KR20180127984A - Semiconductor processing sheet - Google Patents

Abstract

A semiconductor processing sheet having a pressure-sensitive adhesive layer on a substrate and having the following characteristics: a pressure-sensitive adhesive layer having a thickness of 200 占 퐉, wherein the thickness of the pressure-sensitive adhesive layer is 200 占 퐉, When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive force of the adhesive layer to the mirror surface is 200 mN / 25 mm or less.

Description

Semiconductor processing sheet

The present invention relates to a sheet for semiconductor processing.

The present application claims priority based on Japanese Patent Application No. 2016-069603 filed on March 30, 2016, the contents of which are incorporated herein by reference.

The dicing sheet is used to separate the semiconductor wafer into semiconductor chips by dicing. The dicing sheet is constituted by, for example, a pressure-sensitive adhesive layer on a substrate, and the pressure-sensitive adhesive layer is used by being attached to a semiconductor wafer. After the dicing, the semiconductor chip is separated from the cured pressure-sensitive adhesive layer and easily picked up, for example, by lowering the adhesive force of the pressure-sensitive adhesive layer by curing by irradiation of energy rays such as ultraviolet rays.

On the other hand, the picked-up semiconductor chip is die-bonded to the circuit surface of the substrate by, for example, a film-like adhesive, and if necessary, one or more other semiconductor chips are further laminated on the semiconductor chip, The whole is sealed with resin.

By using the semiconductor package thus obtained, a desired semiconductor device is finally manufactured. Therefore, there is a case where the semiconductor chip is configured to be picked up with a film-like adhesive on the surface to be die-bonded.

As described above, in the case of using a film-like adhesive, a dicing die bonding sheet in which an uncut film-like adhesive is formed on the pressure-sensitive adhesive layer of the dicing sheet may be used. On the other hand, there are cases where a plurality of semiconductor chips, which have been previously separated, are formed on a film-like adhesive, and in this case also, a processing sheet having the same structure as the dicing die bonding sheet is used. In the case of using such a processing sheet, for example, a plurality of semiconductor chips, which are previously separated on the film-like adhesive, are formed, and the processing sheet is expanded under a low temperature so that the film- There is a case where a semiconductor chip having a film-like adhesive agent after cutting is produced on a desired surface.

Examples of the processing sheet (wafer processing tape) suitable for cutting the film-like adhesive agent by extender include a pressure-sensitive adhesive layer and a film-like adhesive agent (adhesive layer) having a shearing force of 0.2 N / , The peel strength of the pressure-sensitive adhesive layer and the film-like adhesive at a peeling speed of 300 mm / min in a standard state according to JIS-Z0237 after irradiation with energy rays of 200 mJ / cm 2 and a peeling angle of 180 degrees was 0.3 N / (See Patent Document 1).

International Publication No. 2013/103116

However, the processing sheet disclosed in Patent Document 1 has a problem that energy ray irradiation is required at the time of use. In the case of this cutting sheet, in order to suppress lifting and scattering of the semiconductor chip having a film-like adhesive agent from the pressure-sensitive adhesive layer, the adhesive strength of the pressure-sensitive adhesive layer before the energy ray irradiation is designed to be high On the other hand, in order to facilitate pickup of a semiconductor chip having a film-like adhesive agent, the adhesive force of the pressure-sensitive adhesive layer after irradiation with energy rays is designed to be lowered.

Accordingly, the present invention provides a semiconductor processing sheet for use in cutting a film-like adhesive adhered to a semiconductor chip, which is provided with a pressure-sensitive adhesive layer on a substrate, It is an object of the present invention to provide a semiconductor processing sheet capable of suppressing lifting and scattering of a semiconductor chip having a film-like adhesive agent from a pressure-sensitive adhesive layer and capable of easily picking up a semiconductor chip having a film- The purpose.

In order to solve the above problems, the present invention provides a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer on a substrate, wherein the pressure-sensitive adhesive layer having a thickness of 200 占 퐉 has a storage elastic modulus at 0 占 폚 of 1000 MPa or less, The adhesive strength of which is 200 mN / 25 mm or less.

In the sheet for semiconductor processing of the present invention, it is preferable that the pressure-sensitive adhesive layer is non-energy ray curable.

The sheet for semiconductor processing of the present invention may further comprise a film-like adhesive on the pressure-sensitive adhesive layer.

[1] A semiconductor processing sheet having a pressure-sensitive adhesive layer on a substrate and having the following characteristics:

Wherein the pressure-sensitive adhesive layer having a thickness of 200 mu m has a storage elastic modulus at 0 deg. C of 1000 MPa or less, when the thickness of the pressure-sensitive adhesive layer is 200 mu m,

When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive force of the pressure sensitive adhesive layer to the mirror surface is 200 mN / 25 mm or less.

[2] The sheet for semiconductor processing according to [1], wherein the pressure-sensitive adhesive layer is non-energy radiation curable.

[3] The semiconductor processing sheet according to [1] or [2], further comprising a film-like adhesive on the pressure-sensitive adhesive layer.

According to the present invention, there is provided a semiconductor processing sheet comprising a pressure-sensitive adhesive layer on a substrate and used for cutting a film-like adhesive adhered to a semiconductor chip, wherein energy radiation at the time of use is unnecessary, There is provided a semiconductor processing sheet capable of suppressing lifting and scattering of a semiconductor chip having a film-like adhesive from a pressure-sensitive adhesive layer and capable of easily picking up a semiconductor chip having a film-like adhesive.

1 is a cross-sectional view schematically showing an embodiment of a semiconductor processing sheet of the present invention.
2 is a cross-sectional view for schematically explaining an embodiment of a method of manufacturing a semiconductor device when the semiconductor processing sheet of the present invention is used.
3 is a cross-sectional view schematically illustrating one embodiment of a method of forming a groove in a semiconductor wafer to obtain a semiconductor chip.
4 is a cross-sectional view schematically illustrating one embodiment of a method of forming a modified layer on a semiconductor wafer to obtain a semiconductor chip.
Fig. 5 is a cross-sectional view schematically showing the state of a semiconductor chip at the time of exposing a film-like adhesive when a conventional semiconductor processing sheet is used.
6 is a cross-sectional view schematically showing a state when an attempt is made to pick up a semiconductor chip on which a film-like adhesive is formed when a conventional semiconductor processing sheet is used.

<< Sheet for semiconductor processing >>

The sheet for semiconductor processing of the present invention comprises a pressure-sensitive adhesive layer on a substrate, wherein the pressure-sensitive adhesive layer having a thickness of 200 占 퐉 has a storage elastic modulus at 0 占 폚 of 1000 MPa or less and an adhesive force of the pressure- 200 mN / 25 mm or less.

In another aspect, the semiconductor processing sheet of the present invention is a sheet for semiconductor processing having a pressure-sensitive adhesive layer on a substrate and having the following characteristics:

Wherein the pressure-sensitive adhesive layer having a thickness of 200 mu m has a storage elastic modulus at 0 deg. C of 1000 MPa or less, when the thickness of the pressure-sensitive adhesive layer is 200 mu m,

When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive force of the pressure sensitive adhesive layer to the mirror surface is 200 mN / 25 mm or less.

The semiconductor processing sheet of the present invention has a structure in which a film-like adhesive agent is formed on the pressure-sensitive adhesive layer and a plurality of semiconductor chips having been divided in advance are formed on the film-like adhesive, The film-like adhesive is applied to the outer shape of the semiconductor chip by expanding the adhesive in the direction of the surface thereof (the direction along the surface, that is, the direction horizontal to the surface of the adhesive on the film) For example, in the step of cutting. (In this specification, &quot; a film-like adhesive agent &quot;) having the film-like adhesive agent after cutting is formed on the surface (back surface) opposite to the surface on which the circuit is formed Quot; formed semiconductor chip &quot;) is used for manufacturing a semiconductor device after being picked up.

As described above, the semiconductor processing sheet of the present invention is preferably used as an expanse sheet in which an adhesive agent on a film is extruded and cut.

The semiconductor processing sheet of the present invention is also preferably used as a dicing sheet alone.

