnetoresistance; and A wet etching process is performed on the passivation layer to remove the portion of the passivation layer not covered by the first conductive structure. 8 . The method for forming a magnetoresistive device according to claim 7 , wherein the first patterning process comprises performing a dry etching on the protective material layer and the magnetoresistive material layer. 9. The method for forming a magnetoresistive device according to claim 7, wherein the protective material layer comprises titanium tungsten TiW, titanium Ti or titanium nitride TiN. 10 . The method for forming a magnetoresistive device according to claim 7 , wherein the etchant used in the wet etching process is a solution containing hydrogen peroxide H ₂ O ₂ . 11. The method for forming a magnetoresistive device according to claim 7, wherein the first barrier material layer comprises titanium nitride TiN, titanium Ti, tantalum nitride TaN or tantalum Ta. 12 . The method for forming a magnetoresistive device according to claim 7 , wherein the metal material layer comprises aluminum-copper-AlCu alloy, aluminum-Al or aluminum-silicon-copper-AlCuSi alloy. 13. The method for forming a magnetoresistive device according to claim 7, further comprising: sequentially forming a second barrier material layer and an anti-reflective coating layer on the metal material layer; Wherein the second barrier material layer comprises titanium nitride TiN, titanium Ti, tantalum nitride TaN or tantalum Ta; Wherein the anti-reflection coating comprises silicon nitride SiN or silicon oxynitride SiON; Wherein the second patterning process is further performed on the second barrier material layer and the anti-reflection coating to respectively form an upper barrier layer and an anti-reflection coating of the first conductive structure. 14. The method for forming a magnetoresistive device according to claim 7, further comprising: Before forming the magnetoresistance material layer, an intermetal dielectric layer is formed on the substrate, wherein the magnetoresistance material layer is formed on the intermetal dielectric layer. 15. The method for forming a magnetoresistive device according to claim 14, wherein after the second patterning process, the metal material layer and the first barrier material layer are further respectively formed on the intermetal dielectric layer the metal layer and the lower barrier layer of a second conductive structure above; Wherein the second conductive structure partially covers the protection layer. 16 . The method for forming a magnetoresistive device as claimed in claim 15 , wherein after the wet etching process, the portion of the protection layer covered by the second conductive structure remains unremoved. 17. The method for forming a magnetoresistive device as claimed in claim 15, wherein a lead hole in the intermetal dielectric layer is electrically connected to the lower barrier layer of the second conductive structure.

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