CN102337089B - Tape for wafer processing and semiconductor processing method using same - Google Patents

Abstract

The invention provides a wafer processing adhesive tape capable of fully inhibiting re-bonding of semiconductor chips during pickup and a method for processing a semiconductor therewith. The wafer processing tape is a cutting chip sticking tape 10 of a wafer-processing-used adhesive tape of a thermosetting cement layer 13 comprising a compound provided with epoxy radical and laminated on an adhesive layer 12b of a cutting tape 12 of a bonding tape formed by a supporting base material 12a and an adhesive layer 12b, the wafer-processing-used adhesive tape is characterized in that: the supporting base material 12a is formed by ionomer resin formed by crosslinking of metal ions used for ethylene-(methyl) acrylic acid binary copolymers or ethylene- (methyl) acrylic acid- (methyl) acrylic acid alkyl ester ternary copolymers; weight part fraction of the (methyl) acrylic acid component in the copolymer is more than 1% and less than 10%, and the neutralization degree of the (methyl) acrylic acid in the ionomer resin is more than 50%.

Description

Tape for wafer processing and semiconductor processing method using same

technical field

The present invention relates to a wafer processing tape used in the manufacturing process of a semiconductor device and a semiconductor processing method using the wafer processing tape, and particularly relates to a dicing step of dividing a semiconductor wafer and a bonding layer using a high-speed rotating thin grindstone , and a dicing/die-attaching tape used in a die-attach process of picking up a semiconductor wafer that has been separated into pieces together with an adhesive layer that has been separated into pieces and stacking them on a substrate, and using the dicing・Semiconductor processing method of die attach tape.

Background technique

As a tape for wafer processing used in the manufacturing process of a semiconductor device, a dicing/die attaching tape (e.g. Patent Documents 1 to 3). Since these dicing/die attaching tapes contain a compound having an epoxy group in the adhesive layer (adhesive film), the semiconductor chip and the substrate can be firmly bonded by thermosetting. In addition, by making the adhesive layer of the dicing tape an energy ray curing type, the adhesive force of the dicing tape can be reduced by UV irradiation, etc., the interface between the adhesive layer and the adhesive layer can be easily peeled off, and the The semiconductor wafer into which the semiconductor chips are separated is picked up from the dicing tape together with the bonding layer which is separated into pieces by dicing.

For the above-mentioned dicing and die-attaching tape, it is required to have the performance that can reliably cut and singulate the semiconductor wafer and the bonding layer; pick up one by one, and provide it in the die-attaching process with a good yield rate, and The performance of firmly bonding the semiconductor chip to the substrate is also required.

However, in the above-mentioned dicing/die-attaching tape, when the semiconductor wafer is cut together with the adhesive layer by a thin grinding stone rotating at high speed, some of the adhesive layer that should be separated into pieces re-adheres, and when picking up A part of the semiconductor chip and an adjacent semiconductor chip are supplied to the die bonding process in a state of being connected, so-called "double chip pick-up error" occurs, and there is a disadvantage that the yield of the process deteriorates.

In order to suppress the occurrence of "two-die pick-up error", it is necessary to try to break the re-adhesion by at least expanding the gap between the semiconductor chips to a certain extent by expanding the dicing tape. Thus, the support substrate of the dicing tape is required to have uniform expansion and tension; Adhesive tapes composed of alkyl acrylate terpolymers or ionomer resins obtained by chelate crosslinking these substances with metal ions (for example, Patent Documents 4 to 8).

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2002-226796

Patent Document 2: Japanese Patent Laid-Open No. 2005-303275

Patent Document 3: Japanese Patent Laid-Open No. 2006-299226

Patent Document 4: Japanese Patent Application Laid-Open No. 5-156219

Patent Document 5: Japanese Patent Application Laid-Open No. 5-211234

Patent Document 6: Japanese Patent Laid-Open No. 2000-345129

Patent Document 7: Japanese Patent Laid-Open No. 2003-158098

Patent Document 8: Japanese Patent Laid-Open No. 2007-88240

Contents of the invention

The problem to be solved by the invention

However, even such a dicing tape does not necessarily have a sufficient effect of suppressing the occurrence of double-die pick-up errors, and there is a problem that double-die pick-up errors occasionally occur. Therefore, in order to further suppress the occurrence of two-chip pick-up errors, it is required to sufficiently suppress re-adhesion of semiconductor chips during pick-up.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a tape for wafer processing capable of sufficiently suppressing re-adhesion of semiconductor chips during pickup, and a semiconductor processing method using the tape for wafer processing.

The means used to solve the problem

The invention described in Claim 1 relates to a tape for wafer processing in which a thermosetting adhesive layer containing a compound having an epoxy group is laminated on the adhesive layer of an adhesive tape composed of a support base material and an adhesive layer. The tape for wafer processing is characterized by:

The above-mentioned support substrate is an ionomer resin obtained by cross-linking ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth)acrylic acid-alkyl (meth)acrylate terpolymer with metal ions constitute;

The weight fraction of the (meth)acrylic acid component in the copolymer is 1% to less than 10%, and the degree of neutralization of the (meth)acrylic acid in the ionomer resin is 50% or more.

The invention described in claim 2 relates to the tape for wafer processing according to claim 1, wherein the adhesive layer has a structure of one or more layers, at least one of which is formed of an energy ray-curable adhesive. .

