JP4268411B2 - Semiconductor chip manufacturing method and dicing adhesive tape - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a large number of semiconductor chips by dicing a semiconductor wafer, and more specifically, dicing is performed in a state where the semiconductor wafer is adhered to a dicing adhesive tape, and then the semiconductor chips are taken out. The present invention relates to a semiconductor chip manufacturing method and a dicing adhesive tape.
[0002]
[Prior art]
When manufacturing a semiconductor chip such as an IC or LSI, a semiconductor wafer having a large number of semiconductor chip circuits formed on the surface is prepared. Next, after the back surface of the semiconductor wafer is polished to a predetermined thickness, the semiconductor wafer is attached to a dicing adhesive tape. Next, the semiconductor wafer affixed to the dicing adhesive tape is diced in the vertical and horizontal directions and divided into a large number of semiconductor chips. Thereafter, the semiconductor chip is peeled off from the dicing adhesive tape and taken out.
[0003]
An example of such a semiconductor chip manufacturing method is disclosed in the following document 1, for example. In the manufacturing method described in this prior art, the semiconductor wafer is adhered to the dicing adhesive tape in order to prevent misalignment of the semiconductor wafer during dicing, and the dicing adhesive tape is irradiated with light after dicing. The adhesive force of the pressure-sensitive adhesive layer is lowered, and thereby the semiconductor chip is easily peeled off from the dicing pressure-sensitive adhesive tape.
[0004]
[Patent Document 1]
JP 7-78793 A
[0005]
[Problems to be solved by the invention]
By the way, when a semiconductor wafer is affixed to the dicing adhesive tape and dicing is performed, it is necessary that the adhesive strength of the dicing adhesive tape is high to some extent. If the adhesive force is not sufficiently high, the position of the semiconductor wafer is displaced during dicing, and the semiconductor wafer cannot be diced with high accuracy.
[0006]
However, in the method described in the above prior art using an adhesive whose adhesive strength is reduced by light irradiation, when the adhesive strength is increased, the adhesive strength may not be sufficiently reduced even when light is irradiated after dicing. there were. Therefore, when the semiconductor chip is peeled off from the dicing adhesive tape using a push-up pin or a suction pad and taken out, the semiconductor chip may be cracked or chipped.
[0007]
Therefore, conventionally, although the adhesive strength of the dicing adhesive tape to the semiconductor wafer during dicing is preferably higher, it has been about 40 to 50 g / 10 mm. This is because when the adhesive strength is higher than this, the adhesive strength after light irradiation is not sufficiently lowered.
[0008]
The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, to prevent the position of the semiconductor wafer from being displaced during dicing, and to sufficiently reduce the adhesive force by the dicing adhesive tape when taking out the semiconductor chip after dicing. Accordingly, it is an object of the present invention to provide a method for manufacturing a semiconductor chip in which cracking and chipping of the semiconductor chip hardly occur, and a dicing adhesive tape used in the manufacturing method.
[0009]
[Means for Solving the Problems]
1st invention of this application is the method of manufacturing many semiconductor chips from a semiconductor wafer, Comprising: The process of preparing a semiconductor wafer, The process of sticking the adhesive tape for dicing on the said semiconductor wafer, It is for this dicing. In the portion where one semiconductor chip obtained by dicing the semiconductor wafer is attached to the adhesive tape, the first region having a relatively high adhesive force and the remaining region, the adhesive force being relatively A step of dicing a semiconductor wafer having a weak or non-adhesive second region and affixed to the dicing adhesive tape and dividing the semiconductor wafer into individual semiconductor chips; and dicing the semiconductor chip into the dicing adhesive And a step of peeling from the tape.
[0010]
On the specific situation with the manufacturing method of the semiconductor chip of this invention, the said 1st area | region is comprised with the adhesive in which adhesive force falls by irritation | stimulation. Therefore, by applying a stimulus such as light or heat, the adhesive strength in the first region is reduced, and the semiconductor chip can be more easily peeled off from the dicing adhesive tape.
