JP2004006522A - Method for manufacturing ic chip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an IC chip, which enables an excellent processing into an IC chip by preventing damages or the like on a wafer even when the thickness thereof is so extremely thin as 50μm and by improving its handling properties. <P>SOLUTION: The method for manufacturing an IC chip comprises a process 1 for forming a groove in a wafer along a dicing line, from the side of the surface in which a circuit pattern is formed, so that the depth of the groove becomes larger than the thickness of a completed chip; a process 2 for fixing the wafer to a support plate through a two-sided adhesive tape which comprises at least on one side thereof a gas-generating agent which generates gas with stimulation; a process 3 for polishing the wafer which is in the state of being fixed to the support plate so that its thickness becomes that of a chip in completion, and dividing the resultant into individual chips; and a process 4 for giving stimulation to the two-sided adhesive tape. In the process 2 wherein the wafer is fixed to the support plate through the two-sided adhesive tape, the side of the tape, which contains the gas-generating agent, and the surface of the wafer, in which the circuit pattern is formed, are stuck together. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of manufacturing an IC chip which can prevent breakage of the wafer even if the thickness is as thin as about 50 μm, improve the handleability, and can process the IC chip satisfactorily.
[0002]
[Prior art]
2. Description of the Related Art A semiconductor integrated circuit (IC chip) is usually formed by slicing a high-purity rod-shaped semiconductor single crystal or the like into a wafer, forming a predetermined circuit pattern on the wafer surface using a photoresist, and then forming a wafer back surface. It is manufactured by polishing with a polishing machine to reduce the thickness of the wafer to about 100 to 600 μm, and finally dicing to make chips.
[0003]
At the time of the above-mentioned polishing, an adhesive sheet (polishing tape) is attached to the wafer surface to prevent the breakage of the wafer or to facilitate the polishing process. (Dicing tape) is attached, and the wafer is diced in a state where the wafer is bonded and fixed. The formed chip is picked up by a needle from the film substrate side of the dicing tape with a needle, and is fixed on the die pad.
[0004]
In recent years, as the use of IC chips has expanded, an extremely thin semiconductor wafer having a thickness of about 50 μm that can be used for IC cards or stacked and used has been required. However, a semiconductor wafer having a thickness of about 50 μm has a larger warp than a conventional semiconductor wafer having a thickness of about 100 to 600 μm and is more likely to be broken by an impact. Then, it may be damaged.
[0005]
A semiconductor wafer having a thickness of about 50 μm has a high risk of being damaged in a polishing process or a dicing process, which is easily affected by an impact, and is also easily damaged when a bump is formed on an electrode of an IC chip. For this reason, it has been an important issue to improve the handleability of a wafer in the process of manufacturing IC chips from a thin semiconductor wafer having a thickness of about 50 μm.
[0006]
[Problems to be solved by the invention]
In view of the above situation, the present invention provides a method of manufacturing an IC chip that can prevent breakage of a wafer even with an extremely thin wafer having a thickness of about 50 μm, improve handleability, and can process the IC chip satisfactorily. The purpose is to provide.
[0007]
[Means for Solving the Problems]
The present invention provides at least a step 1 of forming a groove deeper than the thickness of a completed chip from the circuit pattern forming surface side along a dicing line of a wafer on which a circuit pattern is formed, and stimulating at least one surface. Step 2 of fixing the wafer to a transparent support plate via a double-sided adhesive tape containing a gas generating agent that generates a gas according to Step 2 in which the wafer is fixed to the support plate and has a thickness of a completed chip. A method of manufacturing an IC chip having a step 3 of polishing and separating the chips into individual chips, and a step 4 of stimulating the double-sided adhesive tape, wherein the wafer is attached to the support plate via the double-sided adhesive tape. In the fixing step 2, manufacture of an IC chip in which the surface of the double-sided pressure-sensitive adhesive tape containing the gas generating agent is bonded to the surface of the wafer on which the circuit pattern is formed. It is the law.