The invention described in claim 3 relates to a semiconductor processing method using the tape for wafer processing according to claim 1 or 2, and the semiconductor processing method is characterized in that it includes the following steps:

A step of attaching a semiconductor wafer to the above-mentioned tape for wafer processing;

Next, the above-mentioned semiconductor wafer and the above-mentioned bonding agent layer and the above-mentioned adhesive layer of the above-mentioned wafer processing tape were cut using a thin grindstone rotating at a high speed, and at the same time, the above-mentioned supporting base material of the above-mentioned wafer processing tape was cut by 10 μm in the thickness direction. In the above, the step of singulating the semiconductor wafer and the bonding layer; and

Then, a step of picking up the singulated semiconductor wafers one by one in a state in which the tape of the adhesive tape for wafer processing is expanded.

The invention described in Claim 4 relates to the semiconductor processing method described in Claim 3, characterized in that the thickness of the above-mentioned supporting base material is 60 μm or more; .

The mechanism for accomplishing the present invention will be described below.

In the dicing process using a high-speed rotating thin grinding stone, the cause of the so-called "two-chip pick-up error" in which the bonding layer that should be separated into pieces is partially re-adhered occurs. Aggregates of chippings of the bonding agent layer that were chipped along with the wafers are clogged between adjacent semiconductor chips as shown in FIG. 6 , causing re-adhesion of adjacent semiconductor chips.

Such re-adhesion of adjacent semiconductor chips caused by swarf containing adhesive components may expand the dicing tape (adhesive tape) in the pick-up process, increasing the distance between semiconductor chips, and may break the re-adhesion. In order to expand the distance between all semiconductor chips, the support base material of the dicing tape is required to have uniform expandability. As such a support base material, ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth) ) acrylic acid-alkyl (meth)acrylate terpolymer, or any ionomer resin cross-linked with metal ions.

However, when the re-adhesion is strong, in order to break all the re-adhesion, only the uniform expandability of the supporting base material is not sufficient, and it is also necessary to embrittle the re-adhesion part.

If the compound having an epoxy group is removed from the adhesive layer of the dicing/die attach tape, the bonding performance in the shavings generated in the dicing process will decrease with the reduction of the adhesive performance due to the thermal curing of the adhesive layer. The adhesive force originating from the mixture component also decreases. As a result, the re-adhesion portion between adjacent semiconductor chips is also embrittled, and the occurrence of double-die pick-up errors can be suppressed. However, in this case, the adhesive force of the adhesive layer to the semiconductor chip will decrease, and the original Performance suffers.

Therefore, as a countermeasure for suppressing the occurrence of double-chip pick-up errors, a method is required to reduce semiconductor chips caused by cutting chips containing bonding agent components without reducing the compound having an epoxy group contained in the adhesive material layer. The re-adhesion of chips causes embrittlement.

The inventors of the present invention conducted intensive studies and found that by making the ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth)acrylic acid-(meth) The ratio of the (meth)acrylic acid component in the alkyl acrylate terpolymer is less than a specific amount, and ionomerization with metal ions can suppress the occurrence of double chip pick-up errors. By suppressing the (meth)acrylic acid component of the ionomer resin used in the support substrate and forming a stable complex with metal ions to reduce the reactivity, it is possible to suppress the carboxyl group of the (meth)acrylic component and the bonding agent layer. The reaction between compounds having epoxy groups reduces the adhesive force between the substrate chip components and the bonding agent chip components in the chip chips generated in the dicing process, and can make the semiconductor chips caused by chip chips Embrittlement occurs in the bonded part.

Substances that have the effect of providing sufficient uniform expandability to the support substrate and simultaneously suppressing the occurrence of double-chip pick-up errors are insufficient weight fractions of (meth)acrylic acid components in copolymers (copolymers, terpolymers) 10%, and the ionomer resin in which the degree of neutralization of (meth)acrylic acid in the ionomer resin is 50% or more, it is more preferable that the weight fraction of the (meth)acrylic acid component is 3% to 5%, and ( An ionomer resin with a neutralization degree of meth)acrylic acid of 50% or more.

If the weight fraction of the (meth)acrylic acid component in the copolymer in the support base material (ionomer resin) is 1% or more, the support base material can be expected to have uniform expandability; if it is 3% or more, further Uniform expandability of the supporting substrate is expected.

The weight fraction of the (meth)acrylic acid component in the copolymer in the ionomer resin can be quantified by combining NMR with methods such as thermal decomposition GC-ms spectrometry.

For example, the alkyl groups in the alkyl ester domains of ethylene-(meth)acrylic acid-alkyl(meth)acrylate terpolymers can be identified from the peaks in the pyrolysis GC-ms spectrum.

In addition, if ¹ H-NMR is used, the α-position hydrogen of the (meth)acrylic acid unit or the methyl group of the (meth)acrylic acid unit in the ionomer resin of the ethylene-(meth)acrylic acid binary copolymer can be The integral value of the hydrogen peak is compared with the integral value of the hydrogen peak of the ethylene unit, and quantified. When it is observed that the peak derived from the methyl group of the (meth)acrylic acid unit partially overlaps with the peak derived from the vinyl terminal or the ester terminal of the alkyl (meth)acrylate unit with a similar chemical shift, since the peak derived from Since the peak of the methyl group of the (meth)acrylic acid unit appears on the lower magnetic field side, the fraction of the (meth)acrylic acid component can be estimated from the integration on the lower magnetic field side. For ethylene-(meth)acrylic acid-alkyl(meth)acrylate terpolymers, it can also still be obtained by using ¹ H-NMR, according to the α position of (meth)acrylic acid and alkyl (meth)acrylate The peak of hydrogen or the methyl hydrogen of the (meth)acrylic acid unit quantifies the sum of the fraction of (meth)acrylic acid and the fraction of alkyl (meth)acrylate, further, for the alkyl (meth)acrylate As for the fraction of ester units, only the fraction of alkyl (meth)acrylate can be quantified based on the peak of hydrogen bonded to the 1-carbon of the alkyl group, and thus the weight fraction of (meth)acrylic acid can be calculated.