According to the semiconductor processing sheet of the present invention, at the time of cutting by the extender of the film-like adhesive agent formed on the semiconductor processing sheet, the adhesive agent layer (that is, the semiconductor processing sheet in the semiconductor chip) And it is possible to easily pick up a semiconductor chip on which a film-like adhesive agent has been formed without involving a process abnormality.

The cutting by the extender of the film-like adhesive as described above is preferable for application when manufacturing a semiconductor chip in which a film-like adhesive having a thin semiconductor chip is formed, for example.

The plurality of divided semiconductor chips are formed, for example, on the circuit forming surface (surface) opposite to the adhesive surface (back surface) of the film-like adhesive in the semiconductor wafer, For example. Thus, the operation of dividing the semiconductor wafer so as not to divide the semiconductor wafer and leaving the bottom of the groove is referred to as a half cut. However, the term &quot; half cut &quot; in the present invention does not mean only the operation of dropping the semiconductor wafer so that the depth of the groove becomes a specific value such as, for example, half the thickness of the semiconductor wafer. Quot; is meant to mean the entire operation for dropping the semiconductor wafer so as to leave the semiconductor wafer.

As a method of forming the grooves, for example, a method of forming grooves by cutting a semiconductor wafer using a blade (i.e., blade dicing), a method of forming grooves by inserting a semiconductor wafer by laser irradiation (E.g., laser dicing), and a method of forming grooves by inserting a semiconductor wafer by jetting water containing an abrasive (i.e., water dicing). However, in the case of manufacturing a semiconductor chip by cutting out a part of the semiconductor wafer as described above, if the thickness of the semiconductor wafer is thin, a cracked semiconductor chip tends to be obtained and the yield tends to be lowered. In addition, since the cutting residuals in the form of beard in the semiconductor chip remain or the cutting residue of the semiconductor wafer adheres to the semiconductor chip, an abnormality occurs in picking up the semiconductor chip in which the film-like adhesive is formed or the performance of the obtained semiconductor device is deteriorated .

On the other hand, a plurality of divided semiconductor chips are irradiated with laser light in an infrared range so as to be converged to a predetermined focal point inside the semiconductor wafer to form a modified layer inside the semiconductor wafer, and then the back surface of the semiconductor wafer is ground Further, by applying a force at the time of grinding to the semiconductor wafer while grinding the back surface, the semiconductor wafer can be divided at the formation site of the modified layer. In this method, since there is no step of cutting out a part of the semiconductor wafer, even if the thickness of the semiconductor wafer is thin, cracks of the semiconductor chip as described above, remaining of cutting residues in the semiconductor chip, And the like.

As described above, the method of dividing the semiconductor wafer at the formation site of the modified layer is preferable when the thickness of the semiconductor wafer is thin. When picking up a semiconductor chip having a thin thickness obtained from such a semiconductor wafer together with the adhesive agent, A sheet for semiconductor processing is preferable.

<Description>

Specific examples of the constituent material of the substrate include various resins such as polyethylene (low density polyethylene (sometimes abbreviated as LDPE), linear low density polyethylene (sometimes abbreviated as LLDPE), and high density polyethylene ( HDPE), etc.), polypropylene, polybutene, polybutadiene, polymethylpentene, styrene / ethylene butylene / styrene block copolymer, polyvinyl chloride, vinyl chloride copolymer, polyethylene terephthalate, polybutyl (Meth) acrylic acid copolymers, ethylene / (meth) acrylic acid ester copolymers, polystyrene, polycarbonate, fluorine-containing resins such as polyvinylidene fluoride, polyvinylidene fluoride, Resins, water additives, modified products, crosslinked products, and copolymers of any of these resins.

Of these, low-density polyethylene (LDPE) is preferred.

Meanwhile, in the present specification, the term "(meth) acrylic acid" includes both "acrylic acid" and "methacrylic acid". The term "(meth) acrylate" is a concept including both "acrylate" and "methacrylate", and the term "(meth) acrylate" Diary "is a concept including both" acryloyl group "and" methacryloyl group ".

The resin constituting the base material may be one kind alone, or two or more kinds thereof, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

The base material may be composed of one layer (single layer), or may be composed of plural layers of two or more layers. When the base material is composed of a plurality of layers, the plurality of layers may be the same or different, and the combination of these layers is not particularly limited so long as the effect of the present invention is not impaired.

In the present specification, the term &quot; a plurality of layers may be equal to or different from each other &quot; is not limited to the case of the base material. The term &quot; all layers may be the same or all layers may be different, Means that at least one of the constituent material and the thickness of each layer is different from each other ". The term &quot; a plurality of layers are different from each other &quot;

The thickness of the base material can be appropriately selected according to the purpose, but it is preferably 50 to 300 mu m, more preferably 70 to 150 mu m.

Here, the &quot; thickness of the substrate &quot; means the thickness of the entire substrate, and for example, the thickness of the substrate composed of plural layers means the total thickness of all the layers constituting the substrate.

In the present specification, the term &quot; thickness &quot; means a value expressed by an average obtained by measuring the thickness of the contact type thickness meter at any five points.

In order to improve adhesion with other layers such as a pressure-sensitive adhesive layer formed thereon, the substrate may be subjected to a surface treatment such as a sandblasting treatment, a surface treatment by a solvent treatment, a corona discharge treatment, an electron beam irradiation treatment, a plasma treatment, Oxidation treatment such as flame treatment, chromic acid treatment, hot air treatment, or the like may be performed on the surface.

Further, the surface of the substrate may be subjected to a primer treatment.

When the antistatic coat layer and the semiconductor processing sheet are stacked and stored, the substrate may have a layer for preventing the substrate from adhering to another sheet, a layer for preventing the substrate from adhering to the adsorption table, and the like.

<Pressure-sensitive adhesive layer>

The pressure-sensitive adhesive layer preferably satisfies the conditions of storage elastic modulus shown below and is non-energy ray curable.

In the present invention, &quot; non-energy ray curable property &quot; means a property of not curing even when irradiated with an energy ray. On the contrary, the property to be cured by irradiating the energy ray is called "energy ray hardenability".

In the present invention, the term &quot; energy ray &quot; means having both energy in an electromagnetic wave or a charged particle beam, and examples thereof include ultraviolet rays and electron rays.

Ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, a light emitting diode, or the like as an ultraviolet ray source. The electron beam can be irradiated by an electron beam accelerator or the like.

The pressure-sensitive adhesive layer may have only one layer (single layer), or may have a plurality of layers of two or more layers. In the case of a plurality of layers, these layers may be mutually the same or different, and combinations of these layers are not particularly limited.

The thickness of the pressure-sensitive adhesive layer can be appropriately selected according to the purpose, but is preferably 1 to 100 占 퐉, more preferably 1 to 60 占 퐉, and particularly preferably 1 to 30 占 퐉.

Here, the "thickness of the pressure-sensitive adhesive layer" means the total thickness of the pressure-sensitive adhesive layer. For example, the thickness of the pressure-sensitive adhesive layer composed of plural layers means the total thickness of all layers constituting the pressure-sensitive adhesive layer.

The pressure-sensitive adhesive layer for obtaining the storage elastic modulus may be a single-layer pressure-sensitive adhesive layer having a thickness of 200 占 퐉 or a laminate obtained by laminating two or more pressure-sensitive adhesive layers having a thickness of less than 200 占 퐉 so as to have a total thickness of 200 占 퐉.

On the other hand, in the present specification, the pressure-sensitive adhesive layer for which the storage elastic modulus is to be obtained is sometimes referred to simply as a "pressure-sensitive adhesive layer", regardless of whether it is a single-layer pressure-sensitive adhesive layer or a laminate.

In the present specification, the above-mentioned &quot; storage elastic modulus of pressure-sensitive adhesive layer &quot; and &quot; storage elastic modulus of laminate &quot;, unless otherwise specified, Quot; and &quot; storage elastic modulus of the laminate before the pressure-sensitive adhesive layer is cured &quot;.