[0011]
In another specific aspect of the method for manufacturing a semiconductor chip according to the present invention, the pressure-sensitive adhesive constituting the first region includes a gas generating agent that generates gas by stimulation. In this case, when a stimulus such as light or heat is applied, the gas generating agent generates gas, and therefore gas exists at the interface between the semiconductor chip and the first region of the adhesive tape for dicing. As a result, the semiconductor chip can be more easily separated from the dicing adhesive tape.
[0012]
In a more limited aspect of the method for manufacturing a semiconductor chip according to the present invention, light is used as the stimulus, and therefore, the adhesive force to the semiconductor chip in the first region of the dicing adhesive tape is easily reduced by light irradiation. be able to.
[0013]
In still another specific aspect of the method for manufacturing a semiconductor chip according to the present invention, the adhesive strength of the adhesive in the first region before dicing is 100 g / 10 mm or more at 180 ° peeling adhesive strength to the semiconductor wafer, and therefore The semiconductor wafer is less likely to be displaced during dicing.
[0014]
The pressure-sensitive adhesive tape for dicing according to the present invention is a pressure-sensitive adhesive tape for dicing that is affixed to a semiconductor wafer, and after the semiconductor wafer is divided into individual semiconductor chips by dicing, each semiconductor chip is peeled off. One portion to be affixed has a first region having a relatively high adhesive force and a remaining region that has a relatively weak adhesive force or a second region having no adhesive force. It is characterized by.
[0015]
On the specific situation with the adhesive tape for dicing which concerns on this invention, the said 1st area | region is comprised with the adhesive in which adhesive force falls by irritation | stimulation. Therefore, the adhesion to the semiconductor chip in the first region can be effectively reduced by applying a stimulus such as light or heat.
[0016]
In still another specific aspect of the pressure-sensitive adhesive tape for dicing according to the present invention, the pressure-sensitive adhesive constituting the first region includes a gas generating agent that generates gas by stimulation. In this case, the gas moves to the interface between the semiconductor chip and the first region, whereby the semiconductor chip can be more easily separated from the dicing adhesive tape.
[0017]
When light is used as the stimulus, the adhesive strength to the first region of the dicing adhesive tape of the semiconductor chip can be easily reduced by simply irradiating the light.
When the 180 ° peel adhesion to the semiconductor wafer in the first region is 100 g / 10 mm or more, the semiconductor wafer is securely adhered and fixed to the dicing adhesive tape. Can be suppressed.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention.
[0019]
In the present invention, the semiconductor wafer 1 shown in FIG. 3 is used. In the semiconductor wafer 1, circuits for configuring individual semiconductor chips are formed on the surface 1 a in each region partitioned by streets. In addition, it points out that illustration of a specific circuit is abbreviate | omitted in Fig.3 (a).
[0020]
The semiconductor wafer 1 has a substantially disk shape. In the semiconductor wafer 1, after the circuit is configured on the front surface 1 a, the back surface 1 b side is polished so that the semiconductor wafer 1 has a predetermined thickness.
[0021]
In the present embodiment, the semiconductor wafer 1 having a predetermined thickness is prepared first. The semiconductor wafer is made of, for example, a semiconductor material such as silicon, and the thickness is usually about several hundred μm after being polished. Next, as shown in FIG. 3, a dicing adhesive tape 2 is attached to the back surface 1b of the semiconductor wafer.
[0022]
FIG. 1A is a schematic plan view showing the surface of the dicing adhesive tape 2. The dicing pressure-sensitive adhesive tape 2 is configured by forming a pressure-sensitive adhesive layer on a base material.
[0023]
The substrate is not particularly limited. For example, a synthetic resin film such as polyethylene terephthalate or polypropylene is preferably used. In particular, when the stimulus described below is light, a translucent resin film is preferable as the substrate. Used.
[0024]
In the pressure-sensitive adhesive layer 3 formed on the upper surface of the base material, a first portion having a relatively high adhesive strength in each portion to which one semiconductor chip obtained by dicing the semiconductor wafer 1 at a later stage is attached. The region 3 </ b> A and the remaining second region 3 </ b> B having relatively weak adhesive force or no adhesive force are configured. In FIG. 1B, as shown in an enlarged schematic plan view of a portion to which one semiconductor chip is attached, a substantially circular first region at the center in the portion 3 to which one semiconductor chip is attached. 3A is formed, and a second region 3B is formed therearound.