Furthermore, by using metal ions to make the neutralization degree of (meth)acrylic acid 50% or more, the (meth)acrylic acid component of the ionomer resin can be suppressed, and a stable complex can be formed with the metal ion to increase the reactivity. Reduces and can suppress the reaction between the carboxyl group of the (meth)acrylic acid component and the compound having an epoxy group in the adhesive layer, so it is possible to reduce the substrate chip component and the adhesive chip component in the cutting chips generated in the cutting process The adhesive force between them, so that the bonding part between the semiconductor chips caused by cutting chips is embrittled. As a result, it is possible to reliably suppress the occurrence of double chip pick-up errors. The neutralization degree of the said (meth)acrylic acid can be quantified by various spectroscopic analysis, such as ICP emission analysis. For example, the identification of metal ion species in ionomers and the quantification of their weight fractions can be performed simultaneously using ICP luminescence analysis. Further, if the method of combining the above-mentioned NMR with thermal decomposition GC-ms spectrometry is used to obtain the weight fraction of (meth)acrylic acid in the ionomer, it can be combined with the information of the above-mentioned metal ions to neutralize to quantify.

By applying such a support base material to wafer processing tapes such as dicing and die attach tapes, the occurrence of double chip pick-up errors can be suppressed, and the deeper the cut into the support base material in the dicing process, the greater the effect. big. On the other hand, if the cutting amount into the supporting base material is increased more than necessary, the adhesive tape may break when it expands.

If the amount of incision to the support base material is more than 10 μm in the thickness direction, it will have the effect of fully suppressing the generation of two-chip pick-up errors; if the support base material is cut below 30 μm in the thickness direction and the thickness of the support base material When it is 60 μm or more, it is possible to prevent the breakage of the supporting substrate.

In addition, by making the adhesive layer of the above-mentioned dicing/die-attach tape have a structure of one layer or more than two layers, at least one layer of which is formed of an energy ray-curable adhesive, it is possible to firmly hold the semiconductor in the dicing process. However, after dicing, the adhesive force of the dicing tape is effectively reduced by irradiating energy rays, so that an excessive load is not applied to the semiconductor chip during the pick-up process, and it is possible to The semiconductor chip and the singulated adhesive layer are easily peeled from the adhesive layer surface of the dicing tape.

Invention effect

If the tape for wafer processing of the present invention is used, since the weight fraction of the (meth)acrylic acid component in the copolymer is 1% or more and less than 10%, and the neutralization degree of the (meth)acrylic acid in the ionomer resin Since it is 50% or more, the re-adhesion of semiconductor chips can be fully suppressed at the time of pickup, and the generation|occurrence|production of a pick-up error of two chips can be suppressed further.

In addition, if the semiconductor processing method of the present invention is used, since the tape for wafer processing of the present invention is used, and in the process of singulating the semiconductor wafer and the bonding layer, the support base material of the tape for wafer processing is cut in the thickness direction. Since the chipping is 10 μm or more, re-adhesion between semiconductor chips can be further sufficiently suppressed during pick-up, and the occurrence of double-chip pick-up errors can be further suppressed.

Description of drawings

FIG. 1 is a cross-sectional view showing a schematic configuration of a dicing/die attach tape according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a schematic method of using the dicing/die attaching tape, and is a view of bonding a semiconductor wafer on the dicing/die attaching tape.

FIG. 3 is a view for explaining a subsequent step (cutting step) of FIG. 2 .

FIG. 4 is a diagram for explaining a subsequent step (expanding step) of FIG. 3 .

FIG. 5 is a diagram for explaining a subsequent process (pick-up process) of FIG. 4 .

FIG. 6 is an electron micrograph showing a mode in which chips generated during dicing are clogged between semiconductor chips.

Symbol Description

1 semiconductor wafer

2 semiconductor chips

10 Dicing/die attach tape (tape for wafer processing)

11 Release liner

12 cutting tape (adhesive tape)

12a Support substrate

12b adhesive layer

13 Adhesive layer

20 ring frame

21 thin grinding stone

22 adsorption table

30 upper part

31 pole (pin)

32 Adsorption fixture

Detailed ways

Embodiments of the present invention will be described in detail below based on the drawings.

In this embodiment, a dicing/die attach tape is exemplified as a tape for wafer processing and described.

FIG. 1 is a cross-sectional view showing a dicing/die attach tape 10 according to this embodiment.

As shown in FIG. 1 , the dicing die attach tape 10 is formed by laminating an adhesive layer 13 on a dicing tape 12 as an adhesive tape consisting of a support base 12 a and an adhesive layer formed thereon. agent layer 12b. FIG. 1 shows a state in which a release liner 11 is provided on the dicing/die attaching tape 10 in order to protect the adhesive layer 13 .

In addition, the pressure-sensitive adhesive layer 12b may be constituted by one pressure-sensitive adhesive layer, or may be constituted by a structure obtained by laminating two or more pressure-sensitive adhesive layers.

In addition, the dicing tape 12 and the adhesive layer 13 may be pre-cut into a predetermined shape (pre-cut, pricut) using a combination of processes or devices.

In addition, the dicing/die attaching tape 10 may be in the form of cutting for each semiconductor wafer, or may be in the form of winding a plurality of formed elongated sheets into a roll.

(How to use dicing and die attach tape)

In the manufacturing process of a semiconductor device, the dicing/die attach tape 10 is used as follows.

FIG. 2 shows a state where the semiconductor wafer 1 and the ring frame 20 are bonded on the dicing/die attaching tape 10 .

