JP2005197630A - Method of manufacturing ic chip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of a manufacturing IC chip by which a wafer is prevented from breakage or the like, the handling property of the wafer is improved, and the wafer can be processed into IC chips with high productivity, even if the wafer is extremely thin with a thickness of 50 μm or thinner. <P>SOLUTION: The method of the manufacturing IC chip comprises a step 1 of fixing a wafer to a supporting plate via a double-sided adhesive tape, wherein an adhesive layer containing a gas-generating agent that generates gas by stimulation is formed on at least one side of the base member of the tape, a step 2 of grinding the wafer while the wafer is fixed to the supporting plate via the double-sided adhesive tape, and a step 3 of separating the wafer from the supporting plate by peeling the adhesive layer on the supporting-plate side of the double-sided adhesive tape from the base member by giving the stimulation. In the step 1 of the method of the manufacturing IC chip, the adhesive layer containing the gas-generating agent that generates the gas by giving stimulation to the double-sided adhesive tape is glued to the supporting plate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a method of manufacturing an IC chip that prevents damage to the wafer even when the wafer is very thin having a thickness of 50 μm or less, improves handling, and can be processed into an IC chip with high productivity.

A semiconductor integrated circuit (IC chip) is usually formed by slicing a rod-shaped high-purity semiconductor single crystal into a wafer, using a photoresist to form a predetermined circuit pattern on the wafer surface, and then grinding the backside of the wafer It is manufactured by grinding with a machine, reducing the thickness of the wafer to about 100 to 600 μm, and finally dicing into chips.

In such an IC chip manufacturing method, since the wafer is easily damaged particularly during grinding or dicing of the wafer, a support plate is attached to the wafer surface via a double-sided adhesive sheet when performing the grinding. In addition, when dicing is performed, the wafer is prevented from being damaged by attaching a dicing tape to the back side of the wafer. But,
Thus, the process of attaching or peeling the double-sided pressure-sensitive adhesive sheet or dicing tape is complicated, which has been a problem in terms of productivity of IC chips.

In recent years, as the use of IC chips has expanded, it can be used for IC cards or can be used by being stacked, and has a very thin thickness of 50 μm or less, for example, about 25 to 30 μm.
A C chip is also required, and it is considered that a thinner one will be required in the near future. However, such an ultra-thin semiconductor wafer is less warped than conventional wafers having a thickness of about 100 to 600 μm and is easily cracked by impact, and is similar to a conventional semiconductor wafer having a thickness. If you try to process with
There was a case where it was damaged. Therefore, from an ultra-thin semiconductor wafer with a thickness of 50 μm or less to IC
Improvement of the handleability of the wafer in the chip manufacturing process has been an important issue.

On the other hand, in Patent Document 1, a wafer is fixed to a support plate via a double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer containing a gas generating agent that generates a gas by stimulation on one side or both sides. An IC chip manufacturing method for performing a process such as grinding is disclosed. Even if the wafer is ground to an extremely thin thickness by being fixed to the support plate, the wafer is not damaged. Furthermore, after applying dicing tape to the ground wafer and applying a stimulus to generate gas, the generated gas peels off at least a part of the bonding surface between the wafer and the double-sided adhesive tape, thereby reducing the adhesive force. The support plate can be peeled without damaging the wafer. Thereafter, an IC chip having a thickness of about 50 μm can be efficiently produced by performing dancing by a normal method.

However, when the thickness of the wafer is made thinner than 50 μm, 30 μm, and 25 μm, the wafer is almost in a state of foil, which makes handling more difficult. Even with the method disclosed in Patent Document 1, there is a case where the ground wafer may be damaged due to an impact or the like when transferring the ground wafer to a dicing tape, and the yield of the product may be extremely reduced. There was a problem.

JP2003-231872

In view of the above situation, the present invention prevents the breakage of a wafer even if it is a very thin wafer having a thickness of 50 μm or less, improves handling, and manufactures an IC chip that can be processed into an IC chip with high productivity. It aims to provide a method.

The present invention includes a step 1 of fixing a wafer to a support plate via a double-sided pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer containing a gas generating agent that generates gas by stimulation is formed on at least one surface of a substrate; Step 2 of grinding the wafer in a state of being fixed to the support plate via an adhesive tape, and applying a stimulus to the support plate by peeling the adhesive layer on the support plate side of the double-sided adhesive tape from the substrate. An IC chip manufacturing method comprising a step 3 for separating a wafer, wherein in the step 1, the pressure-sensitive adhesive layer containing a gas generating agent that generates gas by stimulation of the double-sided pressure-sensitive adhesive tape and the support plate are provided. This is a method of manufacturing an IC chip to be bonded.
The present invention is described in detail below.

FIG. 1 is a schematic diagram showing one embodiment of the IC chip manufacturing method of the present invention. The IC chip manufacturing method of the present invention will be described below with reference to FIG.
The IC chip manufacturing method of the present invention includes a step 1 of fixing a wafer to a support plate via a double-sided adhesive tape. By fixing the wafer to the support plate, the handleability of the wafer is improved, and even when the wafer is ground to an extremely thin thickness of 50 μm or less, it can be handled very easily without being damaged. Processing into an IC chip can be performed.

The wafer is not particularly limited, and examples thereof include those made of a semiconductor such as silicon or gallium arsenide.
Although it does not specifically limit as said support plate, When the irritation | stimulation which generate | occur | produces gas from the gas generating agent mentioned later is light, it is preferable that it is transparent, for example, a glass plate; Acrylic, olefin, polycarbonate, vinyl chloride, ABS , Polyethylene terephthalate (PET),
Examples thereof include a plate-like body made of a resin such as nylon, urethane, or polyimide.

The surface of the support plate is preferably subjected to an adhesion improving treatment. By performing the adhesion improving treatment, the affinity with the adhesive layer of the double-sided pressure-sensitive adhesive tape is enhanced when the wafer is fixed via the double-sided pressure-sensitive adhesive tape. When peeling off, it can prevent more reliably that peeling arises between a base material and the adhesive layer by the side of a support plate, and adhesive layer remains on a base material.
It does not specifically limit as said adhesive improvement process, For example, conventionally well-known processing methods, such as a silane coupling agent process and a corona treatment, are mentioned.

A preferable lower limit of the thickness of the support plate is 500 μm, a preferable upper limit is 3 mm, a more preferable lower limit is 1 mm, and a more preferable upper limit is 2 mm. The thickness variation of the support plate is preferably 1% or less.