[0025]
The planar shape of the first region is not limited to a circle, but may be various shapes such as a rectangle and a cross, and the planar shape of the first region as long as the first region 3A is formed in a partial region of the portion 3. Is not particularly limited.
[0026]
In the present embodiment, in the adhesive tape 2 for dicing, the adhesive strength of the first region 3A is relatively higher than that of the second region 3B. The adhesive strength 3A of the first region 3A is desirably high so as not to cause misalignment of the semiconductor wafer 1 during dicing, and is preferably 100 g / mm or more with a 180 ° peeling adhesive strength to the semiconductor wafer. When the peel adhesive strength is 100 g / mm or more, the semiconductor wafer 1 is hardly displaced during dicing, and the semiconductor wafer 1 can be diced with high accuracy.
[0027]
In the present embodiment, the pressure-sensitive adhesive constituting the first region 3A is configured such that the adhesive strength is reduced by light irradiation. Therefore, by irradiating light after dicing, the adhesive strength of the adhesive constituting the first region 3A is reduced, and on the other hand, the adhesive strength of the second region is relatively low. Can be easily peeled from the adhesive tape 2 for dicing.
[0028]
An example of a method for forming the first region 3A and the second region 3B in the dicing adhesive tape 2 will be described with reference to FIG.
As shown in FIG. 2A, an adhesive layer 5 made of an adhesive whose adhesive strength is reduced by light irradiation is formed on the entire surface of the substrate 4. Thereafter, as shown in FIG. 2B, a mask 6 having an opening 6a is placed on the pressure-sensitive adhesive layer 5, and light is irradiated from the mask 6 side as indicated by an arrow A. The opening 6a of the mask 6 is a portion corresponding to the second region 3B shown in FIG. 1B, and the portion corresponding to the first region 3A is configured so that light is not pasted by the mask member 6. Yes. Accordingly, in the pressure-sensitive adhesive layer 5, the first region 3 </ b> A is not irradiated with light by the light irradiation, so that the adhesive force does not decrease, and the light irradiation in the second region 3 </ b> B decreases. In this way, the first and second regions 3A and 3B can be formed. Note that X1 and X1 in FIG. 2B and later-described FIG. 4A indicate cutting positions when the semiconductor wafer is finally diced. That is, the portion 3 between X1 and X1 is a portion 3 attached to one semiconductor chip.
[0029]
As the pressure-sensitive adhesive whose adhesive strength is reduced by the light irradiation, various pressure-sensitive adhesives whose elastic modulus increases by light irradiation can be used. Examples of the pressure-sensitive adhesive include 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 oligomer. Or the photocurable adhesive which has a monomer as a main component and contains a photoinitiator as needed is mentioned.
[0030]
Such photo-curing pressure-sensitive adhesive is uniformly and quickly polymerized and cross-linked by light irradiation, so that the elastic modulus increases significantly due to polymerization and curing, and the adhesive strength is greatly reduced. To do. Accordingly, the adhesive strength of the second region 3B is greatly reduced as compared with the first region 3A.
[0031]
The polymerizable polymer is prepared by, for example, previously synthesizing a (meth) acrylic polymer having a functional group in the molecule (hereinafter referred to as a functional group-containing (meth) acrylic polymer) and reacting with the functional group in the molecule. It can obtain by making it react with the compound (henceforth a functional group containing unsaturated compound) which has a functional group to perform and a radically polymerizable unsaturated bond. In this specification, (meth) acryl means acryl or methacryl.
[0032]
The functional group-containing (meth) acrylic polymer is an acrylic having an alkyl group usually in the range of 2 to 18 as a polymer having adhesiveness at room temperature, as in the case of a general (meth) acrylic polymer. An acid alkyl ester and / or a methacrylic acid alkyl ester as a main monomer, and by copolymerizing it with a functional group-containing monomer and, if necessary, other modifying monomers copolymerizable therewith It is obtained. The weight average molecular weight of the functional group-containing (meth) acrylic polymer is usually about 200 to 2,000,000.