First, as shown in FIG. 2 , the dicing tape 12 is attached to the ring frame 20 , and the semiconductor wafer 1 is attached to the adhesive layer 13 . There is no limitation to their order of pasting, the dicing tape 12 can be pasted on the ring frame 20 after the semiconductor wafer 1 is bonded to the adhesive layer 13, and the pasting of the dicing tape 12 to the ring frame 20 and the semiconductor wafer 1 can also be carried out at the same time. Bonding to the adhesive layer 13 .

Moreover, the cutting process of the semiconductor wafer 1 is implemented using the thin grindstone 21 rotating at high speed (FIG. 3). At this time, the semiconductor wafer 1 is cut and divided together with the bonding agent layer 13 and the adhesive layer 12b, and the support base material 12a is cut at 10 μm to 30 μm in the thickness direction.

In addition, the surface of the semiconductor wafer 1 may be cut to a predetermined depth by one cut, or cut to a predetermined depth by multiple cuts.

Specifically, the dicing/die attaching tape 10 is sucked and supported by the suction table 22 from the side of the dicing tape 12 in order to cut the semiconductor wafer 1 and the bonding layer 13 using the thin grindstone 21 .

Then, the semiconductor wafer 1 and the bonding layer 13 are cut into semiconductor chip units by a thin grindstone 21 rotating at a high speed, and singulated.

In the case where the adhesive layer 12b of the dicing tape 12 has a structure of one layer or more than two layers, at least one layer of which is formed of an energy ray-curable adhesive, it is preferable to pass through the lower surface of the dicing tape 12 after the dicing process. The side (support base material 12a side) is irradiated with energy rays to cure the adhesive layer 12b and reduce its adhesive force.

In addition, when the pressure-sensitive adhesive layer 12b is composed of two or more pressure-sensitive adhesive layers by lamination, one or all of the layers in each pressure-sensitive adhesive layer may be formed of an energy-ray-curable pressure-sensitive adhesive. Curing is performed by irradiation of energy rays, and the adhesive force of the one layer or all the layers in each adhesive layer is reduced.

In addition, instead of irradiation of energy rays, the adhesive force of the dicing tape 12 may be reduced by external stimulation such as heating.

Thereafter, as shown in FIG. 4 , the dicing tape 12 holding the diced semiconductor wafer 1 (i.e., semiconductor chips 2 ) and the diced bonding agent layer 13 is stretched in the radial direction of the ring frame 20 to implement an expanding process. .

Specifically, for the dicing tape 12 in the state of holding a plurality of semiconductor chips 2 and the bonding agent layer 13, the upper top member 30 of the hollow cylindrical shape is raised from the lower side of the dicing tape 12, and the dicing tape 12 is moved toward the ring frame 20. stretched radially. Thus, the gap between the semiconductor chips 2 is enlarged through the expansion process, and the re-adhesion (re-adhesion) of the semiconductor chips 2 caused by the shavings generated in the dicing process is destroyed, and the double chip in the pick-up process can be prevented. The generation of picking errors.

After the expanding process is performed, as shown in FIG. 5 , a picking-up process of picking up the semiconductor chip 2 is performed while maintaining the expanded state of the dicing tape 12 .

Specifically, the semiconductor chip 2 is pushed up from the lower side of the dicing tape 12 by the support pin 31, and the semiconductor chip 2 is sucked from the upper side of the dicing tape 12 by the suction jig 32, thereby the semiconductor chip 2 is held together with the bonding agent layer 13. to pick up.

Then, after the pick-up process is performed, the chip attaching process is performed.

Specifically, the semiconductor chip 2 is bonded to a lead frame, a package substrate, or the like by the adhesive layer 13 (adhesive film) picked up together with the semiconductor chip 2 in the pick-up process, and is laminated.

Next, each constituent element of the dicing/die attach tape 10 of this embodiment will be described in detail.

(adhesive layer)

The adhesive layer 13 is bonded to the semiconductor wafer 1 or the like and diced, and when the semiconductor chip 2 is picked up, it is peeled off from the dicing tape 12 and attached to the semiconductor chip 2. 13 is used as a bonding agent. Therefore, in order to adhesively fix the semiconductor chip 2 to a substrate, a lead frame, or the like in the die attach process, the adhesive layer 13 needs to have sufficient adhesion reliability.

The adhesive layer 13 is a layer formed by preliminarily filming the adhesive, and contains at least one compound having an epoxy group, and may contain known polyimide resins, polyamide resins, polyether resins, polyester resins, etc. as needed. Resins, polyesterimide resins, phenoxy resins, polysulfone resins, polyphenylene sulfide resins, polyetherketone resins, chlorinated polypropylene resins, acrylic resins, polyurethane resins, epoxy resins, polyacrylamide resins , melamine resin, etc., or a polymer component such as a mixture thereof; an inorganic filler; or a curing accelerator. In addition, a silane coupling agent or a titanium coupling agent may be added as an additive in order to improve the adhesive force to a substrate, a lead frame, or the like.

The compound having an epoxy group is not particularly limited as long as it is cured to exhibit an adhesive action, but an epoxy resin having less than 500 to 5,000 difunctional groups or more is preferable. Examples of such epoxy resins include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, alicyclic epoxy resins, aliphatic chain epoxy resins, Novolak epoxy resin, cresol-novolak epoxy resin, bisphenol A novolac epoxy resin, diglycidyl ether of biphenol, diglycidyl ether of naphthalene diol, diphenols Glycidyl ether compounds, diglycidyl ether compounds of alcohols and their alkyl substitutes, halides, hydrides and other difunctional epoxy resins, novolac epoxy resins. In addition, generally known substances such as polyfunctional epoxy resins and heterocycle-containing epoxy resins can also be used.