The pressure-sensitive adhesive layer or the laminate preferably has a storage elastic modulus at 0 占 폚 of 1000 MPa or less and 996 MPa or less. When the storage elastic modulus is equal to or less than the upper limit value, lifting and scattering of the semiconductor chip on which the film-like adhesive is formed from the pressure-sensitive adhesive layer is suppressed at the time of cutting by expanding the film-like adhesive as described later.

The lower limit value of the storage elastic modulus at 0 占 폚 of the pressure-sensitive adhesive layer or the laminate is not particularly limited and may be, for example, 100 MPa, 300 MPa or 500 MPa, but these are merely examples.

That is, as one aspect, the pressure-sensitive adhesive layer or the laminate has a storage elastic modulus at 100 占 폚 of 1000 MPa, preferably 300 MPa to 1000 MPa, more preferably 500 MPa to 996 MPa, and particularly preferably 533 MPa to 999 MPa at 0 占 폚.

In the present invention, the storage elastic modulus (MPa) is a temperature at which the pressure-sensitive adhesive layer or laminate to be measured is heated at a temperature raising rate of 10 캜 / min and a frequency of 11 Hz, for example, (MPa) at the time when the temperature is raised in the range.

More specifically, when the thickness of the pressure-sensitive adhesive layer is 200 占 퐉, the temperature is raised at a temperature raising rate of 10 占 폚 / min, a frequency of 11Hz, and a temperature of -50 占 폚 to 50 占 폚 by a dynamic viscoelasticity measuring apparatus at 0 占 폚 (MPa) of the resin in the resin.

The storage elastic modulus can be appropriately adjusted by, for example, controlling the type and amount of the component contained in the pressure-sensitive adhesive layer.

For example, the storage modulus of the pressure-sensitive adhesive layer and the storage modulus of the laminate can be easily controlled by adjusting the ratio of the monomer constituting the pressure-sensitive adhesive resin, the amount of the crosslinking agent, the content of the filler, and the like.

However, these adjustment methods are merely examples.

In the sheet for semiconductor processing of the present invention, the adhesive force of the pressure-sensitive adhesive layer to the semiconductor wafer (adhesion to the mirror surface of the semiconductor wafer) is preferably 200 mN / 25 mm or less and 196 mN / 25 mm or less. When the adhesive force is not more than the upper limit value, the semiconductor chip on which the film-like adhesive is formed can be easily picked up without curing the pressure-sensitive adhesive layer by energy ray irradiation or the like as described later.

The lower limit value of the adhesive force of the pressure-sensitive adhesive layer to the semiconductor wafer is not particularly limited and may be, for example, 10 mN / 25 mm, 30 mN / 25 mm, or 50 mN / 25 mm.

That is, as one aspect, the adhesive force of the pressure-sensitive adhesive layer of the semiconductor processing sheet of the present invention to the semiconductor wafer is 10 to 200 mN / 25 mm, preferably 30 to 200 mN / 25 mm, More preferably 55 to 194 mN / 25 mm.

In the present specification, the "adhesive force of the pressure-sensitive adhesive layer to a semiconductor wafer" means "adhesive force of the pressure-sensitive adhesive layer before curing" when the pressure-sensitive adhesive layer is curable, unless otherwise specified. In addition, the measurement of the adhesive force is a measurement of the adhesive force in the standard state prescribed in JIS Z0237 2008, unless otherwise specified.

In the present invention, the adhesive force (mN / 25 mm) can be measured by the following method. That is, the semiconductor processing sheet having a width of 25 mm and an arbitrary length is manufactured. Subsequently, the semiconductor processing sheet is bonded to the semiconductor wafer (that is, the mirror surface of the semiconductor wafer) by a pressure-sensitive adhesive layer at room temperature (for example, 23 DEG C). At this temperature, so-called 180 deg. Peeling is performed in which the semiconductor processing sheet is peeled from the semiconductor wafer at a peeling rate of 300 mm / min so that the surfaces of the pressure sensitive adhesive layer and the semiconductor wafer, which are in contact with each other, . The peeling force at this time is measured, and the measured value is defined as the above adhesive force (mN / 25 mm). The length of the semiconductor processing sheet provided for the measurement is not particularly limited as long as the peeling force can be stably measured. For example, the length of the semiconductor processing sheet provided for measurement may be 150 mm.

The semiconductor wafer is, for example, a silicon wafer.

The adhesive force of the pressure-sensitive adhesive layer to the semiconductor wafer can be appropriately adjusted by, for example, controlling the kind and amount of the components contained in the pressure-sensitive adhesive layer.

For example, the adhesive force of the pressure-sensitive adhesive layer can be easily controlled by controlling the combination of monomers constituting the pressure-sensitive adhesive resin to be described later, the ratio of the monomer, the amount of the crosslinking agent, and the content of the filler.

However, these adjustment methods are merely examples.

In the case where semiconductor wafers such as silicon wafers are different in kind, or the same type and the production lot is different, if the same pressure-sensitive adhesive layer is applied to the same portion, the deviation of adhesive force with the pressure- Therefore, the adhesive force of the pressure-sensitive adhesive layer can be specified with high precision by selecting a semiconductor wafer as the measurement object. In the present invention, by selecting the pressure-sensitive adhesive layer having an adhesive force of 200 mN / 25 mm or less to the mirror surface of the semiconductor wafer, it is possible to suppress the occurrence of the process abnormality when the semiconductor chip on which the film- The adhesive force of the pressure-sensitive adhesive layer to the adhesive agent on the film can be adjusted so that the pressure-sensitive adhesive layer can be easily picked up. The effects of the present invention are expressed in the whole of the film adhesive used in this field.

The pressure-sensitive adhesive layer may be formed of a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, a pressure-sensitive adhesive composition may be coated on the surface of the pressure-sensitive adhesive layer to be formed and, if necessary, dried to form a pressure-sensitive adhesive layer on a desired portion. A more specific method of forming the pressure-sensitive adhesive layer will be described in detail later, together with a method of forming the other layer. The ratio of the content of components not vaporized at room temperature in the pressure-sensitive adhesive composition is generally the same as the content of the components in the pressure-sensitive adhesive layer.

The coating of the pressure-sensitive adhesive composition may be carried out by a known method. For example, the pressure-sensitive adhesive composition may be applied by a known method, for example, an air knife coater, blade coater, bar coater, gravure coater, roll coater, roll knife coater, curtain coater, die coater, And a method of using various coaters such as a coater and a kiss coater.

The drying conditions of the pressure-sensitive adhesive composition are not particularly limited, but it is preferable to heat and dry the pressure-sensitive adhesive composition when it contains a solvent to be described later. In this case, for example, at 70 to 130 캜 for 10 seconds to 5 minutes It is preferable to dry it.

[Pressure sensitive adhesive composition]

The pressure-sensitive adhesive composition is preferably non-energy ray curable.

Examples of the non-energy radiation curable pressure-sensitive adhesive composition include pressure-sensitive adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, or polycarbonate (hereinafter, Quot;). &Lt; / RTI &gt;

(Adhesive resin (i))

The viscous resin (i) is preferably the acrylic resin.

Examples of the acrylic resin in the viscous resin (i) include an acrylic polymer having a constituent unit derived from at least a (meth) acrylic acid alkyl ester.

The acrylic resin may have only one constituent unit, or two or more constituent units, and in the case of two or more constituent units, the combination and ratio thereof may be arbitrarily selected.

Here, "derived" means that the chemical structure is changed to polymerize.

As the alkyl (meth) acrylate, for example, the alkyl group constituting the alkyl ester may have 1 to 20 carbon atoms, and the alkyl group is preferably a straight chain or branched chain.

Specific examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (Meth) acrylate, isobutyl acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (Meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, undecyl (Meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate (also referred to as myristyl (meth) acrylate), pentadecyl (meth) acrylate, hexadecyl (Also referred to as palmityl acrylate), heptadecyl (meth) acrylate, (Meth) acrylic acid octadecyl (also referred to as stearyl (meth) acrylate), nonadecyl (meth) acrylate, and eicosyl (meth) acrylate.