Hereinafter, the present invention will be described in detail.
[0008]
In step 1 of the method of manufacturing an IC chip according to the present invention, a groove is formed along a dicing line of a wafer on which a circuit pattern has been formed, from the surface on which the circuit pattern is formed, to a groove deeper than the thickness of the completed chip.
The wafer is a semiconductor wafer obtained by slicing a high-purity silicon single crystal, gallium arsenide single crystal, or the like, and has a predetermined circuit pattern formed on the wafer surface, and has a thickness of about 500 μm to 1 mm.
[0009]
The method for forming the groove is not particularly limited, for example, a wafer on which a circuit pattern is formed is fixed on a chuck table of a dicing apparatus with the pattern forming surface side up, and cutting water is cut using a dicing blade. There is a method of cutting to a predetermined depth while hanging.
The depth of the groove formed in the wafer is preferably at least 5 μm deeper than the thickness of the completed chip. If the thickness is less than 5 μm, the wafer may not be reliably separated into individual chips even when polished.
[0010]
In step 2 of the method of manufacturing an IC chip according to the present invention, the wafer is fixed to the support plate via a double-sided adhesive tape.
By fixing the wafer to the support plate, the handleability of the wafer is improved, the breakage of the wafer can be prevented even for an extremely thin wafer having a thickness of about 50 μm, and the IC chip can be favorably processed.
[0011]
The support plate is not particularly limited, but is preferably transparent when the stimulus for generating a gas from the gas generating agent described below is light. For example, a glass plate; acryl, olefin, polycarbonate, vinyl chloride , ABS, polyethylene terephthalate (PET), nylon, urethane, a plate made of a resin such as polyimide, and the like.
A preferred lower limit of the thickness of the support plate is 500 μm, a preferred upper limit is 3 mm, a more preferred lower limit is 1 mm, and a more preferred upper limit is 2 mm. It is preferable that the variation in the thickness of the support plate is 1% or less.
[0012]
The double-sided pressure-sensitive adhesive tape contains a gas generating agent that generates a gas upon stimulation on at least one surface.
The double-sided pressure-sensitive adhesive tape may be a tape in which a pressure-sensitive adhesive layer is formed on both sides of a substrate, or may be a tape including only a pressure-sensitive adhesive layer without a substrate.
The substrate is not particularly limited, but when the stimulus for generating gas from the gas generating agent described below is stimulus by light, it is preferable that the stimulus transmits or passes light, for example, acrylic, olefin, Examples include a sheet made of a transparent resin such as polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), nylon, urethane, and polyimide, a sheet having a network structure, and a sheet having holes.
[0013]
Examples of the stimulus for generating a gas from the gas generating agent include light, heat, and ultrasonic stimulation. Among them, stimulation by light or heat is preferred. Examples of the light include ultraviolet light and visible light. When light stimulation is used as the stimulation, the pressure-sensitive adhesive layer containing the gas generating agent is preferably capable of transmitting or passing light.
Although there is no particular limitation on the gas generating agent that generates gas by the above stimulus, for example, azo compounds and azide compounds are preferably used.
[0014]
Examples of the azo compound include 2,2′-azobis- (N-butyl-2-methylpropionamide) and 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 (N-butyl-2-methylpropionamide), 2,2'-azobis (N-cyclohexyl-2-methylpropionamide), 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloro Id, 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane] disulfatedi Hydrorate, 2,2′-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2′-azobis {2- [1- (2- (Hydroxyethyl) -2-imidazoyl-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- Tyl-propionamidyne], 2,2′-azobis {2- [N- (2-carboxyethyl) amidine] propane}, 2,2′-azobis (2-methylpropionamidooxime), dimethyl 2,2 ′ -Azobis (2-methylpropionate), dimethyl 2,2'-azobisisobutyrate, 4,4'-azobis (4-cyancarbonic acid), 4,4'-azobis (4-cyanopentanoic Acid), 2,2′-azobis (2,4,4-trimethylpentane) and the like.