These substances may be used alone or in combination of two or more.

Furthermore, components other than the epoxy resin may be contained as impurities within a range that does not impair the properties.

The thickness of the adhesive layer 13 is not particularly limited, but is generally preferably about 5 to 100 μm.

In addition, the adhesive layer 13 may be laminated on the entire surface of the dicing tape 12, or may be laminated with an adhesive film cut (pre-cut) into a shape corresponding to the semiconductor wafer 1 to be bonded to form the adhesive. Layer 13. In the case of laminating the adhesive film corresponding to the semiconductor wafer 1, as shown in FIG. The bonding agent layer 13 and only the dicing tape 12 are present. Generally speaking, since the adhesive layer 13 is not easy to be peeled off from the adherend, the ring frame 20 can be attached to the cutting tape 12 by using a pre-cut adhesive film, so that it is not easy to peel off the tape after use. The effect that the paste remains on the ring frame 20 (paste residue り).

(cutting tape)

The dicing tape 12 is such a tape: when the semiconductor wafer 1 is diced, it has sufficient adhesive force so that the semiconductor wafer 1 will not be peeled off; 13 Peeling such a low adhesive force, as shown in FIG. 1 , is a structure in which an adhesive layer 12b is provided on a support substrate 12a.

The support substrate 12a is an ionomer resin formed by cross-linking ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth)acrylic acid-(meth)acrylic acid alkyl ester terpolymer with metal ions. constitute.

The weight fraction of the (meth)acrylic acid component in the copolymer is not less than 1% and less than 10%, and the degree of neutralization of acrylic acid in the ionomer resin is not less than 50%.

Here, regarding the weight fraction of the (meth)acrylic acid component in the copolymer, when the support substrate 12a is composed of an ionomer resin obtained by cross-linking an ethylene-acrylic acid binary copolymer with metal ions, It is defined by "m·Mw _m /(n·Mw _n + m·Mw _m )" in Structural Formula 1 below.

In addition, when the support substrate 12a is composed of an ionomer resin obtained by cross-linking an ethylene-methacrylic acid binary copolymer with metal ions, it is defined as "b·Mw _b / (a·Mw _a +b·Mw _b )" to specify.

In addition, when the support substrate 12a is composed of an ionomer resin obtained by cross-linking an ethylene-acrylic acid-alkyl acrylate terpolymer with metal ions, it is defined as "m· Mw _m /(n·Mw _n +m·Mw _m +l·Mw ₁ )" is specified.

In addition, when the support substrate 12a is composed of an ionomer resin obtained by cross-linking an ethylene-methacrylic acid-alkyl methacrylate terpolymer with metal ions, it is formulated according to the following Structural Formula 4 "b·Mw _b /(a·Mw _a +b·Mw _b +c·Mw _c )" is specified.

In addition, the degree of neutralization of (meth)acrylic acid in the ionomer resin is specified as the degree to which the (meth)acrylic acid portion of the ionomer resin is ionized (neutralized) with metal ions (for example, Japan Journal of Rheology Society Vol.32, No.2, 65-69, 2004). In addition, m is m (that is, the number of repeating units of acrylic acid) in the following Structural Formula 1 or the following Structural Formula 3, and b is b (that is, the number of repeating units of methacrylic acid) in the following Structural Formula 2 or the following Structural Formula 4.

【Formula 1】

[Formula 2]

[Formula 3]

[Formula 4]

The type of metal ion in the ionomer resin is not particularly limited, but Zn ion is preferable from the viewpoint of contamination.

In addition, antioxidants, anti-blocking agents, leveling agents, etc. can also be added to the ionomer resin as needed.

The thickness of the supporting base material 12a is not particularly specified, and it is preferably 60 μm or more in view of the strength that the dicing tape 12 is expanded so as not to break as much as possible even when the supporting base material 12a is cut during dicing. thickness.

In addition, considering that the semiconductor chip 2 is pushed up from the lower side of the dicing tape 12 by the support pin 31 to promote the peeling of the bonding agent layer 13 and the adhesive layer 12b when picking up, it is preferable to support it from the rigidity of the base material. The thickness of the base material 12a is 150 μm or less.

In addition, in order to prevent the peeling of the adhesive layer 12b and the supporting substrate 12a, corona discharge or plasma irradiation, ultraviolet irradiation, or other activation treatments may be performed on the surface of the supporting substrate 12a before the adhesive layer 12b is laminated. .

In addition, on the lower surface of the support substrate 12a (the surface opposite to the surface on which the adhesive layer 12b is formed), in order to prevent the sticking of the dicing/die attaching tape 10 when it is wound in a roll, a fine surface may be provided on the surface. There are well-known coating methods such as unevenness and smoothness imparting.

The composition of the adhesive layer 12b is not particularly specified, as long as it is a layer that firmly holds the semiconductor wafer 1 during dicing and is easily peeled off from the adhesive layer 13 when picking up, but it is preferable to have one layer or two or more layers. A structure wherein at least one layer is formed of an energy ray-curable adhesive.

Moreover, the thickness of the adhesive layer 12b is not specifically limited, It can set suitably, Preferably it is 5-30 micrometers.

As the adhesive for forming the adhesive layer 12b, known chlorinated polypropylene resins, acrylic resins, polyester resins, polyurethane resins, epoxy resins, addition reaction organopolysiloxanes, etc. Oxane-based resins, silicone acrylate resins, ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl acrylate copolymers, ethylene-acrylic acid copolymers, polyisoprene or styrene-butylene Various elastomers such as a diene copolymer or its hydrogenated product, etc., or a mixture thereof are appropriately mixed with a radiation polymerizable compound to prepare. In addition, various surfactants or surface leveling agents can also be added.