[0033]
Examples of functional group-containing monomers include carboxyl group-containing monomers such as acrylic acid and methacrylic acid; hydroxyl group-containing monomers such as hydroxyethyl acrylate and hydroxyethyl methacrylate; epoxy group-containing monomers such as glycidyl acrylate and glycidyl methacrylate. Isocyanate group-containing monomers such as isocyanate ethyl acrylate and isocyanate ethyl methacrylate; amino group-containing monomers such as aminoethyl acrylate and aminoethyl methacrylate;
[0034]
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.
[0035]
As the functional group-containing unsaturated compound to be reacted with the functional group-containing (meth) acrylic polymer, the same functional group-containing monomer as described above can be used according to the functional group of the functional group-containing (meth) acrylic polymer. 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.
[0036]
The polyfunctional oligomer or monomer preferably has a molecular weight of 10,000 or less, and more preferably has a molecular weight of 5000 or less so that the three-dimensional network of the pressure-sensitive adhesive layer can be efficiently formed by heating or light irradiation. And the lower limit of the number of radically polymerizable unsaturated bonds in the molecule is 2 and the upper limit is 20. Examples of such more preferred polyfunctional oligomers or monomers include trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate. 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate or the same methacrylates as mentioned above. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.
[0037]
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 benzoinpropyl ether and benzoin isobutyl ether; ketal derivative compounds such as benzyldimethyl ketal and acetophenone diethyl ketal; phosphine oxide derivative compounds; bis (η5-cyclopentadienyl) titanocene derivative compounds; Benzophenone, Michler's ketone, chlorothioxanthone, todecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenyl pro Examples thereof include photo radical polymerization initiators such as bread. These photoinitiators may be used independently and 2 or more types may be used together.
[0038]
In addition to the above-mentioned components, the curable pressure-sensitive adhesive has various types that are blended in 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 functional compound suitably. Moreover, you may mix | blend well-known additives, such as plasticity, resin, surfactant, wax, and a fine particle filler.
[0039]
Preferably, the pressure-sensitive adhesive that constitutes the pressure-sensitive adhesive layer 5 contains a gas generating agent that generates a gas upon irradiation with light. In this case, when the semiconductor chip is peeled from the dicing adhesive tape 2 after dicing as will be described later, the adhesive force of the first region 3A itself is reduced by irradiating the first region 3A with light. At the same time, the generated gas moves to the interface between the semiconductor chip and the first region 3A, the adhesive force is further reduced, and the semiconductor chip can be peeled off from the region 3A of the adhesive tape for dicing without difficulty.
[0040]
Although it does not specifically limit as said gas generating agent, For example, an azo compound and an azide compound are used suitably. Examples of the azo compound include 2,2′-azobis- (N-butyl-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 (N-butyl-2-methylpropionamide), 2 , 2'-azobis (N-cyclohexyl-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 di Hydrolate, 2,2'-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- [1- (2- Hydroxyethyl) -2imidazolidin-2-yl] propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane], 2,2'-azobis (2-methylpropionamida) In) Hydrochloride, 2,2'-azobis (2-aminopropane) dihydrochloride, 2,2'-azobis [N- (2-carboxyacyl)- -Methyl-propionamidine, 2,2'-azobis [2- [N- (2-carboxyethyl) amidyne] propane], 2,2'-azobis (2-methylpropionamidoxime), 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.
[0041]
These azo compounds generate nitrogen gas when stimulated by light, heat, or the like.
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 when stimulated by light, heat, impact, or the like.
[0042]
Among the gas generating agents, the azide compound is easily decomposed by releasing an impact and releases nitrogen gas. Therefore, there is a difficulty that handling is difficult. Furthermore, the azide compound undergoes a chain reaction once decomposition starts, explosively releasing nitrogen gas, and its control is not easy. Therefore, the semiconductor wafer may be damaged by the nitrogen gas generated explosively. Therefore, when using an azide compound, it is desirable to reduce the amount of use.