In the production of IC chips, a step of performing high-temperature treatment is included if necessary, and among these, 2,2′-azobis- (N-butyl-2-methylpropionamide), which has a high thermal decomposition temperature, 2,2′-azobis (N-butyl-2-methylpropionamide) and 2,2′-azobis (N-cyclohexyl-2-methylpropionamide) are preferred.
These azo compounds generate nitrogen gas when stimulated by light, heat, or the like.
[0015]
Examples of the azide compound include 3-azidomethyl-3-methyloxetane, terephthalazide, p-tert-butylbenzazide; and glycidyl azide polymer obtained by ring-opening polymerization of 3-azidomethyl-3-methyloxetane. Polymers having an azide group are exemplified.
These azide compounds generate nitrogen gas when stimulated by light, heat, impact or the like.
[0016]
Among these gas generating agents, the azide compound has a problem that it is difficult to handle because it is easily decomposed and gives off nitrogen gas even when subjected to impact. Furthermore, once the decomposition starts, the azide compound causes a chain reaction, explosively releases nitrogen gas, and the control cannot be performed. Therefore, there is a problem that the explosively generated nitrogen gas may damage the wafer. is there. Due to such a problem, the amount of the azide compound used is limited, but the limited amount may not provide a sufficient effect.
On the other hand, the azo compound, unlike the azide compound, does not generate gas by impact, and is therefore extremely easy to handle. In addition, since there is no explosive gas generated due to a chain reaction, the wafer is not damaged, and gas generation can be interrupted by interrupting light irradiation. There is also the advantage that it is possible. Therefore, it is more preferable to use an azo compound as the gas generating agent.
[0017]
By containing the gas generating agent, when a stimulus is given to the double-sided pressure-sensitive adhesive tape, gas is generated from the gas generating agent, and by peeling off at least a part of the adhesive surface, the adhesive force is reduced and the adherend is reduced. It can be easily peeled off.
[0018]
The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer containing the gas generating agent of the double-sided pressure-sensitive adhesive tape preferably has an elastic modulus which is increased by stimulation. The stimulus for increasing the elastic modulus of the pressure-sensitive adhesive may be the same as or different from the stimulus for generating gas from the gas generating agent.
Examples of the pressure-sensitive adhesive include, for example, a polymerizable polymer of an alkyl acrylate type and / or an alkyl methacrylate type having a radical polymerizable unsaturated bond in a molecule, and a radical polymerizable polyfunctional oligomer. Or, a photocurable pressure-sensitive adhesive containing a monomer as a main component and optionally containing a photopolymerization initiator, or an alkyl acrylate having a radical polymerizable unsaturated bond in a molecule and / or Examples thereof include those composed of a thermosetting pressure-sensitive adhesive or the like containing a methacrylic acid alkyl ester-based polymerizable polymer and a radically polymerizable polyfunctional oligomer or monomer as main components and a thermal polymerization initiator.
[0019]
Post-curing pressure-sensitive adhesives such as light-curing pressure-sensitive adhesives or heat-curing pressure-sensitive adhesives are uniformly and quickly polymerized and cross-linked by light irradiation or heating, so that they are integrated. The increase in the elastic modulus due to curing becomes remarkable, and the adhesive strength is greatly reduced. Also, when gas is generated from the gas generating agent in a hard cured product, most of the generated gas is released to the outside, and the released gas peels off at least a part of the adhesive surface of the adhesive from the adherend and adheres Decrease power.
[0020]
As the polymerizable polymer, for example, a (meth) acrylic polymer having a functional group in a molecule (hereinafter referred to as a (meth) acrylic polymer containing a functional group) is synthesized in advance and reacted with the functional group in the molecule. (Hereinafter, referred to as a functional group-containing unsaturated compound) having a functional group and a radical polymerizable unsaturated bond.
