TW202018033A - Resin composition for dicing film substrate, dicing film substrate, and dicing film - Google Patents

Abstract

The purpose of the present invention is to provide a resin composition for a dicing film substrate for producing a dicing film having both high strength and high thermal shrinkage. Provided are: a resin composition for a dicing film substrate, the resin composition containing 30-90 parts by mass of an ionomer (A) of an ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer and 10-70 parts by mass of an ethylene copolymer (B) (with respect to 100 parts by mass in total of component (A) and component (B)), and having a Vicat softening point of less than 50 DEG C as defined according to JIS K7206-1999; a dicing film substrate using the resin composition; and a dicing film using the resin composition.

Description

Resin composition for cutting film base material, cutting film base material and cutting film

The present invention relates to a resin composition for a dicing film base material, and a dicing film base material and a dicing film using the same.

In the manufacturing process of semiconductor devices such as integrated circuits (ICs), generally, a semiconductor wafer formed with a circuit pattern is thinned, and then a dicing step for dividing the semiconductor wafer into chip units is performed. In the dicing step, the flexible wafer processing film (called dicing film or dicing tape) is attached to the back of the semiconductor wafer, and then the semiconductor wafer is divided into chip units by a dicing knife or laser . Then, in the next expansion step (also referred to as an extension step), the dicing tape corresponding to the cut wafer is expanded, and the chip is converted into a wafer.

In the stretching step, for example, the cutting film is expanded (stretched) by jacking up an expansion table provided under the cutting film. At this time, in order to divide the wafer, it is important that the dicing film is uniformly expanded on the entire surface of the expansion table. In addition, since the stress applied to the cutting film at the peripheral edge portion of the expansion table is greater than the central portion of the expansion table, the portion of the cutting film after the expansion step corresponding to the peripheral edge portion of the expansion table is slack. Such slack will make the interval of the divided wafers non-uniform, which may be the cause of defective products in subsequent steps.

As a means to eliminate the slack of the cut film, a heat shrinking step is known, that is, by blowing hot air with an actual temperature of about 80 to 100°C on the slack portion of the film to add Heat shrinks it and restores it to its original state (for example, refer to Patent Document 1). In order to implement this step, the dicing film needs to have high heat shrinkage at a temperature of about 80°C.

In addition, the cutting method that has attracted much attention in recent years is the stealth cutting (registered trademark) method. In this method, laser light is used to form cracks inside the wafer rather than on the surface, and the next expansion step is performed at a low temperature (about -15 °C ~ 0 °C), using the stress of the dicing film to split the wafer . By this, the loss of the semiconductor product in the dicing step can be suppressed, thereby improving the yield. As the dicing film used here, it is required to have both the strength capable of withstanding the stress required for wafer division and the heat shrinkability for eliminating the slack that may be generated during wafer division in the heat shrinking step.

As a substrate for a dicing film used for a dicing film, a dicing film substrate containing an ionic polymer obtained by crosslinking a compound having a carboxyl group by cations and an octene-containing copolymer is known (Patent Document 2) ; The lowest layer containing a thermoplastic resin containing a Fika softening point specified by JIS K7206 of 80°C or more, and other layers containing a thermoplastic resin having a Fika softening point specified by JIS K7206 of 50°C or more and less than 80°C A dicing film base material (Patent Document 3); and a dicing film base material containing a thermoplastic resin having a Fika softening point defined by JIS K7206 of 50°C or more and less than 90°C (Patent Document 4).

In addition, Patent Document 5 discloses a dicing film which is suitable for stealth cutting (registered trademark) and has excellent expandability. The initial elastic modulus at -10°C is 200 MPa or more and 380 MPa or less, Tan δ (loss elastic modulus/storage elastic modulus) is 0.080 or more and 0.3 or less.