[0043]
On the other hand, unlike an azide compound, an azo compound does not generate gas by impact. Therefore, handling is very easy. In addition, the azo compound does not generate a gas explosively by causing a chain reaction. Therefore, the semiconductor wafer is hardly damaged. In addition, when light irradiation is interrupted, gas generation may be interrupted. Therefore, when an azo compound is used, the adhesiveness can be easily controlled according to the application. Therefore, it is preferable to use an azo compound as the gas generating agent.
[0044]
When the pressure-sensitive adhesive layer 5 is composed of a pressure-sensitive adhesive containing the gas generating agent, as shown in FIG. 2B, when the light is irradiated in the direction of arrow A, the second region 3B is formed. Gas is generated in the constituting adhesive layer portion, but this gas moves to the surface of the second region 3B and scatters. On the other hand, since light is not irradiated in the first region 3A, there is no possibility that the adhesive force of the adhesive in the first region 3A is reduced before dicing.
[0045]
The gas generating agent is desirably contained in a proportion of 5 to 50 parts by weight per 100 parts by weight of the adhesive. When the amount is less than 5 parts by weight, the amount of gas generated is insufficient, and the desired peelability may not be obtained.
[0046]
Moreover, when it exceeds 50 weight part, solubility may deteriorate and malfunctions, such as a bleed, may generate | occur | produce.
In addition, although a gas generating agent is disperse | distributed to the adhesive layer 5, in that case, the adhesive layer 5 whole becomes a foam and there exists a possibility that it may become too soft. Therefore, preferably, at least in the first region 3A, it is desirable that the gas generating agent is unevenly distributed in the surface layer portion adhered to the semiconductor wafer, that is, the portion having a thickness of about 1 to 20 μm from the surface, and more desirably. It is preferable that the gas generating agent is contained only in the portion bonded to the semiconductor wafer.
[0047]
When the gas generating agent is unevenly distributed on the surface layer portion that is adhered to the semiconductor wafer of the adhesive that constitutes at least the first region 3A, when light is irradiated after dicing, the gas generated from the gas generating agent is The transition to the adhesive interface between the adhesive in the first region 3A and the semiconductor chip is surely made. Therefore, the adhesive area between the two is reduced, and the gas acts to peel the semiconductor chip from the adhesive surface in the first region 3A, thereby the adhesive constituting the semiconductor chip and the first region 3A. The adhesive strength of the abruptly decreases.
[0048]
In addition, the aspect which made the surface layer part contain the gas generating agent is an aspect in which the gas generating agent uniformly adheres to the surface of the adhesive, or the gas generating agent attached to the surface of the adhesive is compatible with the adhesive. It also includes an embodiment that is dissolved and absorbed by the adhesive.
[0049]
Examples of the method of containing the gas generating agent only in the surface layer portion include, for example, a method of applying an adhesive containing the gas generating agent with a thickness of about 1 to 20 μm on the pressure sensitive adhesive layer, or a pressure sensitive adhesive layer prepared in advance. Examples thereof include a method of forming a volatile liquid impermeable film containing a gas generating agent on the surface by coating or spraying.
[0050]
The thickness of the surface layer portion varies depending on the thickness of the entire pressure-sensitive adhesive layer, but is preferably a depth portion from the surface of the pressure-sensitive adhesive to 20 μm, and the gas generating agent per 100 parts by weight of the pressure-sensitive adhesive in the surface portion. Is preferably contained in a proportion of 5 to 50 parts by weight.
[0051]
In addition, when making a gas generating agent adhere to the surface of the adhesive layer 5, it is preferable to make the gas generating agent excellent in compatibility with an adhesive adhere. That is, if a large amount of the gas generating agent is attached to the surface of the pressure-sensitive adhesive, the adhesive strength is lowered. The gas can be generated more uniformly over the entire contact surface with the adherend due to the diffusion of the gas generating agent. Further, the surface portion containing the gas generating agent and the others are preferably made of resin components having different compositions, and more preferably made of resin components having different polarities. Thereby, it can prevent that the gas generating agent of a surface part transfers to other than that, or makes transfer difficult.