Of these, 2-ethylhexyl (meth) acrylate is preferred.

From the viewpoint that the adhesive force of the pressure-sensitive adhesive layer is improved, it is preferable that the acrylic polymer has a constituent unit derived from a (meth) acrylic acid alkyl ester in which the number of carbon atoms in the alkyl group is 4 or more. Further, the number of carbon atoms of the alkyl group is preferably 4 to 12, more preferably 4 to 8, from the standpoint that the adhesive force of the pressure-sensitive adhesive layer is further improved. Also, the (meth) acrylic acid alkyl ester having 4 or more carbon atoms in the alkyl group is preferably an acrylic acid alkyl ester.

In addition to the constituent unit derived from the alkyl (meth) acrylate, the acrylic polymer preferably has a constituent unit derived from a monomer having a functional group.

As the functional group-containing monomer, for example, the functional group reacts with a crosslinking agent to be described later to become a starting point of crosslinking, or the functional group reacts with the unsaturated group in the unsaturated group-containing compound to enable introduction of an unsaturated group into the side chain of the acrylic polymer .

Examples of the functional group in the functional group-containing monomer include a hydroxyl group, a carboxyl group, an amino group, and an epoxy group.

That is, examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer.

Examples of the hydroxyl group-containing monomer include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl Hydroxyalkyl (meth) acrylate such as 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; (Meth) acrylic unsaturated alcohols (unsaturated alcohols having no (meth) acryloyl skeleton) such as vinyl alcohol and allyl alcohol.

Of these, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are preferred.

Examples of the monomer containing a carboxyl group include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having ethylenic unsaturated bonds) such as (meth) acrylic acid and crotonic acid; Ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having ethylenic unsaturated bonds) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; An anhydride of the ethylenically unsaturated dicarboxylic acid; And (meth) acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate.

The functional group-containing monomer is preferably a hydroxyl group-containing monomer or a carboxyl group-containing monomer, and more preferably a hydroxyl group-containing monomer.

The functional group-containing monomers constituting the acrylic polymer may be either one kind alone or two or more types, and in the case of two or more types, the combination and ratio thereof may be arbitrarily selected.

The content of the constituent unit derived from the functional group-containing monomer in the acrylic polymer is preferably 1 to 35% by mass, more preferably 3 to 32% by mass relative to the total amount (total mass) of the constituent units constituting the acrylic polymer , And particularly preferably from 5 to 30 mass%.

The acrylic polymer may further contain constituent units derived from alkyl (meth) acrylate and constituent units derived from other monomer besides constituent units derived from a monomer having a functional group.

The other monomer is not particularly limited as long as it is copolymerizable with (meth) acrylic acid alkyl ester and the like.

Examples of the other monomer include styrene,? -Methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide and the like.

The above-mentioned other monomers constituting the acrylic polymer may be either one kind alone or two or more kinds thereof, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

The adhesive resin (i) other than the acrylic polymer preferably has a constituent unit derived from a monomer having a functional group, like the acrylic polymer.

The adhesive resin (i) contained in the pressure-sensitive adhesive composition may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

The content of the adhesive resin (i) is preferably from 45 to 90 mass%, more preferably from 55 to 87 mass% (based on the total mass of the pressure-sensitive adhesive layer) of the total mass of components other than the solvent constituting the pressure- More preferably from 65 to 84% by mass, still more preferably from 72 to 81% by mass. When the ratio of the content of the adhesive resin (i) is in this range, the adhesive property of the pressure-sensitive adhesive layer becomes better.

(Crosslinking agent (ii))

The pressure-sensitive adhesive composition preferably contains a crosslinking agent (ii).

The crosslinking agent (ii) reacts with, for example, the functional group to crosslink the adhesive resin (i).

Examples of the crosslinking agent (ii) include isocyanate crosslinking agents (that is, crosslinking agents having isocyanate groups) such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; An epoxy crosslinking agent such as ethylene glycol glycidyl ether (i.e., a crosslinking agent having a glycidyl group); Aziridine crosslinking agents (i.e., crosslinking agents having an aziridinyl group) such as hexa [1- (2-methyl) -aziridinyl] triphospatriazine; A metal chelate type crosslinking agent such as an aluminum chelate (i.e., a crosslinking agent having a metal chelate structure); Isocyanurate crosslinking agents (i.e., crosslinking agents having an isocyanuric acid skeleton), and the like.

The cross-linking agent (ii) is preferably an isocyanate-based cross-linking agent, for example, from the standpoint of improving the cohesive force of the pressure-sensitive adhesive to improve the adhesive force of the pressure- And the like.

The crosslinking agent (ii) contained in the pressure-sensitive adhesive composition may be one kind or two or more kinds, and when two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

When the pressure-sensitive adhesive composition contains the crosslinking agent (ii), the content of the crosslinking agent (ii) in the pressure-sensitive adhesive composition is preferably 5 to 50 parts by mass, more preferably 10 to 45 parts by mass More preferably 15 to 40 parts by mass, and particularly preferably 15 to 40 parts by mass. In another aspect, the content of the crosslinking agent (ii) may be 22 to 38 mass parts or 22.62 to 37.70 mass parts per 100 mass parts of the adhesive resin (i). Since the content of the crosslinking agent (ii) is the lower limit value or more, the effect of using the crosslinking agent (ii) is more remarkably obtained. Further, when the content of the crosslinking agent (ii) is not more than the upper limit value, adjustment of the adhesive force of the pressure-sensitive adhesive layer to the film-like adhesive becomes easier.

(Other additives)

The pressure-sensitive adhesive composition may contain other additives not falling within any of the above-mentioned ranges within the range not hindering the effect of the present invention.

Examples of the other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers (fillers), rust inhibitors, colorants (pigments and dyes), sensitizers, tackifiers, Catalyst), and the like.

On the other hand, the term &quot; reaction retarder &quot; means, for example, suppressing the progress of the crosslinking reaction which is not intended in the pressure-sensitive adhesive composition to be preserved by the action of the catalyst incorporated into the pressure- Examples of the reaction delaying agent include compounds that form a chelate complex with a chelate to a catalyst, and more specifically, a compound having two or more carbonyl groups (-C (= O) -) in one molecule .

The other additives contained in the pressure-sensitive adhesive composition may be one kind or two or more kinds, and in the case of two or more kinds, the combination and ratio thereof may be arbitrarily selected.

In the pressure-sensitive adhesive composition, the content of other additives is not particularly limited and may be appropriately selected depending on the kind thereof.

(menstruum)

The pressure-sensitive adhesive composition may contain a solvent. Since the pressure-sensitive adhesive composition contains a solvent, the coating applicability to the coating target surface is improved.

The solvent is preferably an organic solvent. Examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; Esters such as ethyl acetate (for example, carboxylic acid esters); Ethers such as tetrahydrofuran and dioxane; Aliphatic hydrocarbons such as cyclohexane and n-hexane; Aromatic hydrocarbons such as toluene and xylene; 1-propanol, 2-propanol, and other alcohols.

As the solvent, for example, the solvent used in the production of the adhesive resin (i) may be used as it is in the adhesive composition as it is without removing it from the adhesive resin (i) A solvent of the same or different type as the solvent may be added separately in the production of the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition may contain only one type of solvent, two or more types of solvents, and combinations and ratios of two or more types may be selected arbitrarily.

In the pressure-sensitive adhesive composition, the content of the solvent is not particularly limited and may be appropriately adjusted.

[Production method of pressure-sensitive adhesive composition]

The pressure-sensitive adhesive composition is obtained by blending each component for constituting the pressure-sensitive adhesive composition.

The order of addition in the mixing of the respective components is not particularly limited, and two or more components may be added at the same time.

In the case of using a solvent, the solvent may be mixed with any of the ingredients other than the solvent to dilute the former in advance, or a solvent may be mixed with the latter without diluting any of the ingredients other than the solvent .

A method of mixing the respective components at the time of mixing is not particularly limited, and a method of mixing and stirring an agitator or an agitating blade; A method of mixing using a mixer; And a method of adding and mixing ultrasonic waves.