In the double-sided pressure-sensitive adhesive tape, a pressure-sensitive adhesive layer containing a gas generating agent that generates gas by stimulation is formed on at least one surface of a substrate.
Thereby, when the above-mentioned double-sided pressure-sensitive adhesive tape is stimulated, gas is generated from the gas generating agent in the pressure-sensitive adhesive layer, and the generated gas peels at least a part between the pressure-sensitive adhesive layer and the adherend. Thus, the adhesive force is reduced and can be easily peeled off.
In addition, when a gas generating agent is contained in the pressure-sensitive adhesive layers on both sides, the gas generating agents on both sides may be the same or different.

Examples of the stimulus for generating gas from the gas generating agent include stimulation by light, heat, and ultrasonic waves. Of these, stimulation by light or heat is preferred. Examples of the light include ultraviolet rays and visible rays. When light stimulation is used as the stimulation, the pressure-sensitive adhesive containing the gas generating agent is preferably capable of transmitting or passing light.

Although it does not specifically limit as a gas generating agent which generate | occur | produces gas by the said irritation | stimulation, For example, an azo compound and an azide compound are used suitably.
Examples of the azo compound include 2,2′-azobis (N-cyclohexyl-2-methylpropionamide), 2,2′-azobis [N- (2-methylpropyl) -2-methylpropionamide], 2 , 2'-azobis (N-butyl-2-methylpropionamide)
2,2′-azobis [N- (2-methylethyl) -2-methylpropionamide], 2
, 2′-azobis (N-hexyl-2-methylpropionamide), 2,2′-azobis (N-propyl-2-methylpropionamide), 2,2′-azobis (N-ethyl-2)
-Methylpropionamide), 2,2'-azobis {2-methyl-N- [1,1-bis (
Hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2′-azobis {2-methyl-N- [2- (1-hydroxybutyl)] propionamide}, 2,2′-
Azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-
Azobis [N- (2-propenyl) -2-methylpropionamide], 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride,
2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane] disulfate dihydrolate, 2 , 2′-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2′-azobis {2- [1- (
2-hydroxyethyl) -2-imidazolin-2-yl] propane} dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane], 2,2′-azobis (2-methylpropion) Amidine) hydrochloride, 2,2′-azobis (2-
Aminopropane) dihydrochloride, 2,2′-azobis [N- (2-carboxyacyl) -2-methyl-propionamidine], 2,2′-azobis {2- [N- (2-carboxyethyl) amidine ] Propane}, 2,2′-azobis (2-methylpropionamidoxime), dimethyl 2,2′-azobis (2-methylpropionate), dimethyl 2,2′-azobisisobutyrate, 4,4 Examples include '-azobis (4-cyancarbonic acid), 4,4'-azobis (4-cyanopentanoic acid), and 2,2'-azobis (2,4,4-trimethylpentane).
These azo compounds generate nitrogen gas mainly by irradiating light in the ultraviolet region with a wavelength of about 365 nm.

The azo compound preferably has a 10-hour half-life temperature of 80 ° C. or higher. When the 10-hour half-life temperature is less than 80 ° C., the pressure-sensitive adhesive tape of the present invention may cause foaming when it is dried by forming a pressure-sensitive adhesive layer by casting, or a decomposition reaction may occur over time. May bleed out, or may generate gas over time and cause floating at the interface with the adherend. If the 10-hour half-life temperature is 80 ° C. or higher, the heat resistance is excellent, and therefore, use at a high temperature and stable storage are possible.

Examples of the azo compound having a 10-hour half-life temperature of 80 ° C. or higher include an azoamide compound represented by the following general formula (1). The azoamide compound represented by the following general formula (1) is:
In addition to being excellent in heat resistance, it is also excellent in solubility in an adhesive polymer such as an alkyl acrylate polymer to be described later, and cannot be present as particles in the adhesive layer.

式（１）中、Ｒ^１及びＲ^２は、それぞれ低級アルキル基を表し、Ｒ^３は、炭素数２以上の
飽和アルキル基を表す。なお、Ｒ^１とＲ^２は、同一であっても、異なっていてもよい。

In formula (1), R ¹ and R ² each represent a lower alkyl group, and R ³ represents a saturated alkyl group having 2 or more carbon atoms. R ¹ and R ² may be the same or different.

Examples of the azoamide compound represented by the general formula (1) include 2,2′-azobis (
N-cyclohexyl-2-methylpropionamide), 2,2′-azobis [N- (2-
Methylpropyl) -2-methylpropionamide], 2,2′-azobis (N-butyl-
2-methylpropionamide), 2,2′-azobis [N- (2-methylethyl) -2-
Methylpropionamide], 2,2′-azobis (N-hexyl-2-methylpropionamide), 2,2′-azobis (N-propyl-2-methylpropionamide), 2,2
'-Azobis (N-ethyl-2-methylpropionamide), 2,2'-azobis {2-
Methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2′-azobis {2-methyl-N- [2- (1-hydroxybutyl)] propionamide} 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] and the like. Among these, 2,2′-azobis (N-butyl-2-methylpropionamide) and 2,2′-azobis [N- (2-propenyl) -2-methylpropionamide] have improved solubility in solvents. It is preferably used because it is particularly excellent.

Examples of the azide compound include 3-azidomethyl-3-methyloxetane, terephthalazide, p-tert-butylbenzazide; glycidyl azide polymer obtained by ring-opening polymerization of 3-azidomethyl-3-methyloxetane, and the like. Examples thereof include a polymer having an azide group. These azide compounds generate nitrogen gas mainly by irradiating light in the ultraviolet region with a wavelength of about 365 nm.

Among these gas generating agents, the azide compound is easily decomposed even by giving an impact and releases nitrogen gas, so that there is a problem that handling is difficult. Furthermore, once the decomposition starts, the azide compound causes a chain reaction and explosively releases nitrogen gas, which cannot be controlled. Therefore, the adherend may be damaged by the explosively generated nitrogen gas. There is also a problem. Due to such problems, the amount of the azide compound used is limited,
A sufficient amount may not be obtained with a limited use amount.

On the other hand, unlike the azide compound, the azo compound is extremely easy to handle because it does not generate gas upon impact. In addition, since the chain reaction does not generate gas explosively, the adherend is not damaged, and the generation of gas can be interrupted if the irradiation of ultraviolet rays is interrupted. There is also an advantage that control is possible. Therefore, it is more preferable to use an azo compound as the gas generating agent.