[0052]
As described above, the dicing adhesive tape 2 having the first regions 3A and 3B shown in FIG. 1 and FIG. 2B is prepared. Dicing and semiconductor chips using the dicing adhesive tape 2 are prepared. The process of peeling off will be described with reference to FIGS.
[0053]
FIG. 4A is a partially cutaway front sectional view showing a state where the dicing adhesive tape 2 is arranged on a stage (not shown) and the semiconductor wafer 1 is bonded to the upper surface thereof.
[0054]
In this state, the semiconductor wafer 1 is firmly bonded to the dicing adhesive tape 2. That is, the first region 3A has a high adhesive strength as described above, and the semiconductor wafer 1 has sufficient adhesive strength to the dicing adhesive tape 2 by the adhesive layer portion constituting the first region 3A. It is pasted together.
[0055]
Next, the semiconductor wafer 1 is diced in the vertical direction and the horizontal direction on the stage. A cutting line X in FIG. 4B indicates a cutting line formed by dicing, and the semiconductor wafer 1 is divided into a large number of semiconductor chips 1A.
[0056]
During dicing, the semiconductor wafer 1 is firmly bonded to the dicing adhesive tape 2, and the dicing adhesive tape 2 is mechanically fixed to a stage (not shown). Misalignment is unlikely to occur. Therefore, dicing is performed with high accuracy.
[0057]
Next, as shown in a schematic partial cutaway sectional view in FIG. 5, light is irradiated from the lower surface of the substrate 4 as indicated by the arrow Z direction. Since the base material 4 is a translucent material, the adhesive constituting the first region 3A is photo-curing by irradiating light from the substrate 4 side, so that the elastic modulus increases, The adhesive force is reduced in the same manner as the second region 3B. In addition, since the gas generating agent described above generates gas, the generated gas moves to the interface between the adhesive surface and the semiconductor wafer 1 in the first region 3A as indicated by the arrow Y, and the adhesive force between the two is increased. It is greatly reduced. That is, while the initial adhesive strength was 100 g / mm or more, the adhesive strength was made almost zero by the light irradiation. Accordingly, the semiconductor chip 1A can be easily peeled off from the dicing adhesive tape 2 using a suction pad or the like, and the semiconductor chip 1A is not easily cracked or chipped when the semiconductor chip 1A is taken out.
[0058]
In the above embodiment, the pressure-sensitive adhesive constituting the first region 3A is composed of a photo-curing pressure-sensitive adhesive that increases in elasticity and decreases in adhesive strength when irradiated with light. It may be constituted by a thermosetting pressure-sensitive adhesive that increases and decreases the adhesive strength. That is, the stimulus for reducing the adhesive strength of the adhesive constituting the first region is not limited to light, and may be other stimuli such as heat.
[0059]
Such a thermosetting pressure-sensitive adhesive is not particularly limited, but includes an acrylic acid alkyl ester-based / methacrylic acid alkyl ester-based polymerizable polymer having a radical polymerizable unsaturated group in the molecule, and a radical. Examples thereof include a thermosetting pressure-sensitive adhesive containing a polymerizable polyfunctional oligomer or monomer as a main component and a thermal polymerization initiator. In this case, for the polymerizable polymer and the polyfunctional oligomer or monomer, the same compounds as in the case of the above-described photocurable pressure-sensitive adhesive can be used.
[0060]
Examples of the thermal polymerization initiator include those that decompose by heat and generate an active radical that initiates polymerization and curing. Specific examples include dicumyl peroxide, di-t-butyl peroxide, and t-butyl. Examples include peroxybenzoyl, t-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, and di-tbutyl peroxide. Among them, 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.
[0061]
In the above-described embodiment, an example in which a gas generating agent that generates gas by light is used is shown. However, a gas generating agent that generates gas by other stimuli such as heat may be included in the adhesive. Good.