The temperature and time at the time of addition and mixing of the respective components are not particularly limited as long as they do not deteriorate the respective components, and the temperature and time are preferably adjusted to 15 to 30 캜.

1 is a cross-sectional view schematically showing an embodiment of a semiconductor processing sheet of the present invention. In order to facilitate understanding of the features of the present invention, the drawings used in the following description may be enlarged in major portions for convenience, and the dimensional ratios and the like of the respective components may be the same as actual none.

The semiconductor processing sheet 1 shown in Fig. 1 is a sheet formed by forming a pressure-sensitive adhesive layer 12 on a substrate 11. Fig. In the sheet for semiconductor processing 1, the pressure-sensitive adhesive layer 12 is laminated on one surface 11a of the base material 11.

On the other hand, the semiconductor processing sheet of the present invention is not limited to the one shown in Fig. 1 and may be modified, deleted, or added to a part of the structure shown in Fig. 1 within a range not hindering the effect of the present invention.

<< Process for producing a sheet for semiconductor processing >>

The semiconductor processing sheet of the present invention can be produced by laminating a pressure-sensitive adhesive layer on a substrate. The method of forming the pressure-sensitive adhesive layer is as described above.

For example, a pressure-sensitive adhesive composition is coated on a release film and, if necessary, dried to form a pressure-sensitive adhesive layer on the release film. The pressure-sensitive adhesive layer thus formed is exposed on the side opposite to the side in contact with the release film By bonding the surface with one surface of the base material, the above-described semiconductor processing sheet is obtained. The release film may be removed at any timing after the sheet for semiconductor processing is obtained. It is preferable that the pressure-sensitive adhesive composition is coated on the release-treated surface of the release film.

Further, the semiconductor processing sheet is usually kept in a state in which a release film is stuck to the surface of the outermost layer (that is, the pressure-sensitive adhesive layer) opposite to the substrate. Therefore, after the pressure-sensitive adhesive layer is formed on the release film by the above-described method, the pressure-sensitive adhesive layer may remain bonded even after the pressure-sensitive adhesive layer is bonded to the substrate without removing the release film.

<< Method of Manufacturing Semiconductor Device >>

As a method of manufacturing a semiconductor device using the semiconductor processing sheet of the present invention, for example, there is a method in which a film-like adhesive agent is formed on the surface of a pressure-sensitive adhesive layer in the semiconductor processing sheet, (Hereinafter may be abbreviated as &quot; laminate structure forming step &quot; in some cases) of forming a laminate structure on which a plurality of divided semiconductor chips are formed on the surface opposite to the side where the layer is formed, (Hereinafter sometimes abbreviated as "cutting step") of cutting the film-like adhesive by expanding the film-like adhesive in the direction of the surface of the film-like adhesive while cooling the film-like adhesive, (That is, a semiconductor chip on which a film-like adhesive is formed) having the adhesive layer It is), and the production method, which comprises the steps (in some cases hereinafter abbreviated as "separating step").

By using the semiconductor processing sheet of the present invention, in the cutting step, when the extruder of the semiconductor processing sheet, in other words, the film-like adhesive agent is cut by expanding the film-like adhesive, Is prevented from being lifted or scattered from the pressure-sensitive adhesive layer. Further, in the separation step, the semiconductor chip on which the film-like adhesive is formed can be easily separated from the pressure-sensitive adhesive layer and picked up without curing the pressure-sensitive adhesive layer by energy ray irradiation or the like. Thus, in the case of using the semiconductor processing sheet of the present invention, the semiconductor chip having the film-like adhesive can be picked up without curing the pressure-sensitive adhesive layer, so that the manufacturing process of the semiconductor device can be simplified.

Hereinafter, the manufacturing method will be described with reference to FIG. 2 is a cross-sectional view for schematically explaining an embodiment of a method of manufacturing a semiconductor device when the semiconductor processing sheet of the present invention is used. Here, a manufacturing method when the semiconductor processing sheet shown in Fig. 1 is used will be described. On the other hand, in Fig. 2, the same components as those shown in Fig. 1 are denoted by the same reference numerals as those in Fig. 1, and a detailed description thereof will be omitted. In Fig. 2, only the structures related to the semiconductor processing sheet, the film-like adhesive and the semiconductor chip are shown in cross section. These are the same also in the drawings after FIG.

&Lt; Laminating structure forming step &

The laminated structure 101 shown in Fig. 2 (a) is formed by laminating the surface 12a of the pressure-sensitive adhesive layer 12 of the semiconductor processing sheet 1 (the side opposite to the side provided with the substrate in the pressure-sensitive adhesive layer 12) And a plurality of divided semiconductor chips 8 are formed on the surface 9a of the film adhesive 9 opposite to the side having the adhesive layer 12 Laminated structure. On the other hand, the semiconductor processing sheet 1 is a semiconductor processing sheet of the present invention in which a pressure-sensitive adhesive layer 12 is laminated on the surface 11a of the base material 11.

In Fig. 2, void portions (derived from the grooves) between the plurality of semiconductor chips 8 are emphatically displayed.

In the laminated structure forming step, for example, a single film-like adhesive (not shown) is applied to the rear surface 8b of the divided semiconductor chips 8 (the surface opposite to the circuit forming surface of the semiconductor chip 8) The adhesive 9 for the semiconductor processing sheet 1 of the present invention is applied to the surface 9b of the film adhesive 9 opposite to the side where the semiconductor chip 8 is provided, The laminated structure 101 can be formed by pasting the layer 12. A single film adhesive 9 is applied to the surface 12a of the pressure sensitive adhesive layer 12 of the semiconductor processing sheet 1 of the present invention and then the pressure sensitive adhesive layer The laminated structure can also be formed by attaching the surface 9a opposite to the side provided with the semiconductor chip 8 to the backside 8b of the divided semiconductor chips 8. [

As described above, the divided plurality of semiconductor chips 8 form grooves from the circuit formation surface (surface) opposite to the application surface (back surface) of the film-like adhesive 9 in the semiconductor wafer, And then grinding the back surface until reaching. The groove may be formed by a method such as blade dicing, laser dicing or water dicing.

3 is a cross-sectional view for schematically explaining an embodiment of a method of forming a groove in such a semiconductor wafer to obtain a semiconductor chip.

In this method, as shown in Fig. 3 (a), a semiconductor wafer 8 'is subjected to dicing by laser dicing, laser dicing, water dicing or the like from one surface 8a' 80 ').

Next, as shown in Fig. 3 (b), the surface (back surface) 8b 'opposite to the surface (circuit forming surface) 8a' of the semiconductor wafer 8 'is ground. The grinding of the back surface 8b 'can be performed by a known method, for example, using a grinder 62. [ The grinding of the back surface 8b 'is preferably performed by attaching the back grind tape 63 to the surface 8a' of the semiconductor wafer 8 'as shown here.

3 (c), a plurality of semiconductor chips 8 are obtained from the semiconductor wafer 8 'by grinding the back surface 8b' until reaching the groove 80 '. The back surface 8b 'of the semiconductor wafer 8' becomes a surface for forming the back surface 8b of the semiconductor chip 8, that is, the film adhesive 9.

However, in the above-described manufacturing method of the semiconductor device, as described above, the modified layer is formed inside the semiconductor wafer, and the semiconductor wafer is divided at the formation site of the modified layer, It is preferable to employ a method.

That is, in the above-described manufacturing method of the semiconductor device, before the laminate structure forming step, a laser beam of an infrared range is irradiated so as to focus on a focal point set inside the semiconductor wafer to form a modified layer inside the semiconductor wafer (Hereinafter referred to as &quot; modified layer forming step &quot; in some cases) and a surface for forming the film-like adhesive in the semiconductor wafer on which the modified layer is formed, (Hereinafter, referred to as &quot; dividing step &quot;) of obtaining a plurality of semiconductor chips by dividing the semiconductor wafer in a region of the modified layer by applying the semiconductor wafer to a plurality of semiconductor It is preferable that the chip is used in the laminated structure forming process.