The gas generating agent is preferably not present as particles in the pressure-sensitive adhesive layer. In addition, in this specification, that a gas generating agent does not exist as a particle | grain means that a gas generating agent cannot be confirmed when the said adhesive layer is observed with an electron microscope. When the gas generating agent is present as particles in the pressure-sensitive adhesive layer, when light is irradiated as a gas generating stimulus, light is scattered at the particle interface, resulting in low gas generation efficiency. The surface smoothness may deteriorate.

In order to prevent the gas generating agent from being present as particles, normally, a gas generating agent that dissolves in the adhesive constituting the adhesive layer is selected, but when a gas generating agent that does not dissolve in the adhesive is selected. For example, the gas generating agent is finely dispersed in the pressure-sensitive adhesive layer by using a disperser or using a dispersing agent in combination. In order to finely disperse the gas generating agent in the pressure-sensitive adhesive layer, the gas generating agent is preferably fine particles, and these fine particles are necessary using, for example, a disperser or a kneading apparatus. Accordingly, finer fine particles are preferable. That is, it is more preferable to disperse the gas generating agent to a state where it cannot be confirmed when the pressure-sensitive adhesive layer is observed with an electron microscope.

In the double-sided pressure-sensitive adhesive tape, the gas generated from the gas generating agent is preferably released out of the pressure-sensitive adhesive layer. As a result, when the adhesive surface of the double-sided pressure-sensitive adhesive tape is irradiated with ultraviolet rays or the like, the gas generated from the gas generating agent peels off at least a part of the adhesive surface and lowers the adhesive force. At this time, it is preferable that most of the gas generated from the gas generating agent is released out of the pressure-sensitive adhesive layer. If most of the gas generated from the gas generating agent is not released to the outside of the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is foamed entirely by the gas generated from the gas generating agent, and the effect of reducing the adhesive force is sufficient. May not be obtained, resulting in adhesive residue. As long as no adhesive residue is generated, a part of the gas generated from the gas generating agent may be dissolved in the pressure-sensitive adhesive layer or may be present as bubbles in the pressure-sensitive adhesive layer.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is preferably one that is crosslinked by stimulation and has an increased elastic modulus. By using such an adhesive, it is possible to make the peeling easier by reducing the adhesive force by increasing the elastic modulus by giving a stimulus at the time of peeling. Furthermore, if the cross-linking is performed prior to the generation of gas at the time of peeling, the elastic modulus of the entire pressure-sensitive adhesive layer will increase, and if gas is generated from the gas generating agent in a hard cured product with an increased elastic modulus, Most of the gas thus discharged is released to the outside, and the released gas peels off at least a part of the adhesive surface of the pressure-sensitive adhesive layer and reduces the adhesive force.
The stimulus for crosslinking the pressure-sensitive adhesive may be the same as or different from the stimulus for generating gas from the gas generating agent. When the stimuli are different, a stimulus for cross-linking the cross-linking component is given before giving a stimulus for generating gas from the gas generating agent at the time of peeling. Even when the stimulation is the same, gas is usually generated from the gas generating agent, and there is a time lag before it is released from the pressure-sensitive adhesive layer, leading to an increase in the elastic modulus due to the crosslinking reaction.

As such an adhesive, for example, an acrylic acid alkyl ester-based and / or methacrylic acid alkyl ester-based polymerizable polymer having a radical polymerizable unsaturated bond in the molecule, and a radical polymerizable polyfunctional A photo-curing pressure-sensitive adhesive comprising an oligomer or a monomer as a main component and containing a photopolymerization initiator as necessary, an alkyl acrylate ester having a radical polymerizable unsaturated bond in the molecule, and / or Alternatively, a methacrylic acid alkyl ester-based polymerizable polymer and a radical polymerizable polyfunctional oligomer or monomer as main components and a thermosetting pressure-sensitive adhesive containing a thermal polymerization initiator can be used.

The pressure-sensitive adhesive layer comprising a post-curing pressure-sensitive adhesive such as a photo-curing pressure-sensitive adhesive or a thermosetting pressure-sensitive adhesive,
Since the entire pressure-sensitive adhesive layer is uniformly and rapidly polymerized and cross-linked and integrated by light irradiation or heating, the elastic modulus is remarkably increased by polymerization and curing, and the adhesive strength is greatly reduced. In addition, when a gas is generated from a gas generating agent in a hard cured product having an increased elastic modulus, most of the generated gas is released to the outside, and the released gas is at least part of the adhesive surface of the pressure-sensitive adhesive layer. Peel and reduce adhesion.

The polymerizable polymer is, for example, a (meth) acrylic polymer having a functional group in the molecule (
Hereinafter, a functional group-containing (meth) acrylic polymer) is synthesized in advance, and a compound having a functional group that reacts with the above functional group and a radical polymerizable unsaturated bond in the molecule (hereinafter referred to as a functional group-containing unsaturated group). It can be obtained by reacting with a compound).

The functional group-containing (meth) acrylic polymer is a polymer having adhesiveness at room temperature,
As in the case of a general (meth) acrylic polymer, the alkyl group usually has 2 to 18 carbon atoms.
An acrylic acid alkyl ester and / or methacrylic acid alkyl ester in the range of is used as a main monomer, and this, a functional group-containing monomer, and, if necessary, other modifying monomers copolymerizable with these by a conventional method. It is obtained by copolymerization. The weight average molecular weight of the functional group-containing (meth) acrylic polymer is usually about 200,000 to 2,000,000.

Examples of the functional group-containing monomer include a carboxyl group-containing monomer such as acrylic acid and methacrylic acid; a hydroxyl group-containing monomer such as hydroxyethyl acrylate and hydroxyethyl methacrylate; and an epoxy group containing glycidyl acrylate and glycidyl methacrylate. Monomers; Isocyanate group-containing monomers such as isocyanate ethyl acrylate and isocyanate ethyl methacrylate; and amino group-containing monomers such as aminoethyl acrylate and aminoethyl methacrylate.
Examples of other modifying monomers that can be copolymerized include various monomers used in general (meth) acrylic polymers such as vinyl acetate, acrylonitrile, and styrene.