[0062]
Moreover, in the said embodiment, although the adhesive containing a gas generating agent was used, in this invention, it is not necessarily necessary to use the adhesive containing the gas generating agent which generate | occur | produces gas by irritation | stimulation. That is, as shown in FIGS. 1A and 1B, the first region 3 </ b> A has a relatively higher adhesive strength than the second region 3 </ b> B in the portion where each semiconductor chip is attached. The gas generating agent does not need to be included as long as sufficient adhesive strength is exhibited during dicing and the semiconductor chip can be easily peeled after dicing.
[0063]
Further, as shown in FIGS. 1A and 1B, in the portion 3 to which each semiconductor chip is attached, only the first region 3A, which is a partial region, has a high adhesive force. You can do it. Therefore, the pressure-sensitive adhesive constituting the first region 3A does not necessarily have to be formed of a pressure-sensitive adhesive whose adhesive force is reduced by a stimulus such as light or heat. That is, since the semiconductor chip is firmly adhered only in the first region 3A, even when an adhesive whose adhesive strength does not decrease by stimulation is used, each individual chip is diced after dicing from the dicing adhesive tape. This is because the semiconductor chip can be easily peeled off.
[0064]
The light irradiation when the semiconductor chip is taken out from the dicing adhesive tape may be applied to the entire region where all the semiconductor chips are attached at one time, or immediately before taking out the individual semiconductor chips. The first region 3A for each semiconductor chip may be irradiated.
[0065]
In the above embodiment, the first region 3 </ b> A and the second region 3 </ b> B are formed by relatively reducing the adhesive force of the second region 3 </ b> B by light irradiation using the mask 6. However, the first region 3A and the second region 3B may be formed by applying different types of adhesives having different adhesive forces. Further, the second region may be configured by arranging another resin material such as a photoresist having no adhesiveness in the second region. Furthermore, no adhesive or resin may be disposed in the second region. That is, the pressure-sensitive adhesive may be applied to the upper surface of the substrate only in the first region 3A to form a dicing pressure-sensitive adhesive tape. However, in that case, since the thickness of the semiconductor wafer is thin, the semiconductor wafer may be wavy.
[0066]
Therefore, it is preferable that an adhesive, a resin, or the like is disposed in the second region 3B so that the upper surfaces of the first and second regions 3A and 3B have flatness as in the above embodiment. .
[0067]
Further, the dicing adhesive tape may be affixed to the surface on the circuit forming surface side of the semiconductor wafer, and after performing the dicing process in advance, the polishing process may be performed.
[0068]
【The invention's effect】
According to the semiconductor chip manufacturing method of the present invention, the dicing adhesive tape is a first region having a relatively high adhesive force in a portion to which one semiconductor chip obtained by dicing a semiconductor wafer is attached. And a second region that has a relatively weak adhesive force or no adhesive force. Therefore, the semiconductor wafer affixed to the dicing adhesive tape is diced into individual semiconductor chips. After the division, the semiconductor chip can be easily peeled from the dicing adhesive tape. Therefore, the semiconductor chip is not easily cracked or chipped during peeling. Further, since the semiconductor chip is only partially adhered to the dicing adhesive tape, the semiconductor chip can be easily peeled off from the dicing adhesive tape as described above. The adhesive strength of the region can be made higher than the initial adhesive strength of the conventional dicing adhesive tape to the semiconductor wafer. Accordingly, the semiconductor wafer is hardly displaced during dicing, and the semiconductor wafer can be diced with high accuracy.
[0069]
In particular, when the adhesive constituting the first region is composed of an adhesive whose adhesive strength is reduced by stimulation, the adhesive strength is reduced by applying stimulation such as light or heat, The semiconductor chip can be more easily peeled off from the dicing adhesive tape. In this case, since the adhesive force is reduced by the stimulus, the initial adhesive force can be sufficiently increased, and the positional deviation of the semiconductor wafer during dicing can be more reliably suppressed.
[0070]
Further, in the case where the pressure-sensitive adhesive contains a gas generating agent that generates gas by stimulation, the gas moves to the interface between the semiconductor chip and the pressure-sensitive adhesive in the first region by applying stimulation such as light or heat. . Therefore, the semiconductor chip can be more easily separated from the dicing adhesive tape without using a push-up pin or the like.