[Prior Technical Literature] [Patent Literature]

[Patent Literature 1] Japanese Patent Laid-Open No. 9-007976

[Patent Document 2] Japanese Patent Laid-Open No. 2000-345129

[Patent Document 3] Japanese Patent Laid-Open No. 2009-231700

[Patent Document 4] Japanese Patent Laid-Open No. 2011-216508

[Patent Document 5] Japanese Patent Laid-Open No. 2015-185591

In Patent Document 1, as a dicing film capable of removing slack by a heat shrinking step, for example, a ternary polymer including an ionic polymer having a melting point of 71°C (polymerizing acrylate or methacrylate, etc.) is described. Ionic polymer) and a cut film of a layer formed by a blend of ethylene-vinyl acetate copolymer. However, there is no record of the basic properties required for the cutting film such as the expandability or strength of the cutting film.

In Patent Document 2, as a specific example of a substrate for a dicing film, a substrate for a dicing film containing a ternary copolymer plasma polymer containing ethylene/methacrylic acid/acrylate and an octene-containing copolymer is described. However, there is no description about the heat shrinkage of the dicing film.

According to the studies of the present inventors and others, it is considered that the dicing film substrate of Patent Document 3 having a layer containing a thermoplastic resin having a Fika softening point of 80°C or higher, or containing a Fika softening point of 50°C or higher and less than 90°C The heat-shrinkability of the dicing film base material of Patent Document 4 of the thermoplastic resin at 80°C is low, and it is difficult to restore the relaxation to the original state through the heat shrinking step.

In addition, Patent Document 5 describes a dicing film having a base material containing an ionic polymer of an ethylene-α-olefin copolymer or an ethylene-α-olefin copolymer. However, there is no description about a substrate for a dicing film that contains an ionic polymer or a ternary or more ternary multi-component copolymer containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester or the like. The resin composition of the multi-component copolymer and the ethylene-based copolymer.

The present invention has been completed in view of the problems of the above-mentioned conventional technology, and its object is to provide a resin composition for a dicing film base material for manufacturing a dicing film having both high strength and high heat shrinkability. Furthermore, the subject of this invention is providing the dicing film base material and dicing film using the resin composition for dicing film base materials of this invention.

That is, according to the present invention, the following resin composition for a dicing film base material, dicing film base material, and dicing film are provided.

[1] A resin composition for a dicing film base material, comprising: an ionic polymer (A) of an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of 30 parts by mass or more and 90 parts by mass or less, and an ethylene-based The copolymer (B) is 10 parts by mass or more and 70 parts by mass or less (wherein the total of the component (A) and the component (B) is set to 100 parts by mass), and the Fika softening point prescribed by JIS K7206-1999 is less than 50℃.

[2] The resin composition for a dicing film base material according to [1], wherein the above-mentioned ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer ionic polymer (A) phenanthrene as specified in JIS K7206-1999 The card softening point is above 25°C and below 60°C.

[3] The resin composition for a dicing film base material as described in [1] or [2], wherein the ethylene-based copolymer (B) is a resin with a Fika softening point defined by JIS K7206-1999 of 50°C or less, Or resins without the above-mentioned Fika softening point.

[4] The resin composition for a dicing film base material according to any one of [1] to [3], wherein The above-mentioned ethylene-based copolymer (B) is at least one selected from the group consisting of an ethylene-α-olefin copolymer and an ethylene-unsaturated carboxylic acid ester copolymer.

[5] The resin composition for a dicing film base material according to any one of [1] to [4], wherein the above ethylene-based copolymer is measured by a method according to JIS K7210-1999 at 190°C under a load of 2160 g The melt flow rate (MFR) of the combination (B) is 0.2 g/10 minutes to 30.0 g/10 minutes.

[6] The resin composition for a dicing film substrate according to any one of [1] to [5], wherein the dicing film base is measured by a method according to JIS K7210-1999 at 190°C under a load of 2160 g The melt flow rate (MFR) of the resin composition for wood is 0.1 g/10 minutes to 50 g/10 minutes.

[7] A dicing film base material comprising at least one layer containing the resin composition for a dicing film base material according to any one of [1] to [6].

[8] The dicing film base material according to [7], comprising: a first resin layer including the resin composition for a dicing film base material according to any one of [1] to [6], and a layer deposited on the above The second resin layer containing the resin (C) in the first resin layer.

[9] The dicing film substrate according to [8], wherein the resin (C) is a group composed of an ionic polymer of an ethylene-unsaturated carboxylic acid copolymer and the ethylene-unsaturated carboxylic acid copolymer At least one group selection.