The functional group-containing unsaturated compound to be reacted with the functional group-containing (meth) acrylic polymer is the same as the functional group-containing monomer described above according to the functional group of the functional group-containing (meth) acrylic polymer. it can. For example, when the functional group of the functional group-containing (meth) acrylic polymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used, and when the functional group is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group is an epoxy group, a carboxyl group-containing monomer or an amide group-containing monomer such as acrylamide is used, and when the functional group is an amino group, an epoxy group-containing monomer is used.

As the polyfunctional oligomer or monomer, those having a molecular weight of 10,000 or less are preferable,
More preferably, the molecular weight is 5,000 or less and the number of radically polymerizable unsaturated bonds in the molecule is 2 to 2 so that the three-dimensional network of the pressure-sensitive adhesive layer by heating or light irradiation can be efficiently performed.
There are 20 things. As such a more preferred polyfunctional oligomer or monomer,
Examples thereof include trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, and the same methacrylates as described above. Other, 1
, 4-butylene glycol diacrylate, 1,6-hexanediol diacrylate,
Examples include polyethylene glycol diacrylate, commercially available oligoester acrylate, and methacrylates similar to those described above. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.

Examples of the photopolymerization initiator include those activated by irradiation with light having a wavelength of 250 to 800 nm. Examples of such a photopolymerization initiator include acetophenone derivative compounds such as methoxyacetophenone. Benzoin ether compounds such as benzoin propyl ether and benzoin isobutyl ether; ketal derivative compounds such as benzyl dimethyl ketal and acetophenone diethyl ketal; phosphine oxide derivative compounds; bis (η5-cyclopentadienyl) titanocene derivative compounds, benzophenone, Michler's ketone Chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, 2-
Examples include photo radical polymerization initiators such as hydroxymethylphenylpropane. These photoinitiators may be used independently and 2 or more types may be used together.

Examples of the thermal polymerization initiator include those that decompose by heat and generate an active radical that initiates polymerization and curing, such as dicumyl peroxide, di-t-butyl peroxide,
Examples thereof include t-butyl peroxybenzoate, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, and di-t-butyl peroxide. Among these, cumene hydroperoxide, paramentane hydroperoxide, di-t-butyl peroxide, and the like are preferable because of their high thermal decomposition temperature. Although it does not specifically limit as what is marketed among these thermal-polymerization initiators, For example, perbutyl D, perbutyl H, perbutyl P, permenta H (all are the products made from NOF) etc. are suitable. These thermal polymerization initiators may be used independently and 2 or more types may be used together.

In addition to the above components, the post-curing pressure-sensitive adhesive described above is variously blended with general pressure-sensitive adhesives such as isocyanate compounds, melamine compounds, and epoxy compounds as desired for the purpose of adjusting the cohesive force as the pressure-sensitive adhesive. You may mix | blend a polyfunctional compound suitably. Moreover, well-known additives, such as a plasticizer, resin, surfactant, wax, and a fine particle filler, can also be added.

The base material of the double-sided pressure-sensitive adhesive tape is not particularly limited as long as it has flexibility. For example, acrylic, olefin, polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), nylon, urethane, polyimide, etc. Examples thereof include a sheet made of a transparent resin, a sheet having a network structure, and a sheet having holes. Further, when it is desired to prevent light from reaching the pressure-sensitive adhesive layer that is bonded to the wafer, carbon black or the like may be blended to make it opaque.

The base material is preferably subjected to a release treatment on the surface to be bonded to the support plate. By performing the mold release treatment, when the support plate and the wafer are peeled in the step 3 described below, the peeling occurs more reliably between the base material and the pressure-sensitive adhesive layer on the support plate side. It is possible to prevent the adhesive layer from remaining on the base material. The mold release treatment is not particularly limited, and conventionally known treatment methods can be mentioned.
In addition, the base material may be subjected to an adhesion improving process on the surface to be bonded to the wafer. By performing the adhesion improving process, it is possible to prevent the adhesive from remaining on the wafer when the substrate is peeled off from the wafer later. The adhesive improvement treatment is not particularly limited,
For example, corona treatment; treatment for forming an adhesion primer layer made of urethane resin, etc .; treatment for kneading a fine filler or the like on the surface of a substrate to give a fine embossed pattern; treatment for giving a fine embossed pattern by sandblasting, etc. Etc.

As a result of applying such an adhesion improving treatment to the base material, 180 ° required in accordance with the 180 ° peel strength test of JIS K 6854 between the base material on the side subjected to the adhesive improving treatment and the pressure-sensitive adhesive layer. It is preferable that the peel adhesive strength is 300 N / m or more. If it is less than 300 N / m, adhesive residue may be generated on the wafer during peeling.
On the other hand, the preferable lower limit of the 180-degree peel adhesive strength between the base material on the side not subjected to the adhesion improvement treatment and the pressure-sensitive adhesive layer is 1 N / m, and the preferable upper limit is 100 N / m. If it is less than 1 N / m, the adhesive force between the support plate and the wafer may be insufficient and may be peeled off during the grinding process,
If it exceeds 100 N / m, the adhesive layer may remain on the substrate when the support plate is peeled off from the wafer in step 3.

Although it does not specifically limit as thickness of the said base material, A preferable minimum is 10 micrometers and a preferable upper limit is 300 micrometers. If it is less than 10 μm, the self-supporting property of the double-sided pressure-sensitive adhesive tape may be insufficient and handling may be difficult, or the effect of holding the wafer may not be obtained.
If it exceeds 300 μm, a problem may occur when the double-sided pressure-sensitive adhesive tape is peeled off.

The method for producing the double-sided pressure-sensitive adhesive tape is not particularly limited. For example, a method of applying a pressure-sensitive adhesive containing the gas generating agent or the like on the base material using a doctor knife, a spin coater, or the like. Can be mentioned.

In the method for producing an IC chip of the present invention, in step 1, the pressure-sensitive adhesive layer containing a gas generating agent that generates gas by stimulation of the double-sided pressure-sensitive adhesive tape and the support plate are bonded together. By adopting such a configuration, it is possible to surely peel off the adhesive surface between the pressure-sensitive adhesive layer on the side of the support plate and the substrate by giving a stimulus. When the gas generating agent is contained only in the pressure-sensitive adhesive layer to be bonded to the wafer, peeling occurs between the wafer and the pressure-sensitive adhesive layer when a stimulus is applied.