As the above-mentioned radiation polymerizable compound, for example, a low-weight compound having at least two or more photopolymerizable carbon-carbon double bonds in the molecule, or a substituent having a photopolymerizable carbon-carbon double bond capable of forming a three-dimensional network by light irradiation is used. Polymers or oligomers based on carbon double bonds.

Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate; or oligoester acrylate, etc.; silicon acrylate, etc.; acrylic acid or various acrylate copolymers, etc.

In addition, urethane acrylate oligomers may also be used in addition to the above-mentioned acrylate compounds. The urethane acrylate oligomer is obtained by mixing a polyol compound such as a polyester type or a polyether type with a polyisocyanate compound (such as 2,4-tolyl diisocyanate, 2,6-tolyl diisocyanate, 1,3- xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, etc.) to react to obtain terminal isocyanate urethane prepolymer, so that the terminal isocyanate urethane Ester prepolymers and acrylates or methacrylates with hydroxyl groups (such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2- methacrylate Hydroxypropyl ester, polyethylene glycol acrylate, polyethylene glycol methacrylate, etc.) to react to obtain a polyurethane acrylate oligomer.

Moreover, as an adhesive which forms the adhesive layer 12b, what mixed 2 or more types selected from the said resin may be sufficient.

In addition, regarding the above-mentioned adhesive material mentioned as the adhesive agent forming the adhesive layer 12b, it is easy to perform peeling with the adhesive layer 13 containing a highly polar epoxy group. It is preferable to contain nonpolar groups such as trifluoromethyl groups, dimethylsilyl groups, and long-chain alkyl groups as much as possible in the molecular structure.

In addition, in the adhesive (resin) forming the adhesive layer 12b, in addition to the radiation-polymerizable compound that irradiates the adhesive layer 12b with radiation to cure the adhesive layer 12b, an acrylic adhesive may be appropriately mixed. Agents, photopolymerization initiators, curing agents, etc. to prepare.

In the case of using a photopolymerization initiator, for example, benzoin isopropyl ether (ISO PROPILLE BENZINE ETEL), benzoin isobutyl ether (ISOBU CHILLEBENZINE ETEL), benzophenone, and Michler's ketone can be used. , chlorothioxanthone, dodecyl thioxanthone, dimethyl thioxanthone, diethyl thioxanthone, benzoin dimethyl ether, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl propane etc.

According to the tape for wafer processing (dicing/die attaching tape 10) described above, the adhesive layer 12b of the dicing tape 12, which is an adhesive tape composed of the support base material 12a and the adhesive layer 12b, is laminated on the adhesive layer 12b containing The thermosetting adhesive layer 13 of an epoxy-based compound, the support substrate 12a is made of ethylene-(meth)acrylic acid binary copolymer or ethylene-(meth)acrylic acid-(meth)acrylic acid alkyl ester ternary The copolymer is composed of an ionomer resin cross-linked with metal ions, and the weight fraction of the (meth)acrylic acid component in the copolymer (copolymer, terpolymer) is 1% or more and less than 10%, and The degree of neutralization of (meth)acrylic acid in the ionomer resin is 50% or more.

Thereby, the supporting base material 12a has uniform expandability, and at the same time, the re-adhesion of the semiconductor chips 2 can be embrittled, so that the re-adhesion of the semiconductor chips 2 during pickup can be sufficiently suppressed, and the occurrence of double-chip pick-up errors can be further suppressed. .

In addition, according to the dicing/die attaching tape 10 described above, since the adhesive layer 13 contains a compound having an epoxy group, the semiconductor chip 3 can be firmly bonded to the substrate by the adhesive layer 13 .

In addition, according to the above-described dicing die-attach tape 10, since the adhesive layer 12b has a structure of one layer or more than two layers, at least one layer of which is formed of an energy ray-curable adhesive, it is possible to attach the semiconductor chip 2 The separated adhesive layer 13 is easily peeled from the surface of the adhesive layer 12b of the dicing tape 12 .

In addition, according to the semiconductor processing method using the dicing/die attaching tape 10 described above, it has the following steps: the step of attaching the semiconductor wafer 1 to the dicing/die attaching tape 10; The bonding agent layer 13 and the adhesive layer 12b of the semiconductor wafer 1 and the dicing/die-attaching tape 10 are cut, and at the same time, the supporting substrate 12a of the dicing/die-attaching tape 10 is cut by 10 μm or more in the thickness direction, and the semiconductor wafer 1 and the A process (dicing process) in which the bonding agent layer 13 is singulated; and next, the singulated semiconductor wafer 2 (that is, the semiconductor chip 1 ) and the singulated The formed adhesive layer 13 is picked up one by one (expansion process and pick-up process).

Therefore, since the dicing/die attaching tape 10 is used and the supporting base material 12a of the dicing/die attaching tape 10 is cut by 10 μm or more in the thickness direction in the dicing process, it is possible to further sufficiently suppress the reoccurrence of the semiconductor chips 2 when picking up. Sticking can further suppress the occurrence of double-die pick-up errors.

In addition, according to the semiconductor processing method using the dicing/die-attach tape 10 described above, the thickness of the supporting base material 12a is 60 μm or more, and in the singulation process (dicing process), the supporting base material 12a is cut in the thickness direction for 10 to 10 μm. 30 μm.