[10] A dicing film comprising the dicing film base material according to any one of [7] to [9], and an adhesive layer laminated on at least one side of the dicing film base material.

The invention provides a resin composition for a dicing film base material for manufacturing a dicing film having both high strength and high heat shrinkability, and a dicing film base material and a dicing film using the same.

1‧‧‧The first resin layer

2‧‧‧The second resin layer

10‧‧‧Cut film base material

11‧‧‧ Adhesive layer

20‧‧‧Cutting film

FIG. 1A is a cross-sectional view showing an embodiment of a dicing film substrate of the present invention.

1B is a cross-sectional view showing an embodiment of the dicing film substrate of the present invention.

2A is a cross-sectional view showing an embodiment of the dicing film of the present invention.

2B is a cross-sectional view showing an embodiment of the dicing film of the present invention.

Hereinafter, the resin composition for a dicing film base material of the present invention will be described in detail, and the dicing film base material and the dicing film will also be described in detail.

In addition, in this specification, the notation of "~" indicating the numerical range includes the meaning of the lower limit value and the upper limit value of the numerical range.

In addition, "(meth)acrylic acid" includes the notation used by both "acrylic acid" and "methacrylic acid", and "(meth)acrylate" includes the use of both "acrylate" and "methacrylate" Notation.

In the manufacturing process of semiconductor wafers, the dicing film needs to have a high heat shrinkability at a temperature near 80°C to use the thermal contraction of the film to eliminate the slack of the dicing film after the expansion (extension) step (revert to the original State). In the present invention, by using the following resin composition to manufacture a dicing film base material, a dicing film having both high strength and high heat shrinkability can be manufactured. The resin composition includes ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid The ionic polymer (A) of the ester copolymer is 30 parts by mass or more and 90 parts by mass or less, and the ethylene-based copolymer (B) is 10 parts by mass or more and 70 parts by mass or less (wherein, the component (A) and the component (B) The total is 100 parts by mass). Although the mechanism is not clear, it can be considered as follows.

It is known to improve the polyolefin resin by blending an ethylene copolymer High heat shrinkage. However, if a resin composition containing a polyolefin-based resin and an ethylene-based copolymer is used to produce a film, the strength and expandability of the film are insufficient as a dicing film. On the other hand, in the present invention, by using an ionic polymer of an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer and an ethylene-based copolymer to produce a resin composition having a Fica softening point of less than 50°C, A cut film with improved heat shrinkability without greatly reducing the film strength or expansibility (dividability) of the ionic cross-linked structure derived from the ionic polymer.

The dicing film of the present invention can be preferably used for a method of manufacturing a semiconductor device that not only implements a dicing step and an expansion step for dividing a semiconductor wafer into wafer units, but also performs a heat shrinking step. In particular, since the cutting film of the present invention has both high strength and high heat shrinkage, it can be preferably used for applying the conventional method (blade cutting method or laser ablation method, etc.) to the cutting film in the expansion step Manufacturing method of invisible cutting (registered trademark) method of large stress. By using the dicing film of the present invention, the interval of the divided wafers can be made uniform, and the product defects in the subsequent steps can be reduced, so that the semiconductor device can be manufactured with higher yield.

Hereinafter, the present invention will be described by way of exemplary embodiments, but the present invention is not limited to the following embodiments.

1. Resin composition for cutting film substrate

The first aspect of the present invention is a resin composition for a dicing film base material. The resin composition for a dicing film base material contains: an ionic polymer (A) of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of 30 parts by mass or more and 90 parts by mass or less, and an ethylene-based copolymer (B) 10 Not less than 70 parts by mass (the total of component (A) and component (B) is set to 100 parts by mass).

1-1. Resin (A)

Ionic polymer of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer used as resin (A) (hereinafter, also referred to simply as "ionic polymer (A)") is an ethylene-unsaturated carboxylic acid-not A part or all of the carboxyl group of the saturated carboxylate copolymer is obtained by neutralizing the metal (ion). In the present invention, those in which at least a part of the acid groups of the copolymer are neutralized with metals (ions) are called "ionic polymers", and those in which the acid groups of the copolymers are not neutralized with metals (ions) are called "copolymers" ".

The ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymerization system constituting the above-mentioned ionic polymer (A) is an at least ternary copolymer obtained by copolymerizing ethylene with an unsaturated carboxylic acid and an unsaturated carboxylic acid ester, or It is a quaternary or more multi-component copolymer obtained by copolymerization with the fourth copolymerization component. Furthermore, one ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer may be used alone, or two or more ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers may be used in combination.

Examples of the unsaturated carboxylic acid constituting the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, Unsaturated carboxylic acids with 4 to 8 carbon atoms, such as crotonic acid, maleic acid, maleic anhydride, etc. Particularly preferred is acrylic acid or methacrylic acid.

The unsaturated carboxylic acid ester constituting the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is preferably an unsaturated carboxylic acid alkyl ester. The carbon number of the alkyl portion of the alkyl ester is preferably from 1 to 12, more preferably from 1 to 8, and even more preferably from 1 to 4. Examples of the alkyl moiety include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, 2-ethylhexyl, and isooctyl. Specific examples of unsaturated carboxylic acid alkyl esters include methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, Alkyl (meth)acrylates such as isooctyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, dimethyl maleate, diethyl maleate .

When the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is a quaternary or more multicomponent copolymer, a monomer (fourth copolymerization component) that forms a multicomponent copolymer may also be included. Examples of the fourth copolymerization component include unsaturated hydrocarbons (for example, propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), vinyl esters ( For example, vinyl acetate, vinyl propionate, etc.), oxides of vinyl sulfuric acid or vinyl nitric acid, halogen compounds (eg, vinyl chloride, vinyl fluoride, etc.), vinyl-containing first/secondary amine compounds, carbon monoxide , Sulfur dioxide, etc.

The form of the copolymer may be any of a block copolymer, a random copolymer, and a graft copolymer, and may also be any of a ternary copolymer or a quaternary multi-component copolymer. Among them, in terms of industrial availability, a ternary random copolymer or a graft copolymer of a ternary random copolymer is preferred, and a ternary random copolymer is more preferred.

Specific examples of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer include ternary copolymers such as ethylene-methacrylic acid-butyl acrylate copolymer.

When the total amount of constituent units constituting the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 100% by mass, the unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is derived from The content ratio of the constituent units is preferably 4% by mass or more and 20% by mass or less, and more preferably 5% by mass or more and 15% by mass or less. When the total amount of the constituent units constituting the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 100% by mass, the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer comes out The content ratio of the constituent units of the unsaturated carboxylic acid ester is preferably 1% by mass or more and 20% by mass or less, more preferably 5% by mass or more and 18% by mass or less, and particularly preferably 5% by mass or more and 17% by mass or less . From the viewpoint of the expandability of the membrane, the content ratio of the structural unit derived from the unsaturated carboxylic acid ester is preferably 1% by mass or more, and preferably 5% by mass or more. In addition, from the viewpoint of preventing blocking and fusion, the content ratio of the structural unit derived from the unsaturated carboxylic acid ester is preferably 20% by mass or less, more preferably 18% by mass or less, and particularly preferably 17% by mass or less.

In the present invention, the ionic polymer (A) used as the resin (A) is preferably the carboxyl group contained in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, which is crosslinked by metal ions at an arbitrary ratio (Neutralization) income. Examples of the metal ion used in the neutralization of the acid group include metal ions such as lithium ion, sodium ion, potassium ion, rubidium ion, cesium ion, zinc ion, magnesium ion, and manganese ion. Among these metal ions, in terms of the availability of industrial products, magnesium ions, sodium ions and zinc ions are preferred, sodium ions and zinc ions are more preferred, and zinc ions are particularly preferred.

One metal ion may be used alone, or two or more may be used in combination.

The degree of neutralization of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer in the ionic polymer (A) (hereinafter, also referred to as "the degree of neutralization of the ionic polymer (A)") is not particularly limited, It is preferably 10% to 100%, and more preferably 30% to 100%. If the degree of neutralization is within the above range, the film strength or splittability is improved, which is preferable.

Furthermore, the degree of neutralization of the ionic polymer (A) is the ratio of the number of moles of carboxyl groups neutralized by metal ions to the total number of carboxyl groups contained in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer (( Mohr%).