In the embodiment of the present invention shown in FIG. 1, the wafer 1 is fixed to the support plate 2 via a double-sided adhesive tape 3 (FIG. 1a). In Step 4 to be described later, in order to separate the support plate and the wafer by separating the adhesive layer on the support plate side of the double-sided adhesive tape from the base material, at least the support plate 2 of the double-sided adhesive tape 3 is attached. The gas generating agent must be contained in the pressure-sensitive adhesive layer 321 on the matching side. Furthermore, in order to ensure separation without adhesive residue, the adhesive strength at the interface between the support plate and the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape is It needs to be higher than the adhesive strength at the interface with the substrate. The relationship between the adhesive strengths at the respective interfaces can be said not only at the time of application in step 1 but also immediately before applying a stimulus in step 3 described later, and when the support plate and the wafer are separated.
For this purpose, specifically, for example, the surface of the support plate 2 is subjected to an adhesion improving process and / or the surface of the base 31 on the side to be bonded to the support plate 2 is subjected to a mold release process. It is preferable.
Furthermore, since it is necessary to completely peel off the double-sided pressure-sensitive adhesive tape from the wafer, the adhesive strength at the interface between the base material 31 and the pressure-sensitive adhesive layer 322 is the adhesion at the interface between the wafer 1 and the pressure-sensitive adhesive layer 322. It is preferably higher than strength. This can be realized by an adhesion improving process that is usually applied to a substrate.

The IC chip manufacturing method of the present invention includes a step 2 of grinding a wafer while being fixed to a support plate via a double-sided adhesive tape.
The grinding method is not particularly limited, and a method used in a normal IC chip manufacturing method can be used. For example, while fixing a support plate and applying cutting water using a grinding wheel that rotates at high speed, For example, a method of grinding the wafer to the thickness of the chip at the time of completion can be mentioned.
By the above step 2, the wafer 1 is ground to a predetermined thickness while being fixed to the support plate 2 via the double-sided adhesive tape 3 (FIG. 1b).

The manufacturing method of the IC chip of the present invention includes a step 3 of separating the support plate and the wafer by giving a stimulus and separating the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape from the substrate.
In the embodiment shown in FIG. 1, among the four interfaces A, B, C, and D shown in FIG.
It peels in the interface B of the surface at the side of the support plate, and the adhesion layer 321. Thereby, the support plate 2 is separated together with the pressure-sensitive adhesive layer 321, and a structure in which the ground wafer 1 as shown in FIG. 1C is bonded to the base material 31 via the pressure-sensitive adhesive layer 322 is left behind. In such a structure, an extremely thin wafer that has been ground is supported by the base material, so that it is extremely difficult to break and handling becomes easy.

By stimulating the double-sided pressure-sensitive adhesive tape, gas is generated from the gas generating agent in the pressure-sensitive adhesive layer. At this time, the pressure-sensitive adhesive on the support plate side of the double-sided pressure-sensitive adhesive tape is adjusted by adjusting the presence or absence of the gas generating agent in the pressure-sensitive adhesive layer on the wafer side of the double-sided pressure-sensitive adhesive tape, the selection of the type and content thereof, and the way to give the stimulus. Separation occurs only between the layer and the substrate (interface B in FIG. 1b), and a structure in which the ground wafer is supported by the substrate can be obtained.
For example, when the gas generating agent is contained only in the pressure-sensitive adhesive layer on the surface on the support plate side,
By giving a stimulus, the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape can be peeled off from the base material, and the support plate and the wafer can be separated.
Further, for example, when the gas generating agent is contained in the pressure-sensitive adhesive layers on both sides, the gas generating agents contained in the respective pressure-sensitive adhesive layers are different from each other, and the stimulus for generating the gas is different. In some cases, only the stimulus for generating gas from the gas generating agent contained in the pressure-sensitive adhesive layer on the support plate side is given. For example, if the gas generating agent on the support plate side generates gas by light irradiation, and the gas generating agent on the wafer side generates gas by heating, light is irradiated. In addition, when using the said azo compound and azide compound as a gas generating agent, gas is generated by light irradiation and heating. In this case, for example, by forming a structure that does not transmit light by blending carbon black or the like in the base material, gas can be generated only from the pressure-sensitive adhesive layer on the support plate side when irradiated with light. it can.
Further, for example, when the gas generating agent is contained in the pressure-sensitive adhesive layers on both sides, the gas generating agents contained in the respective pressure-sensitive adhesive layers are of the same type, and the stimulation for generating gas is the same. In the case of light, it is possible to generate gas only from the gas generating agent in the pressure-sensitive adhesive layer on the side close to the support plate by adjusting the light irradiation intensity. In addition, by adjusting the content of the gas generating agent contained in the pressure-sensitive adhesive layer so that the supporting plate side is increased, gas is generated only from the gas generating agent in the pressure-sensitive adhesive layer on the side close to the supporting plate. Is possible.

When gas is generated from the gas generating agent of the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape, the generated gas is released to the adhesive surface between the pressure-sensitive adhesive layer and the base material, and peels at least a part of the adhesive surface. Reduce. At this time, between the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape and the base material more reliably (
In order to cause the separation only at the interface B) in FIG. 1b, the separation between the support plate and the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape immediately before applying the stimulus and when the support plate and the wafer are separated. The adhesive strength at the interface (interface A in FIG. 1b) is preferably higher than the adhesive strength at the interface between the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape and the substrate (interface B in FIG. 1b).
In order to provide a difference in the adhesive strength at the two interfaces in this way, for example, as described above, the support plate is subjected to an adhesive improvement treatment, or the mold release treatment is performed on the surface of the base material to be bonded to the support plate. Is preferably applied. When any one of these treatments is performed, peeling can be more reliably caused at the interface between the pressure-sensitive adhesive layer and the base material (interface B in FIG. 1b), and adhesive residue can be generated on the base material. Absent.

In the structure thus obtained, since the wafer is supported by the base material, it is not easily damaged, and is extremely easy to handle.
The subsequent steps are not particularly limited. For example, it is conceivable to etch the ground surface of the wafer or form a thin film. In particular, by using a material having excellent heat resistance and chemical resistance such as polyethylene terephthalate as the base material, these operations can be performed stably.
Further, before and after the step 3, a dicing tape may be applied to the ground wafer. When a dicing tape is attached before step 3, after the support plate and the wafer are separated in step 3, a structure in which the ground wafer is sandwiched between the dicing tape and the substrate is left. Become. Such a structure is further excellent in handleability.
Although it does not specifically limit as said dicing tape, For example, a conventionally well-known photocurable adhesive tape etc. can be used. Examples of the currently commercially available photo-curable adhesive tape include tapes such as Adwill (registered trademark) D-series manufactured by Lintec Corporation and ELEP Holder (registered trademark) UE series manufactured by Nitto Denko Corporation.