Therefore, since the thickness of the supporting base material 12a is 60 μm or more, and the supporting base material 12a is cut in the thickness direction by 10 to 30 μm in the dicing process, the supporting base material 12a has a strength that does not break even when the dicing tape 12 is expanded. Furthermore, re-adhesion of the semiconductor chips 2 at the time of pickup can be substantially completely suppressed.

Example

Examples of the present invention will be described below, but the present invention is not limited to these Examples.

Firstly, support substrates (substrate films) A to K are prepared, and an adhesive composition is prepared, and then the prepared adhesive composition is coated on the support substrate so that the thickness of the adhesive composition after drying is 20 μm, and dried at 110° C. for 3 minutes to produce an adhesive sheet (dicing tape) in which an adhesive layer was formed on a support substrate.

Next, an adhesive composition is prepared, and the prepared adhesive composition is coated on a release liner made of a polyethylene-terephthalate film that has been subjected to mold release so that the thickness after drying is 60 μm, dried at 110° C. for 3 minutes, and formed an adhesive film (adhesive bond layer) on a release liner.

In addition, after cutting the prepared adhesive sheet and adhesive film into the shape shown in FIG. 1, the adhesive film was attached to the adhesive layer side of the adhesive sheet to produce Examples 1 to 5 and Comparative Samples of Examples 1-6.

The production methods of the supporting substrates A to K, and the preparation methods of the adhesive composition and the adhesive composition are shown below.

(Supports the production of substrate A)

The weight fraction of the methacrylic acid component is 1%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 60% are melted at 140° C. using an extruder It was molded into a long-sized film with a thickness of 100 μm to obtain a support substrate A.

(Supports the production of base material B)

The weight fraction of the methacrylic acid component is 3%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 50% are melted at 140° C. using an extruder It was molded into a long film with a thickness of 100 μm to obtain a supporting base material B.

(Supports the production of substrate C)

The weight fraction of the methacrylic acid component is 5%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 50% are melted at 140° C. using an extruder It was molded into a long film with a thickness of 100 μm to obtain a support substrate C.

(Supports the production of substrate D)

The weight fraction of the methacrylic acid component is 9%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 60% are melted at 140° C. using an extruder It was molded into a long film with a thickness of 100 μm to obtain a support base D.

(Supports the production of substrate E)

The weight fraction of the methacrylic acid component is 9%, the weight fraction of the butyl methacrylate component is 12%, and the neutralization degree of the methacrylic acid is 70% of the ethylene-methacrylic acid-butyl methacrylate ternary The resin beads of the copolymer zinc ionomer were melted at 140° C. and molded into a long-sized film with a thickness of 100 μm using an extruder to obtain a supporting substrate E.

(Supports the production of substrate F)

The weight fraction of the methacrylic acid component is 10%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 60% are melted at 140° C. using an extruder It was molded into a long film with a thickness of 100 μm to obtain a supporting substrate F.

(Supports the production of substrate G)

Commercially available low-density polyethylene (Petrothene 217: manufactured by Tosoh Corporation) resin beads with a methacrylic acid content of 0% by weight was melted at 140°C and molded into a long film with a thickness of 100 μm using an extruder , to obtain the supporting substrate G.

(Supports the production of substrate H)

The resin beads of ethylene-methacrylic acid binary copolymer in which the methacrylic acid component is 5% by weight and the methacrylic acid neutralization degree is 0% are melted at 140° C., and molded into a thickness of 100 μm using an extruder In the form of a long-sized film, support substrate H was obtained.

(Support the production of substrate I)

The weight fraction of the methacrylic acid component is 9%, the neutralization degree of the methacrylic acid is 0%, and the ethylene-butyl methacrylate methacrylate terpolymerized resin beads are melted at 140° C., using an extruder It was molded into a long film with a thickness of 100 μm to obtain a support substrate I.

(Supports the production of substrate J)

The weight fraction of the methacrylic acid component is 1%, and the resin beads of the ethylene-methacrylic acid binary copolymer zinc ionomer having a neutralization degree of the methacrylic acid of 30% are melted at 140° C. using an extruder This was molded into a long film with a thickness of 100 μm to obtain a support substrate J.

(Supports the production of substrate K)

The resin beads of ethylene-methacrylic acid binary copolymer zinc ionomer having a methacrylic acid content of 5% by weight and a methacrylic acid neutralization degree of 40% were melted at 140° C. using an extruder It was molded into a long-sized film with a thickness of 100 μm to obtain a supporting substrate K.

(Preparation of Adhesive Composition)

In n-butyl acrylate/2-hydroxyethyl methacrylate copolymer (average molecular weight 500,000, glass transition temperature-40°C), add 20 parts by weight of trimethylolpropane trimethacrylate as a radioactive curing A compound of permanent carbon-carbon double bond, 7 parts by weight of polyisocyanate compound CORONETL (manufactured by Japan Polyurethane Co., Ltd., trade name) are many as curing agent, further add 5 parts by weight of Irgacure 184 (manufactured by Japan Ciba-Geigy Co., Ltd., trade name) As a photopolymerization initiator, a radiation curable adhesive composition was obtained.

(Preparation of cement composition)

In 100 parts by weight of acrylic copolymer (glycidyl acrylate copolymer), add 100 parts by weight of cresol-novolac epoxy resin as a compound with epoxy groups, further add 10 parts by weight of xylenol novolac In the type phenolic resin, mix 2-phenylimidazole (5 weight parts) and xylylene diamine (0.5 weight parts) as epoxy curing agent, and add the nano-silica filler (60 weight parts that the average particle diameter is 0.012 μm ) to obtain a cement composition.

<Example 1>

The adhesive composition prepared above was applied to the support substrate A to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Example 1.

<Example 2>

The adhesive composition prepared above was applied to the support substrate B to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Example 2.