[0021]
The functional group-containing (meth) acrylic polymer is a polymer having tackiness at room temperature, and is an acryl polymer having an alkyl group having a carbon number of usually 2 to 18 as in a general (meth) acrylic polymer. An acid alkyl ester and / or a methacrylic acid alkyl ester as a main monomer, and a functional group-containing monomer and, if necessary, another copolymerizable monomer copolymerizable therewith by a conventional method. It is obtained. The weight average molecular weight of the functional group-containing (meth) acrylic polymer is usually about 200,000 to 2,000,000.
[0022]
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 monomer such as 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.
[0023]
Examples of other copolymerizable modifying monomers include various monomers used in general (meth) acrylic polymers such as vinyl acetate, acrylonitrile, and styrene.
[0024]
As the functional group-containing unsaturated compound to be reacted with the functional group-containing (meth) acrylic polymer, the same compound as the functional group-containing monomer described above according to the functional group of the functional group-containing (meth) acrylic polymer is used. 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. When the functional group is an amino group, an epoxy group-containing monomer is used.
[0025]
The polyfunctional oligomer or monomer preferably has a molecular weight of 10,000 or less, and more preferably has a molecular weight of 5, so that the three-dimensional network of the pressure-sensitive adhesive layer can be efficiently formed by heating or irradiation with light. 000 or less and the number of radically polymerizable unsaturated bonds in the molecule is 2 to 20. Such more preferred polyfunctional oligomers or monomers include, for example, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate Alternatively, methacrylates similar to the above may be used. Other examples include 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylates, and methacrylates similar to those described above. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.
[0026]
Examples of the photopolymerization initiator include those activated by irradiation with light having a wavelength of 250 to 800 nm. Examples of such photopolymerization initiators 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 and Michler's ketone , Chlorothioxanthone, todecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexylphenylketone, 2-hydroxymethylphenylpro Examples include a photo-radical polymerization initiator such as bread. These photopolymerization initiators may be used alone or in combination of two or more.
[0027]
Examples of the thermal polymerization initiator include those which generate an active radical which is decomposed by heat to initiate polymerization curing. Specific examples thereof include dicumyl peroxide, di-t-butyl peroxide, and t-butyl. Examples include peroxybenzoyl, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide, di-t-butyl peroxide and the like. Among them, cumene hydroperoxide, paramenthane hydroperoxide, di-t-butyl peroxide, and the like are preferable because of high thermal decomposition temperature. Among these thermal polymerization initiators, commercially available ones are not particularly limited, but, for example, perbutyl D, perbutyl H, perbutyl P, permentor H (all of these are manufactured by NOF Corporation) and the like are preferable. These thermal polymerization initiators may be used alone or in combination of two or more.
[0028]
In the post-curing pressure-sensitive adhesive, in addition to the above components, for the purpose of adjusting the cohesive force as a pressure-sensitive adhesive, isocyanate compounds, melamine compounds, various kinds of compounds that are blended into a general pressure-sensitive adhesive such as an epoxy compound, if desired. A polyfunctional compound may be appropriately blended. Known additives such as a plasticizer, a resin, a surfactant, a wax, and a fine particle filler can also be added.