4 is a cross-sectional view schematically illustrating one embodiment of a method of forming a modified layer on such a semiconductor wafer to obtain a semiconductor chip.

&Lt; Modification layer forming step &

In this modification, as shown in FIG. 4 (a), the semiconductor wafer 8 'is irradiated with an infrared laser beam so as to be converged to a predetermined focal point inside the semiconductor wafer 8' The reformed layer 81 'is formed.

In the modified layer forming step, for example, in order to form the modified layer 81 'while minimizing the damage to the surface or the vicinity of the surface of the semiconductor wafer 8' by laser light irradiation, NA) is large.

<Separation step>

Then, in the dividing step, as shown in Fig. 4 (b), a surface (back surface) 8b 'opposite to the surface (circuit forming surface) 8a' of the semiconductor wafer 8 'is ground . The grinding at this time can be performed in the same manner as the grinding of the back surface of the semiconductor wafer on which the grooves are formed, which has been described with reference to Fig. For example, the grinding of the back surface 8b 'at this time is preferably performed by pasting the back grind tape 63 to the surface 8a' of the semiconductor wafer 8 '.

The rear surface 8b 'of the semiconductor wafer 8' is ground and a force is applied to the semiconductor wafer 8 'during the grinding to grind the modified layer 81' A plurality of semiconductor chips 8 are obtained from the semiconductor wafer 8 ', as shown in Fig. 4 (c), by dividing the semiconductor wafer 8' at the formation site of the semiconductor wafer 8 '. In this case also, the back surface 8b 'of the semiconductor wafer 8' forms the back surface 8b of the semiconductor chip 8, that is, the film-like adhesive 9, similarly to the case described with reference to FIG. .

In any of the above-described methods, when the back grind tape 63 is used, the obtained plurality of semiconductor chips 8 are kept aligned on the back grind tape 63. [

The thickness of the semiconductor chip 8 is not particularly limited, but is preferably 5 to 60 占 퐉, more preferably 10 to 55 占 퐉. When such a thin semiconductor chip is used, the effect when the semiconductor processing sheet of the present invention is used is more remarkably obtained.

In the above-described method of manufacturing a semiconductor device, the film-like adhesive 9 may be any known one, for example, those having curability, preferably having a thermosetting property, and having a pressure-sensitive adhesive property. The film-like adhesive 9 having both a thermosetting property and a pressure-sensitive adhesive property can be attached by lightly pressing on various adherends in an uncured state. The film-like adhesive 9 may be one which can be attached to various adherends by heating and softening. The film-like adhesive 9 becomes a cured product with high impact resistance at the end due to curing, and this cured product can maintain sufficient adhesive properties even under severe high temperature and high humidity conditions.

The thickness of the film-like adhesive 9 is not particularly limited, but is preferably 1 to 50 탆, more preferably 3 to 40 탆. Since the thickness of the adhesive agent 9 on the film is equal to or more than the above lower limit value, a higher adhesion force to the adherend (semiconductor chip) is obtained. In addition, since the thickness of the film-like adhesive 9 is not more than the upper limit value, the film-like adhesive 9 can be more easily cut by the expander described later.

<Cutting Process>

2 (b), the surface 9a of the film-like adhesive 9 is removed while cooling the film-like adhesive 9 of the laminated structure 101, after the step of forming the laminated structure, (9) is stretched in a direction (direction indicated by an arrow I in Fig. 2 (b), that is, a horizontal direction with respect to the surface of the film-like adhesive agent 9) Cut it. The film-like adhesive 9 may be expanded together with the substrate 11 and the pressure-sensitive adhesive layer 12 (i.e., the semiconductor processing sheet 1). Here, the film-like adhesive agent after cutting is indicated by reference numeral 9 '. However, the film-like adhesive agent 9' after such cutting may be simply referred to as "film-like adhesive agent 9 '". The direction of expansion of the film-like adhesive 9 is indicated by the arrow I.

The cooling temperature of the film-like adhesive agent 9 in the cutting step is not particularly limited, but it is preferably -15 to 3 占 폚 in that the film-like adhesive agent 9 can be easily cut.

The expanding speed (expansion speed) of the film-like adhesive 9 in the cutting step is not particularly limited as long as it does not impair the effect of the present invention, but is preferably 0.5 to 100 mm / sec, More preferably 60 mm / sec, and may be, for example, 1 to 50 mm / sec. Since the expand speed falls within this range, the effect of the present invention is more remarkably obtained. Further, when the expand speed is equal to or lower than the upper limit value, the semiconductor chip 8 is less likely to be damaged in the expulsion of the film-like adhesive 9.

Since the semiconductor processing sheet 1 is used in the cutting step, the semiconductor chip 8 having the film-like adhesive 9 'on the back surface 8b after cutting is peeled off from the pressure-sensitive adhesive layer 12 Or scattering is suppressed.

5 is a cross-sectional view schematically showing the state of a semiconductor chip in exposing a film-like adhesive when a conventional semiconductor processing sheet is used.

The pressure-sensitive adhesive layer 72 shown here is conventionally used and when the semiconductor processing sheet 7 formed by forming the pressure-sensitive adhesive layer 72 on the base material 11 is used, the film-like adhesive 9 ' The semiconductor chip 8 having the adhesive layer 72 may be peeled off from the adhesive layer 72 or peeled off from the adhesive layer 72 and scattered. The lifting and scattering of the semiconductor chip on which the film-like adhesive is formed is typically observed when, for example, the above-described pressure-sensitive adhesive layer having a thickness of 200 占 퐉 has a storage elastic modulus at 0 占 폚 of less than 1000 MPa.

Further, lifting and scattering of the semiconductor chip formed with such a film-like adhesive agent is likely to occur when the thickness of the semiconductor chip 8 is thin.

<Separation Process>

2 (c), after the cutting step, the semiconductor chip 8 and the film-like adhesive 9 'after cutting are attached to the semiconductor processing sheet 1 (the pressure-sensitive adhesive layer (12)) and performs pickup.

In the separation step, the semiconductor chip 8 is pulled up by the lifting portion 61 of the semiconductor device manufacturing apparatus, and the film-like adhesive 9 (9 ') Is peeled from the pressure-sensitive adhesive layer (12). The semiconductor chip 8 may be pulled up by a known method. For example, a method of pulling up the surface of the semiconductor chip 8 by a vacuum collet and pulling it up may be mentioned. Here, the pull-up direction of the semiconductor chip 8 is indicated by the arrow II.

Since the semiconductor processing sheet 1 is used in the separating step, the semiconductor chip 8 can be separated from the film-like adhesive 9 'after cutting, and the adhesive layer 9' without cutting the adhesive layer 12, (The semiconductor chip having the film-shaped adhesive formed thereon) can be easily separated from the pressure-sensitive adhesive layer 12 and picked up.

6 is a cross-sectional view schematically showing a state when an attempt is made to pick up a semiconductor chip on which a film-like adhesive is formed when a conventional semiconductor processing sheet is used.

6 (a), when the semiconductor chip 8 is pulled up as in the case of Fig. 2 (c), the film-like adhesive 9 'after the cutting is peeled off from the semiconductor chip 8, The film-like adhesive 9 'is laminated on the pressure-sensitive adhesive layer 72, and only the semiconductor chip 8 is pulled up.

6 (b), when the semiconductor chip 8 is pulled up, the semiconductor chip 8 is bonded to the pressure-sensitive adhesive layer 72 via the film-like adhesive 9 ' , And the semiconductor chip 8 can not be pulled up.

6 (a) and 6 (b) are typically observed when the adhesive force of the pressure-sensitive adhesive layer 72 to the semiconductor wafer is a large value exceeding 200 mN / 25 mm. 6 (a) is likely to occur when the adhesive force of the film-like adhesive 9 'to the semiconductor wafer is relatively small, and the state of Fig. 6 (b) It is likely to occur when the adhesive force to the wafer is a relatively large value.