Finally, after removing the substrate from the wafer, dicing is performed to obtain an IC chip.
Since the substrate has flexibility, it can be easily peeled off. At this time, since no adhesive remains on the surface of the substrate, the operation is extremely easy. Moreover, when the gas generating agent is contained in the pressure-sensitive adhesive layer on the wafer side of the base material or the photo-curing pressure-sensitive adhesive is used, the base material can be more easily separated from the wafer.
The dicing method is not particularly limited. For example, a method of cutting and separating using a conventionally known grindstone or the like can be used.

According to the IC chip manufacturing method of the present invention, since the wafer is fixed to the support plate via the double-sided adhesive tape, even if the wafer is ground to an extremely thin thickness of 50 μm or less, it can be easily handled and damaged. Absent. In addition, when transferring the ground wafer to the dancing tape, the support plate is peeled off together with one of the adhesive layers, and the wafer is sandwiched between the base material and the dicing tape, so that the wafer can be impacted. The wafer is not damaged.

According to the present invention, there is provided an IC chip manufacturing method capable of preventing breakage of a wafer, improving handleability, and processing into an IC chip with high productivity even for a very thin wafer having a thickness of about 50 μm. it can.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited only to these examples.

(Example 1)
<Preparation of adhesive>
The following compounds are dissolved in ethyl acetate and polymerized by irradiating with ultraviolet rays to give a weight average molecular weight of 7
0,000 acrylic copolymer was obtained.
2 parts by weight per 100 parts by weight of the resin solid content of the ethyl acetate solution containing the obtained acrylic copolymer
-3.5 parts by weight of isocyanatoethyl methacrylate was added to react, and further, 40 parts by weight of U324A (manufactured by Shin-Nakamura Chemical Co., Ltd.) with respect to 100 parts by weight of the resin solid content of the ethyl acetate solution after the reaction was started 5 parts by weight of the agent (Irgacure 651) and 0.5 parts by weight of polyisocyanate were mixed to prepare an ethyl acetate solution of the pressure-sensitive adhesive (1).
Butyl acrylate 79 parts by weight Ethyl acrylate 15 parts by weight Acrylic acid 1 part by weight 2-hydroxyethyl acrylate 5 parts by weight Photopolymerization initiator 0.2 part by weight (Irgacure 651, 50% ethyl acetate solution)
Lauryl mercaptan 0.01 parts by weight

In addition, 30 parts by weight of 2,2′-azobis- (N-butyl-2-methylpropionamide) and 2,4-, with respect to 100 parts by weight of the resin solid content of the ethyl acetate solution of the pressure-sensitive adhesive (1) A pressure-sensitive adhesive (2) containing a gas generating agent was prepared by mixing 3.6 parts by weight of diethylthioxanthone.

<Production of double-sided adhesive tape>
One side of a 50 μm thick polyethylene terephthalate (PET) film was subjected to corona treatment and used as a base material.
Apply an ethyl acetate solution of adhesive (1) with a doctor knife so that the thickness of the dry film is about 30 μm on the surface of the substrate that has been subjected to corona treatment, and heat at 110 ° C. for 5 minutes. The working solution was dried. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, the surface of the pressure-sensitive adhesive (1) layer was covered with a PET film subjected to a release treatment.

Apply an ethyl acetate solution of adhesive (2) with a doctor knife on a PET film with a release treatment on the surface so that the dry film thickness is about 30 μm, and heat at 110 ° C. for 5 minutes. The solvent was evaporated and the coating solution was dried. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state.
Next, a PET film having a release treatment applied to the surface of the pressure-sensitive adhesive (2) layer was attached. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

Next, one of the PET films that have been subjected to the release treatment applied to both sides of the pressure-sensitive adhesive (2) layer is peeled off, and the pressure-sensitive adhesive (2) layer side is provided with the pressure-sensitive adhesive (1) layer. The pressure-sensitive adhesive (1) was bonded to the surface having no layer. Thereby, the adhesive layer was provided on both surfaces, and the double-sided adhesive tape by which the surface was protected by the PET film by which the mold release process was performed was obtained. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

<Manufacture of IC chips>
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was supported by the base material. The obtained structure was hard to break and excellent in handleability.

(Example 2)
A corona treatment was applied to one surface of a polyethylene terephthalate (PET) film having a thickness of 50 μm, and a mold release treatment was applied to the other surface, which was used as a base material.
The ethyl acetate solution of the pressure-sensitive adhesive (1) prepared in Example 1 was applied to the surface of the substrate on the side subjected to corona treatment with a doctor knife so that the thickness of the dry film was about 30 μm, and 110 ° C. The coating solution was dried by heating for 5 minutes. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Then
The surface of the pressure-sensitive adhesive (1) layer was covered with a PET film subjected to a release treatment.

PET whose surface was subjected to a release treatment from the ethyl acetate solution of the pressure-sensitive adhesive (2) prepared in Example 1
The film is coated on the film with a doctor knife so that the dry film thickness is about 30 μm.
The coating solution was dried by heating at 5 ° C. for 5 minutes to evaporate the solvent. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, a PET film having a release treatment applied to the surface of the pressure-sensitive adhesive (2) layer was attached. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

Next, one of the PET films that have been subjected to the release treatment applied to both sides of the pressure-sensitive adhesive (2) layer is peeled off, and the pressure-sensitive adhesive (2) layer side is provided with the pressure-sensitive adhesive (1) layer. It was bonded to the surface that was subjected to the mold release treatment. Thereby, the adhesive layer was provided on both surfaces, and the double-sided adhesive tape by which the surface was protected by the PET film by which the mold release process was performed was obtained. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

<Manufacture of IC chips>
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was supported by the base material. The obtained structure was hard to break and excellent in handleability.

(Example 3)
An IC chip was manufactured using the double-sided adhesive tape prepared in Example 2.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was supported by the base material. The obtained structure was hard to break and excellent in handleability.