<Example 3>

The adhesive composition prepared above was applied to the support substrate C to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Example 3.

<Example 4>

The adhesive composition prepared above was applied to the support substrate D to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Example 4.

<Example 5>

The adhesive composition prepared above was applied to the support substrate E to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Example 5.

<Comparative example 1>

The adhesive composition prepared above was applied to the support substrate F to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 1.

<Comparative example 2>

The adhesive composition prepared above was applied to the support substrate G to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 2.

<Comparative example 3>

The adhesive composition prepared above was applied to the support substrate H to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 3.

<Comparative example 4>

The adhesive composition prepared above was applied to the support substrate I to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 4.

<Comparative example 5>

The adhesive composition prepared above was applied to the support substrate J to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 5.

<Comparative example 6>

The adhesive composition prepared above was applied to the support substrate K to prepare a dicing tape, and the adhesive composition prepared above was laminated on the dicing tape to prepare a sample of Comparative Example 6.

<Evaluation method>

(pickup test)

A silicon wafer with a thickness of 50 μm and a diameter of 200 mm was heat-bonded to each sample of Examples 1 to 5 and Comparative Examples 1 to 6 at 70° C., and cut into a size of 5 mm×5 mm using a dicing device (DFD6340 manufactured by Disco). At this time, the adhesive layer and the adhesive layer of the dicing/die attach tape are cut and divided, and the support substrate is cut in the thickness direction at a predetermined depth (0 μm, 10 μm, 20 μm) and the device is further processed. Adjustment.

Next, each cut sample was irradiated with 200 mJ/cm ² of ultraviolet rays using a metal halide lamp.

Thereafter, for each sample, using a pick-up device (CAP-300II manufactured by Canon-Machinery), according to the method shown in FIG. In the pick-up test, the case where each semiconductor chip could be picked up one by one was counted as success. The case where two or more semiconductor chips were re-adhered and picked up was counted as failure.

The evaluation results are listed in Table 1 and Table 2.

Table 1

Table 2

From the results in Table 1, it can be seen that for the neutralization of (meth)acrylic acid in the ionomer resin to satisfy the weight fraction of the (meth)acrylic acid component in the copolymer in the support base material is more than 1% and less than 10%. For the samples of Examples 1 to 5 under the conditions of 50% or more, even without cutting the support base material, the occurrence of re-adhesion can be sufficiently suppressed when picking up; further, if the support base material is cut, the The occurrence of re-adhesion at the time of pickup can be further suppressed. In particular, it was found that when the support base material was cut by 20 μm in the thickness direction, the occurrence of re-adhesion at the time of pickup could be completely suppressed.

On the other hand, from the results of Table 2, it can be seen that the weight fraction of the (meth)acrylic acid component in the copolymer in the support base material is not less than 1% and less than 10%, and the (meth)acrylic acid component in the ionomer resin is not satisfied. ) for the samples of Comparative Examples 1 to 6 under the condition that the degree of neutralization of acrylic acid is 50% or more, in the case of not cutting the supporting base material, when picking up, the same as that of the samples of Examples 1 to 5 without cutting Re-adhesion occurs at the same rate or more in the case of the support substrate; even when the support substrate is cut, re-adhesion occurs when picking up.

According to the above content, if the weight fraction of the (meth)acrylic acid component in the copolymer in the supporting substrate is more than 1% and less than 10%, and the neutralization degree of the (meth)acrylic acid in the ionomer resin is 50 % or more, the occurrence of double chip pick-up errors can be sufficiently suppressed. Furthermore, it turned out that when the support base material was cut 10 micrometers or more in the thickness direction, the generation|occurrence|production of a two-chip pick-up error can be suppressed further.

Claims (4)

1. an adhesive tape for wafer processing, it is for by the adhesive tape for wafer processing of thermosetting cement layer that contains the compound with epoxy radicals of having supported lamination on this adhesive phase of the adhesive tape that base material and adhesive phase form, and this adhesive tape for wafer processing is characterised in that:

Above-mentioned support base material consists of the ionomer resin that ethene-(methyl) acrylic acid bipolymer or ethene-(methyl) acrylic acid-(methyl) alkyl acrylate terpolymer are formed by metal ion crosslinked;

The weight fraction of above-mentioned (methyl) acrylic component in above-mentioned copolymer is more than 1% and less than 10%, and above-mentioned (methyl) the acrylic acid degree of neutralization in above-mentioned ionomer resin is more than 50%.

2. adhesive tape for wafer processing as claimed in claim 1, is characterized in that, described adhesive phase has one deck or two layers of above structure, and at least one deck is wherein formed by energy ray-curable adhesive.

3. a semiconductor processing method, it is characterised in that for right to use requires the semiconductor processing method of the adhesive tape for wafer processing described in 1 or 2, this semiconductor processing method, it possesses following operation:

Semiconductor wafer is conformed to the operation of described adhesive tape for wafer processing;

Next use the slim grinding stone of High Rotation Speed to cut described cement layer and the described adhesive phase of described semiconductor wafer and described adhesive tape for wafer processing, simultaneously to the described support base material of this adhesive tape for wafer processing more than thickness direction cuts 10 μ m, this semiconductor wafer and this cement layer are carried out to the operation of singualtion; And

Then, under the state of expanding at the above-mentioned adhesive tape of above-mentioned adhesive tape for wafer processing, the operation of picking up the above-mentioned semiconductor wafer of singualtion blocks ofly.

4. semiconductor processing method as claimed in claim 3, is characterized in that:

The thickness of described support base material is more than 60 μ m;

In described singualtion operation, described support base material is cut to 10～30 μ m at thickness direction.

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