In the above-described manufacturing method of a semiconductor device, a semiconductor chip 8 (semiconductor chip formed with a film-like adhesive) separated (picked up) together with a film-like adhesive 9 'after cutting is used, Thereby manufacturing a semiconductor device. For example, the semiconductor chip 8 is die-bonded to the circuit surface of the substrate by a film adhesive 9 ', and if necessary, one or more semiconductor chips are further stacked on the semiconductor chip 8 , And after wire bonding, the whole is sealed with a resin to form a semiconductor package (not shown). Then, a desired semiconductor device can be manufactured by using this semiconductor package.

The method for manufacturing a semiconductor device using the semiconductor processing sheet of the present invention is not limited to the above-described method described with reference to Fig. 2, and is not limited within the range that does not hinder the effect of the present invention. Deleted, or added.

The process anomaly described above with reference to Figs. 5 to 6 is an example, and other process anomalies may occur in some cases.

On the other hand, when the semiconductor processing sheet of the present invention is used, occurrence of such processes is suppressed, and as a result, a semiconductor device can be manufactured at a lower cost in a simpler method than the conventional method.

As one aspect of the semiconductor processing sheet according to one embodiment of the present invention,

A sheet for semiconductor processing comprising a pressure-sensitive adhesive layer on a substrate,

Wherein the pressure-sensitive adhesive layer is formed of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin (i) and a crosslinking agent (ii);

The viscous resin (i) is an acrylic polymer having at least a structural unit derived from an alkyl (meth) acrylate, preferably a structural unit derived from 2-ethylhexyl (meth) acrylate, a structural unit derived from 2-hydroxyethyl Acrylic polymer having at least one structural unit selected from the group consisting of structural units derived from 4-hydroxybutyl (meth) acrylate and structural units derived from 4-hydroxybutyl (meth) acrylate;

The crosslinking agent (ii) is an isocyanate-based crosslinking agent, preferably a tolylene diisocyanate trimer adduct of trimethylolpropane;

The content of the adhesive resin (i) is preferably 45 to 90 mass%, more preferably 55 to 87 mass%, more preferably 65 to 84 mass%, and particularly preferably 72 to 81 mass%, based on the total mass of the pressure- Mass%;

The content of the crosslinking agent (ii) is preferably 5 to 50 parts by mass, preferably 10 to 45 parts by mass, more preferably 15 to 40 parts by mass, particularly preferably 20 to 50 parts by mass with respect to 100 parts by mass of the content of the viscous resin (i) Is 22 to 38 parts by mass;

When the thickness of the pressure-sensitive adhesive layer is 200 占 퐉, the pressure-sensitive adhesive layer having a thickness of 200 占 퐉 has a storage elastic modulus at 0 占 폚 of 100 MPa to 1000 MPa, preferably 300 MPa to 1000 MPa, more preferably 500 MPa to 996 MPa, Is 533 MPa to 999 MPa;

When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive strength of the pressure-sensitive adhesive layer to the mirror surface is 10 to 200 mN / 25 mm, preferably 30 to 200 mN / 25 mm, more preferably 50 to 196 mN / 25 mm, and particularly preferably 55 to 194 mN / 25 mm.

In another aspect of the semiconductor processing sheet which is one embodiment of the present invention,

A sheet for semiconductor processing comprising a pressure-sensitive adhesive layer on a substrate,

Wherein the pressure-sensitive adhesive layer is formed of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin (i) and a crosslinking agent (ii);

Wherein the viscous resin (i) is an acrylic polymer having at least one structural unit selected from the group consisting of a structural unit derived from 2-ethylhexyl (meth) acrylate and a structural unit derived from 2-hydroxyethyl (meth) acrylate;

Wherein said crosslinking agent (ii) is a tolylene diisocyanate trimer adduct of trimethylolpropane;

The content of the viscous resin (i) is 76 to 81 mass%;

The content of the crosslinking agent (ii) is 22 to 31 parts by mass based on 100 parts by mass of the content of the viscous resin (i);

The storage elastic modulus at 0 占 폚 of the pressure-sensitive adhesive layer having the thickness of 200 占 퐉 is 533 MPa to 873 MPa when the thickness of the pressure-sensitive adhesive layer is 200 占 퐉;

And the adhesive strength of the pressure-sensitive adhesive layer to the mirror surface is 94 to 194 mN / 25 mm when the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer.

In another aspect of the semiconductor processing sheet which is one embodiment of the present invention,

A sheet for semiconductor processing comprising a pressure-sensitive adhesive layer on a substrate,

Wherein the pressure-sensitive adhesive layer is formed of a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive resin (i) and a crosslinking agent (ii);

The adhesive resin (i) is an acrylic polymer having at least one constituent unit selected from the group consisting of a constituent unit derived from 2-ethylhexyl (meth) acrylate and a constituent unit derived from 4-hydroxybutyl (meth) acrylate;

Wherein said crosslinking agent (ii) is a tolylene diisocyanate trimer adduct of trimethylolpropane;

The content of the viscous resin (i) is 70 to 75 mass%;

The content of the crosslinking agent (ii) is 35 to 39 parts by mass based on 100 parts by mass of the content of the adhesive resin (i);

Wherein the pressure-sensitive adhesive layer having a thickness of 200 占 퐉 has a storage elastic modulus at 0 占 폚 of 500 MPa to 994 MPa, when the thickness of the pressure-sensitive adhesive layer is 200 占 퐉;

When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive force of the pressure-sensitive adhesive layer to the mirror surface is 50 to 60 mN / 25 mm.

Example

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

On the other hand, in the following, time unit "msec" means "millisecond".

The components used in the production of the pressure-sensitive adhesive composition are shown below.

· Adhesive resin

(80 parts by mass) (hereinafter abbreviated as &quot; 2EHA &quot;) and 2-hydroxyethyl acrylate (hereinafter abbreviated as &quot; HEA &quot; (Weight-average molecular weight: 860,000, glass transition temperature: -61 ° C).

Acrylic polymer (weight average molecular weight: 430000) obtained by copolymerizing a viscous resin (i) -2: 2 EHA (80 parts by mass) and 4-hydroxybutyl acrylate (hereinafter abbreviated as "4 HBA" , Glass transition temperature-63 캜).

Acrylic polymer obtained by copolymerizing a viscous resin (i) -3: 2 EHA (60 parts by mass), methyl methacrylate (hereinafter abbreviated as "MMA") (30 parts by mass) and HEA (10 parts by mass) Average molecular weight 430000, glass transition temperature -31 占 폚).

(Weight-average molecular weight: 7,20000, glass transition temperature -20 ° C) obtained by copolymerizing a viscous resin (i) -4: lauryl acrylate (hereinafter abbreviated as LA) (80 parts by mass) and HEA 27 C).

· Cross-linking agent

Cross-linking agent (ii) -1: Tolylene diisocyanate trimeric adduct of trimethylolpropane ("Coronate L" manufactured by Tosoh Corporation)

· Photopolymerization initiator

Photopolymerization initiator (iii) -1: 1-Hydroxycyclohexyl phenyl ketone ("Irgacure (registered trademark) 184"

[Example 1]

&Lt; Production of sheet for semiconductor processing &

(Preparation of pressure-sensitive adhesive composition)

(Ii) -1 (30.16 parts by mass) was added to the viscous resin (i) -1 (100 parts by mass) and the mixture was stirred at 23 占 폚 to obtain a specific energy ray curable pressure-sensitive adhesive composition.

On the other hand, the number of components shown here is a solid content conversion value.

Table 1 shows the blending components and their blending amounts. On the other hand, the description of "-" in the mixture component column in Table 1 means that the components are unmixed.

(Production of sheet for semiconductor processing)

The pressure-sensitive adhesive composition obtained above was coated on the release surface of a release film ("SP-PET381031" manufactured by Linx Co., Ltd., thickness 38 탆) having one surface of the polyethylene terephthalate film peeled off by silicone treatment, Followed by heating and drying for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 10 mu m.

Subsequently, a film made of a low-density polyethylene (LDPE) having a thickness of 110 占 퐉 as a substrate was applied to the exposed surface of the pressure-sensitive adhesive layer to obtain a semiconductor processing sheet having a release film.