Example 4
<Production of double-sided adhesive tape>
By containing carbon black, one surface of an opaque polyethylene terephthalate (PET) film having a thickness of 50 μm was subjected to corona treatment, and this was used as a base material.
The ethyl acetate solution of the pressure-sensitive adhesive (2) prepared in Example 2 was applied to the surface of the substrate on the side subjected to corona treatment with a doctor knife so that the thickness of the dry film was about 30 μm, and 110 ° C. The coating solution was dried by heating for 5 minutes. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Then
The surface of the pressure-sensitive adhesive (2) layer was covered with a PET film subjected to a release treatment.

Apply an ethyl acetate solution of adhesive (2) with a doctor knife on a PET film with a release treatment on the surface so that the dry film thickness is about 30 μm, and heat at 110 ° C. for 5 minutes. The solvent was evaporated and the coating solution was dried. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state.
Next, a PET film having a release treatment applied to the surface of the pressure-sensitive adhesive (2) layer was attached. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

Next, one of the PET films that have been subjected to the release treatment applied to both sides of the pressure-sensitive adhesive (2) layer is peeled off, and the pressure-sensitive adhesive (2) layer side is provided with the pressure-sensitive adhesive (2) layer. The pressure-sensitive adhesive (2) was bonded to the surface having no layer. Thereby, the adhesive layer was provided on both surfaces, and the double-sided adhesive tape by which the surface was protected by the PET film by which the mold release process was performed was obtained. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

<Manufacture of IC chips>
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (4) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was supported by the base material. The obtained structure was hard to break and excellent in handleability.

(Example 5)
An IC chip was produced using the double-sided pressure-sensitive adhesive tape produced in Example 1.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.
(Dicing tape application process)
The silicon wafer was removed from the grinding apparatus, and a dicing tape was stuck on the silicon wafer.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the dicing tape side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to be 0 mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was sandwiched between the dicing tape and the base material.
(Substrate peeling process)
With a silicon wafer fixed by vacuum suction from the dicing tape side, using a super high pressure mercury lamp from the substrate side, the irradiation intensity of the ultraviolet light of 365 nm to the glass plate surface is 40 m.
After adjusting the illuminance to W / cm ² and irradiating for 2 minutes, the adhesive (1) layer was cured to reduce the adhesive strength, and then peeled off while turning the substrate from the surface of the silicon wafer.
(Dicing process)
Subsequently, in a normal pressure environment, the silicon wafer reinforced with the dicing tape was attached to a dicing apparatus, a cutter blade was cut from the wafer side, and the silicon wafer was cut into the size of an IC chip. Next, the dicing tape was peeled off to obtain an IC chip.

(Example 6)
An IC chip was manufactured using the double-sided adhesive tape prepared in Example 2.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.
(Dicing tape application process)
The silicon wafer was removed from the grinding apparatus, and a dicing tape was stuck on the silicon wafer.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the dicing tape side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to be 0 mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was sandwiched between the dicing tape and the base material.
(Substrate peeling process)
With a silicon wafer fixed by vacuum suction from the dicing tape side, using a super high pressure mercury lamp from the substrate side, the irradiation intensity of the ultraviolet light of 365 nm to the glass plate surface is 40 m.
After adjusting the illuminance to W / cm ² and irradiating for 2 minutes, the adhesive (1) layer was cured to reduce the adhesive strength, and then peeled off while turning the substrate from the surface of the silicon wafer.
(Dicing process)
Subsequently, in a normal pressure environment, the silicon wafer reinforced with the dicing tape was attached to a dicing apparatus, a cutter blade was cut from the wafer side, and the silicon wafer was cut into the size of an IC chip. Next, the dicing tape was peeled off to obtain an IC chip.

(Example 7)
An IC chip was manufactured using the double-sided adhesive tape prepared in Example 2.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.
(Dicing tape application process)
The silicon wafer was removed from the grinding apparatus, and a dicing tape was stuck on the silicon wafer.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the dicing tape side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to be 0 mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was sandwiched between the dicing tape and the base material.
(Substrate peeling process)
With a silicon wafer fixed by vacuum suction from the dicing tape side, using a super high pressure mercury lamp from the substrate side, the irradiation intensity of the ultraviolet light of 365 nm to the glass plate surface is 40 m.
After adjusting the illuminance to W / cm ² and irradiating for 2 minutes, the adhesive (1) layer was cured to reduce the adhesive strength, and then peeled off while turning the substrate from the surface of the silicon wafer.
(Dicing process)
Subsequently, in a normal pressure environment, the silicon wafer reinforced with the dicing tape was attached to a dicing apparatus, a cutter blade was cut from the wafer side, and the silicon wafer was cut into the size of an IC chip. Next, the dicing tape was peeled off to obtain an IC chip.

(Example 8)
An IC chip was manufactured using the double-sided adhesive tape prepared in Example 4.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (4) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.
(Dicing tape application process)
The silicon wafer was removed from the grinding apparatus, and a dicing tape was stuck on the silicon wafer.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the dicing tape side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to be 0 mW / cm ² . This allowed the glass plate to be separated from the wafer together with the adhesive (2) layer (ie, peeling occurred at interface B in FIG. 1b). No adhesive residue of the adhesive (2) was observed on the surface of the substrate.
Thereafter, the vacuum was released to obtain a structure in which the silicon wafer was sandwiched between the dicing tape and the base material.
(Substrate peeling process)
After the structure in which the obtained silicon wafer is sandwiched between the dicing tape and the substrate is heated on a hot plate to generate gas from the gas generating agent contained in the pressure-sensitive adhesive (2) layer to reduce the adhesive force In a state where the silicon wafer was fixed by vacuum suction from the dicing tape side, the substrate was peeled off while turning the substrate from the surface of the silicon wafer.
(Dicing process)
Subsequently, in a normal pressure environment, the silicon wafer reinforced with the dicing tape was attached to a dicing apparatus, a cutter blade was cut from the wafer side, and the silicon wafer was cut into the size of an IC chip. Next, the dicing tape was peeled off to obtain an IC chip.

(Comparative Example 1)
<Production of double-sided adhesive tape>
A polyethylene terephthalate (PET) film having a thickness of 50 μm was used as a base material.
The ethyl acetate solution of the pressure-sensitive adhesive (1) prepared in Example 1 was applied to one side of the substrate with a doctor knife so that the thickness of the dry film was about 30 μm, and heated at 110 ° C. for 5 minutes. The coating solution was dried. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, the surface of the pressure-sensitive adhesive (1) layer was covered with a PET film subjected to a release treatment.