[0029]
In step 2 of the method for manufacturing an IC chip according to the present invention, the surface of the double-sided pressure-sensitive adhesive tape containing the gas generating agent may be bonded to the surface of the wafer on which the circuit pattern is formed, or the double-sided pressure-sensitive adhesive tape may be bonded. The surface containing the gas generating agent may be bonded to the support plate. By bonding the wafer and the support plate using the double-sided pressure-sensitive adhesive tape, even if the wafer is polished to a thickness of 50 μm or less, the chips will not be damaged and the chips can be handled very easily. Furthermore, after a series of processing is completed, gas is generated from the contained gas generating agent by stimulating the pressure-sensitive adhesive layer, and the generated gas is released to the bonding surface between the chip or the support plate and the double-sided pressure-sensitive adhesive tape. Then, at least a part of the adhesive surface of the pressure-sensitive adhesive is peeled off from the chip or the support plate to reduce the adhesive strength, and the chip can be easily peeled. When the surface of the double-sided pressure-sensitive adhesive tape containing the gas generating agent is bonded to the support plate, a stimulus is applied between the support and the double-sided pressure-sensitive adhesive tape prior to peeling the double-sided pressure-sensitive adhesive tape from the chip. By generating gas from the gas generating agent to reduce the adhesive strength and peeling the hard support plate from the double-sided adhesive tape, the double-sided adhesive tape becomes a flexible tape and can be peeled off from the chip while turning over the tape .
[0030]
In step 3 of the method for manufacturing an IC chip according to the present invention, the wafer is separated into individual chips by polishing the wafer to the thickness of the completed chip while fixing the wafer to the support plate. As described above, since grooves are formed in the wafer in advance that are deeper than the thickness of the completed chip, if the wafer is polished to the thickness of the completed chip, the wafer can be separated into individual chips. it can.
The polishing method is not particularly limited, and a method used in a normal IC chip manufacturing method can be used. For example, a polishing whetstone that fixes a wafer supporting plate fixed to a supporting plate and rotates at high speed can be used. And polishing to a predetermined thickness while applying cutting water.
[0031]
In step 4 of the method for manufacturing an IC chip of the present invention, a stimulus for reducing the adhesive strength is applied to the double-sided adhesive tape. The method of applying the stimulus is not particularly limited. For example, when a gas generating agent that generates a gas by stimulating with ultraviolet light is used, a method of irradiating the support plate with ultraviolet light may be used.
The method of irradiating the ultraviolet light is not particularly limited, and the entirety may be simultaneously irradiated with an amount of ultraviolet light that generates gas from the gas generating agent, or may be selectively applied to a chip to be picked up in accordance with a pickup described later. UV light may be applied to the surface. Alternatively, a sufficient amount of ultraviolet rays may be radiated to the entirety of the gas generating agent to generate gas from the gas generating agent, and then the chip to be picked up may be further irradiated with ultraviolet rays to selectively increase the amount of ultraviolet irradiation. . By selectively irradiating ultraviolet rays or selectively increasing the amount of ultraviolet irradiation, it is possible to reduce the adhesive strength of only the chip that is picked up by the gas generated from the gas generating agent, and also generated from the gas generating agent. The gas thus generated is preferable because it generates a force for lifting the chip, so that the pickup becomes easy.
[0032]
Step 4 of the method for manufacturing an IC chip of the present invention may be performed after a dicing tape is attached to the polished surface of the wafer separated into individual chips. Thus, in step 4, the double-sided pressure-sensitive adhesive tape is stimulated to reduce the adhesive strength, and after peeling off the double-sided pressure-sensitive adhesive tape from the wafer, the pick-up of the separated chip is performed by using a needle from the dicing tape side to produce a normal IC chip. It can be done according to the method.
Further, in the method for manufacturing an IC chip of the present invention, the pickup may be performed at the same time as or after Step 4 without sticking to the dicing tape. In the above step 2, when the surface containing the gas generating agent of the double-sided pressure-sensitive adhesive tape is bonded to the wafer, the adhesive force of the double-sided pressure-sensitive adhesive tape is reduced by the stimulation in step 4, and Therefore, the method of peeling the chip from the double-sided adhesive tape is constant, and it is not necessary to finely adjust the stroke of the pickup, and the chip can be picked up very easily with a constant stroke.
The pick-up method is not particularly limited, and examples thereof include a method of selectively picking up a chip using a pickup device capable of picking up a chip by moving a thin tube while bringing the thin tube into contact with the suction. . According to this method, there is less possibility that the chip will be broken than the method of pushing up with a needle.