&Lt; Evaluation of sheet for semiconductor processing &

(An effect of suppressing lifting and scattering of a semiconductor chip on which a film adhesive is formed)

(DFD6361 &quot; manufactured by Disco Co., Ltd.) was used, and a square having a size of 10 mm x 10 mm was formed on the mirror surface of an 8-inch silicon wafer (thickness 720 m) And the half-cut dicing was performed to form the groove by inserting the sheath by the dicing blade. At this time, "27HECC" manufactured by DISCO Corporation was used as the dicing blade, and the moving speed of the dicing blade was 50 mm / sec and the rotation speed was 40000 rpm.

Subsequently, a back grind tape ("ADWILL E-3125KN" manufactured by Lin Tec Co., Ltd.) was applied to the mirror surface of the silicon wafer on which the grooves were formed at room temperature (23 ° C) using a tape laminator (RAD- ) Was pasted by the adhesive layer.

Then, a grinder ("DFG8760" manufactured by DISCO Corporation) was used and the surface of the silicon wafer opposite to the mirror surface on which the grooves were formed was ground. At this time, grinding was performed so that the thickness of the silicon wafer became 50 占 퐉, and at the same time, the silicon wafer was divided into silicon chips. The obtained silicon chips were fixed on the back grind tape at intervals of about 30 mu m.

Subsequently, a film-like adhesive ("ADWILL LE61-25 *" manufactured by Lin Tec Co., Ltd., thickness 25 μm) heated to 60 ° C was attached to the grinding surface of the obtained silicon chip, and furthermore, The working sheet was pasted with the pressure-sensitive adhesive layer at room temperature (23 占 폚) to obtain a laminate.

Next, the obtained laminate is attached and fixed to the dicing ring frame by the exposed surface of the pressure-sensitive adhesive layer, and the back grind tape is peeled off from the silicon chip to form a pressure-sensitive adhesive layer , A test piece of a laminated structure in which a film-like adhesive agent was laminated, and a plurality of semiconductor chips previously unified in advance were arrayed and formed on the film-like adhesive.

(Expanded amount) of 10 mm and an expanded speed (expansion rate) of 10 mm / min were set under the environment of 0 占 폚 in the expanded unit of the expander (ME-300B, manufactured by JCM) sec, the semiconductor processing sheet and the film-like adhesive agent were extruded, and the film-like adhesive agent was cut along the outline of the silicon chip. That is, the semiconductor processing sheet obtained above was used as an expanding sheet.

Subsequently, with respect to a silicon chip (a semiconductor chip on which a film-form adhesive agent was formed) provided with a film-like adhesive agent, which had been cut off visually, whether or not lifted from the pressure-sensitive adhesive layer and scattering were observed was observed. (A), the inhibitory effect of the excitation / scattering was judged to be rejection (B) when any abnormality was observed. The results are shown in the column of &quot; suppression of lifting and scattering of semiconductor chips &quot;

(Pick-up suitability of a semiconductor chip on which a film-like adhesive is formed)

The above-mentioned &quot; effect of suppressing lifting and scattering of a semiconductor chip on which a film-form adhesive was formed &quot; was evaluated using a pickup-die bonding apparatus (BESTEM D02, manufactured by Canon Machinery Inc.) The semiconductor chip having the adhesive formed thereon was picked up 30 times by a one-pin pressing method under the conditions of a pressing amount of 200 mu m, a pressing speed of 20 mm / sec, and a lifting holding time of 300 msec. If the pickup is successful all 30 times, the pick-up suitability is judged as pass (A). If the pick-up fails more than once, the pick-up suitability is judged as fail (B). The results are shown in the column of &quot; pick-up suitability &quot;

(Storage elastic modulus of the laminate composed of the pressure-sensitive adhesive layer)

Using the sheet for semiconductor processing thus obtained, a multilayer body in which a plurality of pressure-sensitive adhesive layers on which a substrate was peeled off was laminated so as to have a total thickness of 200 mu m was produced. Then, using a dynamic viscoelasticity measuring apparatus ("DMA Q800" manufactured by TA Instruments Co., Ltd.), under the conditions of a heating rate of 10 ° C./min, a frequency of 11 Hz, and a temperature of -50 to 50 ° C., The elastic modulus (MPa) was measured. The results are shown in the column of &quot; storage elastic modulus &quot;

(Adhesive force of the pressure-sensitive adhesive layer)

The semiconductor processing sheet obtained above was cut into a size of 25 mm x 150 mm and attached to the mirror surface of the silicon wafer by the pressure sensitive adhesive layer at room temperature (23 캜). Then, the semiconductor processing sheet was peeled at a peeling speed of 300 mm / min so that the surfaces of the pressure-sensitive adhesive layer and the silicon wafer contacting each other at an angle of 180 deg. With this temperature condition, Was measured, and the measured value was regarded as an adhesive force (mN / 25 mm). The results are shown in the column of "Adhesion" in Table 1.

[Examples 2 to 4, Comparative Examples 1 to 3]

<Production and Evaluation of Sheet for Semiconductor Processing>

A sheet for semiconductor processing was produced and evaluated in the same manner as in Example 1, except that the blending components and the blending amount thereof in the production of the pressure-sensitive adhesive composition were changed as shown in Table 1. [ The results are shown in Table 1.

On the other hand, the pressure-sensitive adhesive layer in Comparative Example 3 had energy ray (ultraviolet ray) curability as is apparent from the components contained in the pressure-sensitive adhesive composition. However, during the period from the formation of the pressure- No curing was carried out.

As apparent from the above results, in Examples 1 to 4, the storage elastic modulus of the laminate at 0 캜 was 994 MPa or less, and at the time of cutting by expanding the film-like adhesive, Lifting and scattering from the pressure-sensitive adhesive layer were completely suppressed. Further, the adhesive force of the pressure-sensitive adhesive layer to the semiconductor wafer was 194 mN / 25 mm or less, and the pickup performance of the semiconductor chip on which the film-like adhesive was formed was excellent even without curing by energy ray irradiation or the like.

On the other hand, in Comparative Examples 1 and 2, the storage elastic modulus of the laminate at 0 占 폚 was 1218 MPa or more, and lifting and scattering of the semiconductor chip on which the film-like adhesive was formed were not suppressed.

In Comparative Example 3, the adhesive force of the pressure-sensitive adhesive layer to the semiconductor wafer was as large as 534 mN / 25 mm, and the pick-up suitability of the semiconductor chip on which the film-like adhesive was formed was poor.

On the other hand, a silicone chip obtained by dicing a half-cut dicing of a silicon wafer is used in the evaluation of the above-described effect of suppressing the lifting and scattering described above. However, instead of the method of forming grooves in such a silicon wafer, the same evaluation results can be obtained by using a silicon chip obtained by employing, for example, a method of forming a modified layer in the semiconductor wafer (silicon wafer). This is because, if there is no abnormality in the semiconductor chip used for the evaluation, the semiconductor chip manufacturing method (semiconductor wafer dividing method) does not affect the evaluation process.

The present invention is industrially very useful because it can be used for manufacturing semiconductor devices.

One… Sheet for semiconductor processing, 11 ... 11a ... The surface of the substrate, 12 ... A pressure-sensitive adhesive layer, 12a ... The surface of the pressure-sensitive adhesive layer, 8 ... Semiconductor chip, 8b ... The back side of the semiconductor chip

Claims (3)

A semiconductor processing sheet having a pressure-sensitive adhesive layer on a substrate and having the following characteristics:
Wherein the pressure-sensitive adhesive layer having a thickness of 200 mu m has a storage elastic modulus at 0 deg. C of 1000 MPa or less, when the thickness of the pressure-sensitive adhesive layer is 200 mu m,
When the semiconductor processing sheet is attached to the mirror surface of the semiconductor wafer, the adhesive force of the pressure sensitive adhesive layer to the mirror surface is 200 mN / 25 mm or less. The method according to claim 1,
Wherein the pressure-sensitive adhesive layer is non-energy radiation curable. 3. The method according to claim 1 or 2,
And a film adhesive is further provided on the pressure-sensitive adhesive layer.

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