As the ionic polymer (A) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, commercially available products can be used. Examples of commercially available products include: Dow-Mitsui Polychemicals Co., Ltd.'s Himilan (registered trademark) series, etc.

The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester ionomer (A) is preferably in the range of 0.2 g/10 minutes to 20.0 g/10 minutes, more preferably 0.5 g/10 Minutes to 20.0 g/10 minutes, and further preferably 0.5 g/10 minutes to 18.0 g/10 minutes. If the melt flow rate is within the above range, it is advantageous when forming a film.

In addition, MFR is the value measured by the method based on JIS K7210-1999 at 190 degreeC and a load of 2160g.

Furthermore, the Fica softening point of the ionic polymer (A) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester is preferably 25°C or higher and 60°C or lower, and more preferably 35°C or higher and 60°C or lower. If the Fika softening point of the ionic polymer (A) is within the above range, it is easy to adjust the Fika softening point of the resin composition to less than 50°C.

In addition, the Fika softening point is a value measured according to the A50 method specified in JIS K7206-1999.

The content of the resin (A) in the resin composition for a dicing film base material of the present invention is 30 parts by mass or more and 90 parts by mass or less with respect to the total of 100 parts by mass of the resin (A) and the following resin (B). It is preferably 40 parts by mass or more and 90 parts by mass or less, and more preferably 50 parts by mass or more and 70 parts by mass or less. If the content of the resin (A) is 30 parts by mass or more, sufficient strength as a dicing film can be obtained, and if it is 90 parts by mass or less, the heat shrinkage rate can be improved.

1-2. Resin (B)

The ethylene-based copolymer (B) (hereinafter, also simply referred to as "copolymer (B)") used as the resin (B) is a copolymer of ethylene and other monomers, and the type thereof is not particularly limited. However, it is important that when the resin composition is prepared together with the above-mentioned ionic polymer (A), the ionic polymer (A) and the interpolymer (B) are added if the composition has a Fika softening point of less than 50°C. combination. From such a viewpoint, the copolymer (B) is preferably a resin having a Fica softening point of 50° C. or lower, or a resin having no Fica softening point. In addition, when the copolymer (B) has a Fica softening point, from the viewpoint of processability, the Fica softening point is preferably 25° C. or higher.

In addition, the Fika softening point is a value measured according to the A50 method specified in JIS K7206-1999.

Examples of the ethylene-based copolymer (B) used in the present invention include ethylene-α-olefin copolymers, ethylene-unsaturated carboxylic acid ester copolymers, and ethylene-vinyl ester copolymers, and preferably ethylene -a olefin copolymer and ethylene-unsaturated carboxylate copolymer.

Ethylene-α-olefin copolymerization system Copolymer of ethylene and α-olefin. This copolymer may contain only one kind of α-olefin, or two or more kinds. Specific examples of α-olefins include: propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, 3- Methyl-1-pentene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, etc. Among them, in terms of availability, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferred. Furthermore, the ethylene-α-olefin copolymer may be a random copolymer or a block copolymer, preferably a random copolymer.

The content ratio of constituent units derived from ethylene contained in the ethylene-α-olefin copolymer is not particularly limited, but it is preferably more than 50 mol% and 95 mol% or less, and more preferably 70 mol% or more and 94 mol% or less. The proportion of constituent units derived from α-olefins (hereinafter, also referred to as “α-olefin units”) contained in the ethylene-α-olefin copolymer is preferably 5 mol% or more and less than 50 mol%, more preferably 6 mol% Above and 30mol% under. Such an ethylene-α-olefin copolymer is advantageous for ensuring shrinkage.

As the ethylene-olefin copolymer -α- body, preferably a density of 895kg / m ³ or less, particularly 860 ~ 890kg / m ³ persons.

Ethylene-unsaturated carboxylic acid ester copolymerization system. Copolymer of ethylene and unsaturated carboxylic acid ester. The copolymer may contain only one type of unsaturated carboxylic acid ester structural unit, or two or more types. Examples of the unsaturated carboxylic acid constituting the constituent unit of the unsaturated carboxylic acid ester include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid and maleic acid Dicarboxylic acid, maleic anhydride and other unsaturated carboxylic acids with 4-8 carbon atoms. Particularly preferred is acrylic acid or methacrylic acid.