[0033]
In the method of manufacturing an IC chip according to the present invention, the wafer is bonded to the support plate with the double-sided adhesive tape, and the polishing is performed in this state. Therefore, even when the wafer is extremely thinned to a thickness of about 50 μm, chip breakage or the like may occur. , The handleability is improved, and the IC chip can be favorably processed. Also, grooves are formed in advance on the wafer that are deeper than the thickness of the chips at the time of completion, and the wafers are separated into individual chips by polishing the grooves. An IC chip can be manufactured with higher efficiency as compared with a method of attaching a tape and performing dicing. Further, by giving a stimulus, the adhesive strength of the double-sided adhesive tape is reduced, so that the obtained chip can be picked up very easily.
[0034]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.
[0035]
(Example 1)
<Preparation of adhesive>
On the other hand, the following compound was dissolved in ethyl acetate, and polymerization was carried out by irradiating ultraviolet rays to obtain an acrylic copolymer having a weight average molecular weight of 700,000.
3.5 parts by weight of 2-isocyanatoethyl methacrylate was added to 100 parts by weight of the resin solid content of the ethyl acetate solution containing the obtained acrylic copolymer to cause a reaction, and further, the resin of the ethyl acetate solution after the reaction was added. 40 parts by weight of pentaerythritol triacrylate, 5 parts by weight of a photopolymerization initiator (Irgacure 651) and 0.5 part by weight of polyisocyanate are mixed with 100 parts by weight of the solid content to prepare an ethyl acetate solution of the pressure-sensitive adhesive (1). did.
79 parts by weight of butyl acrylate 15 parts by weight of ethyl acrylate 1 part by weight of acrylic acid 5 parts by weight of 2-hydroxyethyl acrylate 0.2 parts by weight of photopolymerization initiator (Irgacure 651, 50% ethyl acetate solution)
Lauryl mercaptan 0.01 parts by weight
Furthermore, 30 parts by weight of 2,2′-azobis- (N-butyl-2-methylpropionamide) and 2,4- 3.6 parts by weight of diethylthioxanthone was mixed to prepare a pressure-sensitive adhesive (2) containing a gas generating agent.
[0037]
<Preparation of double-sided adhesive tape>
An ethyl acetate solution of the pressure-sensitive adhesive (1) is coated with a doctor knife on one side of a transparent polyethylene terephthalate (PET) film having a thickness of 100 μm and corona-treated on both sides so that the dry film thickness is about 15 μm. Then, the coating solution was dried by heating at 110 ° C. for 5 minutes. The dried pressure-sensitive adhesive layer showed tackiness in a dry state. Then, an embossed PET (Emlet EM38, manufactured by Unitika Ltd., with a spacing of convex portions of 600 μm) having a release treatment applied to the surface of the pressure-sensitive adhesive (1) layer is pressed to form an uneven pattern on the surface of the pressure-sensitive adhesive (1) layer. Formed. Then, it left still at 40 degreeC for 3 days.
[0038]
An ethyl acetate solution of the pressure-sensitive adhesive (2) is applied on a PET film having a surface subjected to a release treatment by a doctor knife so that the thickness of a dried film becomes about 50 μm, and heated at 110 ° C. for 5 minutes. The solvent was volatilized to dry the coating solution. The dried pressure-sensitive adhesive layer showed tackiness in a dry state. Then, it left still at 40 degreeC for 3 days.
Next, the surface of the PET film provided with the pressure-sensitive adhesive (1) layer, which has been subjected to the corona treatment without the pressure-sensitive adhesive (1) layer, and the surface of the pressure-sensitive adhesive (2) layer of the PET film provided with the pressure-sensitive adhesive (2) layer. And pasted together. Thus, a double-sided pressure-sensitive adhesive tape was obtained in which a pressure-sensitive adhesive layer was provided on both sides and the surface of which was protected by a PET film subjected to a release treatment. The pressure-sensitive adhesive layers of the double-sided pressure-sensitive adhesive tape were all transparent.