[0071]
As described above, in the present invention, the semiconductor chip is partially strongly adhered to the adhesive tape, so that the peeling can be easily performed. Accordingly, since the adhesive strength of the first region before dicing can be set high, the 180 ° peel adhesive strength with respect to the semiconductor wafer can be set to 100 g / 10 mm or more, and thereby the semiconductor wafer when dicing the semiconductor wafer. Therefore, the semiconductor wafer can be diced with high accuracy.
[Brief description of the drawings]
FIGS. 1A and 1B are a plan view and a part of a dicing adhesive tape prepared in an embodiment of the present invention, schematically showing a portion to which one semiconductor chip is attached. FIG.
FIGS. 2A and 2B are front sectional views of partially cutouts for explaining a process of obtaining the dicing adhesive tape shown in FIG.
FIG. 3 is an exploded perspective view for explaining a process in which a semiconductor wafer is affixed to a dicing adhesive tape according to an embodiment of the present invention.
FIGS. 4A and 4B are a partially cutaway cross-sectional view showing a state in which a semiconductor wafer is stuck on a dicing adhesive tape in one embodiment of the present invention, a semiconductor wafer after dicing, The partial notch front sectional drawing which shows the adhesive tape for dicing.
FIG. 5 is a schematic partially cutaway cross-sectional view for explaining a state in which gas generated from a gas generating agent by light irradiation moves to an interface between an adhesive and a semiconductor chip.
[Explanation of symbols]
1 ... Semiconductor wafer
2 ... Dicing adhesive tape
3A ... 1st area
3B ... 2nd area
4 ... Base material
5 ... Adhesive layer
6 ... Mask
6a ... Opening

Claims (10)

A method for producing a large number of semiconductor chips from a semiconductor wafer,
A process of preparing a semiconductor wafer;
A step of attaching a dicing adhesive tape to the semiconductor wafer, and the dicing adhesive tape has a relatively high adhesive force at a portion where one semiconductor chip obtained by dicing the semiconductor wafer is attached. A first region and a remaining region that has a relatively weak adhesive force or a second region that does not have an adhesive force, and the first region is the one semiconductor chip. Formed in the center of the part to be affixed, the second region is formed around the first region;
Dicing the semiconductor wafer attached to the adhesive tape for dicing, and dividing the semiconductor wafer into individual semiconductor chips;
And a step of peeling the semiconductor chip from the dicing adhesive tape.   2. The method of manufacturing a semiconductor chip according to claim 1, wherein the first region is made of an adhesive whose adhesive strength is reduced by stimulation.   The method of manufacturing a semiconductor chip according to claim 2, wherein the pressure-sensitive adhesive includes a gas generating agent that generates gas by stimulation.   The method of manufacturing a semiconductor chip according to claim 2, wherein the stimulus is light.   5. The method of manufacturing a semiconductor chip according to claim 1, wherein an adhesive force of the first region before dicing is 100 g / 10 mm or more as a 180 ° peel adhesive force to a semiconductor wafer. An adhesive tape for dicing, which is affixed to a semiconductor wafer and separated from the semiconductor wafer into individual semiconductor chips by dicing, and then peeled off from each semiconductor chip. Is a relatively high first region and the remaining region, the second region having a relatively weak adhesive force or no adhesive force , and the first region is the An adhesive tape for dicing, which is formed at the center of one part to which each semiconductor chip part is attached, and wherein the second area is formed around the first area .   The pressure-sensitive adhesive tape for dicing according to claim 6, wherein the first region is composed of an adhesive whose adhesive force is reduced by stimulation.   The pressure-sensitive adhesive tape for dicing according to claim 7, wherein the pressure-sensitive adhesive constituting the first region includes a gas generating agent that generates gas by stimulation.   The adhesive tape for dicing according to claim 7 or 8, wherein the stimulus is light.   The adhesive tape for dicing in any one of Claims 6-9 whose 180 degree peeling adhesive force with respect to the semiconductor wafer of a 1st area | region is 100 g / 10mm or more.

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