PET whose surface was subjected to a release treatment from the ethyl acetate solution of the pressure-sensitive adhesive (2) prepared in Example 1
The film is coated on the film with a doctor knife so that the dry film thickness is about 30 μm.
The coating solution was dried by heating at 5 ° C. for 5 minutes to evaporate the solvent. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, a PET film having a release treatment applied to the surface of the pressure-sensitive adhesive (2) layer was attached. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

Next, one of the PET films that have been subjected to the release treatment applied to both sides of the pressure-sensitive adhesive (2) layer is peeled off, and the pressure-sensitive adhesive (2) layer side is provided with the pressure-sensitive adhesive (1) layer. The pressure-sensitive adhesive (1) was bonded to the surface having no layer. Thereby, the adhesive layer was provided on both surfaces, and the double-sided adhesive tape by which the surface was protected by the PET film by which the mold release process was performed was obtained. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

<Manufacture of IC chips>
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . As a result, the glass plate is separated from the wafer together with the base material, and only the ground ultra-thin silicon wafer is left (that is,
Peeling occurred at interface D in FIG. 1b). This ultra-thin silicon wafer is very easily damaged, and may be damaged during transfer to the next process.

(Comparative Example 2)
<Production of double-sided adhesive tape>
A mold release treatment was performed on one surface of a 50 μm thick polyethylene terephthalate (PET) film, which was used as a base material.
The ethyl acetate solution of the pressure-sensitive adhesive (1) prepared in Example 1 was applied with a doctor knife so that the thickness of the dry film was about 30 μm on the side of the substrate that had been subjected to the mold release treatment, and 110 ° C. The coating solution was dried by heating for 5 minutes. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, the surface of the pressure-sensitive adhesive (1) layer was covered with a PET film subjected to a release treatment.

PET whose surface was subjected to a release treatment from the ethyl acetate solution of the pressure-sensitive adhesive (2) prepared in Example 1
The film is coated on the film with a doctor knife so that the dry film thickness is about 30 μm.
The coating solution was dried by heating at 5 ° C. for 5 minutes to evaporate the solvent. The pressure-sensitive adhesive layer after drying showed adhesiveness in a dry state. Next, a PET film having a release treatment applied to the surface of the pressure-sensitive adhesive (2) layer was attached. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

Next, one of the PET films that have been subjected to the release treatment applied to both sides of the pressure-sensitive adhesive (2) layer is peeled off, and the pressure-sensitive adhesive (2) layer side is provided with the pressure-sensitive adhesive (1) layer. The pressure-sensitive adhesive (1) was bonded to the surface having no layer. Thereby, the adhesive layer was provided on both surfaces, and the double-sided adhesive tape by which the surface was protected by the PET film by which the mold release process was performed was obtained. Thereafter, the film was allowed to stand at 40 ° C. for 3 days for curing.

<Manufacture of IC chips>
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
The surface of this glass plate was previously treated with a silane coupling agent.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted for 2 minutes while adjusting the illuminance to mW / cm ² . As a result, the glass plate is separated from the wafer together with the base material, and only the ground ultra-thin silicon wafer is left (that is,
Peeling occurred at interface D in FIG. 1b). This ultra-thin silicon wafer is very easily damaged, and may be damaged during transfer to the next process.

(Comparative Example 3)
An IC chip was produced using the double-sided pressure-sensitive adhesive tape produced in Example 1.
(Lamination of silicon wafer and glass plate)
The PET film protecting the pressure-sensitive adhesive (1) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. Next, the PET film protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape was peeled off and attached to a glass plate having a diameter of 20.4 cm using a vacuum bonding machine.
(Grinding process)
A silicon wafer reinforced with a glass plate was attached to a grinding apparatus and ground until the thickness of the silicon wafer reached about 30 μm.

(UV irradiation process)
In a state where the silicon wafer is fixed by vacuum suction from the silicon wafer side, an ultraviolet ray of 365 nm is irradiated from the glass plate side to the surface of the glass plate using an ultrahigh pressure mercury lamp.
Irradiation was adjusted to mW / cm ² for 2 minutes. As a result, the glass plate could be separated from the wafer, but most of the adhesive (2) remained on the surface of the base material (that is, peeling occurred at the interface A in FIG. 1b). . This structure was inferior in subsequent handling properties because the adhesive (2) remained on the surface of the substrate.

According to the present invention, there is provided an IC chip manufacturing method capable of preventing breakage of a wafer, improving handling, and processing into an IC chip with high productivity even for a very thin wafer having a thickness of 50 μm or less. it can.

It is a mimetic diagram explaining one embodiment of a manufacturing method of an IC chip of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wafer 2 Support plate 3 Double-sided adhesive tape 31 Base material 321 Adhesive layer (support plate side)
322 Adhesive layer (wafer, IC chip side)
4 Dicing tape

Claims (5)

Fixing the wafer to the support plate via a double-sided pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer containing a gas generating agent that generates gas by stimulation is formed on at least one surface of the substrate;
A step 2 of grinding the wafer while being fixed to the support plate via the double-sided adhesive tape;
A method for producing an IC chip, which includes a step 3 for separating the support plate and the wafer by giving a stimulus and separating the support plate and the wafer by separating the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape,
In the step 1, an adhesive layer containing a gas generating agent that generates gas by stimulation of the double-sided adhesive tape and the support plate are bonded together. In step 1, when the double-sided pressure-sensitive adhesive tape is released and the wafer is fixed to the support plate, the adhesive strength at the interface between the support plate and the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape is 2. The method of manufacturing an IC chip according to claim 1, wherein the adhesive strength is higher than the adhesive strength at the interface between the pressure-sensitive adhesive layer on the support plate side and the substrate. In step 3, the adhesive strength at the interface between the support plate immediately before giving a stimulus and the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape is determined by the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape and the substrate. 3. The method of manufacturing an IC chip according to claim 1, wherein the adhesive strength is higher than that at the interface. In step 3, the adhesive strength at the interface between the support plate and the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape when separating the support plate and the wafer is the pressure-sensitive adhesive layer on the support plate side of the double-sided pressure-sensitive adhesive tape 4. The method of manufacturing an IC chip according to claim 1, wherein the adhesive strength is higher than an adhesive strength at an interface between the substrate and the substrate. The surface of the support plate is subjected to an adhesion improving treatment and / or the surface of the substrate that is to be bonded to the support plate is subjected to a mold release treatment. 4. A method for producing an IC chip according to 4.

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