[0039]
<Manufacture of IC chips>
(Groove forming process)
A silicon wafer having a diameter of 20 cm and a thickness of about 400 μm having a circuit pattern formed on the surface is mounted on a dicing apparatus, and a cutter blade is cut from the circuit pattern side along a dicing line, and the depth of the groove is greater than the thickness of the polished wafer. The groove was formed so as to be deeper.
(Fixing process to support plate)
The PET film for protecting the pressure-sensitive adhesive (2) layer of the double-sided pressure-sensitive adhesive tape cut into a circle having a diameter of 20 cm was peeled off, and attached to the surface of the grooved silicon wafer on the circuit pattern side. Next, the PET film protecting the pressure-sensitive adhesive (1) layer was peeled off, and a glass plate having a diameter of 20.4 cm was attached to the pressure-sensitive adhesive layer. The bonded surface was strongly bonded immediately after bonding.
(Polishing process)
A silicon wafer reinforced with a double-sided adhesive tape was attached to a polishing apparatus, and polished until the thickness of the silicon wafer became about 50 μm. As a result, the wafer was separated into individual chips.
(UV irradiation step)
Ultraviolet light of 365 nm was irradiated from the glass plate side for 2 minutes while adjusting the illuminance so that the irradiation intensity on the surface of the glass plate was 40 mW / cm ² using an ultrahigh pressure mercury lamp.
(Pickup process)
Each chip was selectively picked up using a pickup device capable of picking up the chip by moving the thin tube while bringing the thin tube into contact with the chip and sucking.
[0040]
(Example 2)
The process up to the polishing step was performed in the same manner as in Example 1. After the wafer was separated into individual chips, a dicing tape was attached to the polished surface of the wafer separated into individual chips. (UV irradiation step)
Ultraviolet light of 365 nm was irradiated from the glass plate side for 2 minutes while adjusting the illuminance so that the irradiation intensity on the surface of the glass plate was 40 mW / cm ² using an ultrahigh pressure mercury lamp.
(Step of peeling double-sided adhesive tape)
The edge of the double-sided adhesive tape was grasped and turned, and the double-sided adhesive tape was peeled from the wafer.
(Pickup process)
Each chip was picked up by selectively pushing up the dicing tape from the dicing table side with a needle using a pickup device capable of pushing up the dicing tape with a needle.
[0041]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, even if it is a very thin wafer about 50 micrometers in thickness, the breakage etc. of a wafer can be prevented, the handling property can be improved, and the manufacturing method of an IC chip which can be processed into an IC chip favorably can be provided.

Claims (3)

at least,
Forming a groove along the dicing line of the wafer on which the circuit pattern is formed, from the surface on which the circuit pattern is formed, to a groove deeper than the thickness of the completed chip;
A step 2 of fixing the wafer to a support plate via a double-sided adhesive tape containing a gas generating agent that generates a gas by stimulation on at least one surface,
A step 3 in which the wafer is polished to the thickness of a completed chip while being fixed to the support plate and separated into individual chips; and
A method for producing an IC chip, comprising a step 4 of stimulating the double-sided adhesive tape,
In step 2 of fixing the wafer to the support plate via the double-sided pressure-sensitive adhesive tape, the surface of the double-sided pressure-sensitive adhesive tape containing the gas generating agent and the surface of the wafer on which the circuit pattern is formed are bonded to each other. A method for manufacturing an IC chip. In the step 2 of fixing the wafer to the support plate via a double-sided adhesive tape containing a gas generating agent that generates a gas by stimulation on at least one surface, the surface of the double-sided adhesive tape containing the gas generating agent and the support plate 2. The method for manufacturing an IC chip according to claim 1, wherein 3. The method for manufacturing an IC chip according to claim 1, wherein step 4 of applying a stimulus to the double-sided adhesive tape is performed after attaching a dicing tape to a polished surface of a wafer separated into individual chips.