Furthermore, the unsaturated carboxylic acid ester constituent unit contained in the ethylene-unsaturated carboxylic acid ester copolymer is preferably an unsaturated carboxylic acid alkyl ester. The carbon number of the alkyl portion of the alkyl ester is preferably from 1 to 12, more preferably from 1 to 8, and even more preferably from 1 to 4. Examples of the alkyl moiety include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, 2-ethylhexyl, and isooctyl. Specific examples of unsaturated carboxylic acid alkyl esters include methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, Alkyl (meth)acrylates such as isobutyl methacrylate, dimethyl maleate, and diethyl maleate.

When the total amount of the constituent units constituting the ethylene-unsaturated carboxylic acid ester copolymer is 100% by mass, the content ratio of the constituent units derived from the unsaturated carboxylic acid ester in the ethylene-unsaturated carboxylic acid ester copolymer is preferably 5 mass% or more and 40 mass% or less, more preferably 7 mass% or more and 40 mass% or less, particularly preferably 8 mass% or more and 40 mass% or less. If the content ratio of the structural unit derived from an unsaturated carboxylic acid ester is below the above upper limit, it is preferable from the viewpoint of film processability. Also, if it comes from unsaturated carboxyl The content ratio of the structural unit of an acid ester is more than the said lower limit, It is preferable from a viewpoint of shrinkage.

The melt flow rate (MFR) of the ethylene-based copolymer (B) is preferably in the range of 0.2 g/10 minutes to 30.0 g/10 minutes, and more preferably 0.5 g/10 minutes to 25.0 g/10 minutes. When the melt flow rate is within the above range, it is advantageous when molding the resin composition.

In addition, MFR is the value measured by the method based on JIS K7210-1999 at 190 degreeC and a load of 2160g.

Furthermore, the melting point of the ethylene-based copolymer (B) is preferably 30°C or higher and 100°C or lower, more preferably 30°C or higher and 80°C or lower.

In addition, the melting point is the melting temperature measured by a differential scanning calorimeter (DSC) according to JIS-K7121 (1987).

The content of the resin (B) in the resin composition for a dicing film base material is 10 parts by mass or more and less than 70 parts by mass relative to the total of 100 parts by mass of the resin (A) and the resin (B), preferably 10 parts by mass It is more than 60 parts by mass and more preferably 20 parts by mass or more and 50 parts by mass or less. If the content of the resin (B) is 10 parts by mass or more, the effect of improving the heat shrinkage rate by the resin (B) is exerted, and if it is less than 70 parts by mass, there is less concern that the strength of the dicing film substrate becomes insufficient .

1-3. Other polymers and additives

It is also possible to add other polymers or various additives to the resin composition for dicing film base materials within the range that does not impair the effects of the present invention. Examples of other polymers include polyamidoamines, polyurethanes, and ionic polymers of binary copolymers. Such other polymers can be formulated in a ratio of, for example, 20 parts by mass or less with respect to a total of 100 parts by mass of resin (A) and resin (B). As an example of additives, there can be cited: Antistatic agent, antioxidant, heat stabilizer, light stabilizer, ultraviolet absorber, pigment, dye, slip agent, anti-blocking agent, antistatic agent, mildew inhibitor, antibacterial agent, flame retardant, flame retardant aid , Crosslinking agent, crosslinking aid, foaming agent, foaming aid, inorganic filler, fiber reinforced materials, etc.

1-4. Physical properties of resin composition

The resin composition of the present invention has a Fica softening point defined by JIS K7206-1999 of less than 50°C, preferably 25°C or more and less than 50°C. If the Fica softening point of the resin composition is less than 50°C, the thermal shrinkage rate increases, and if it is 25°C or higher, the resin composition can be processed into a film.

The melt flow rate (MFR) of the resin composition of the present invention measured at 190°C under a load of 2160 g is preferably 0.1 g/10 minutes to 50 g/10 minutes, more preferably 0.5 g/10 minutes to 20 g/10 minutes.

In addition, MFR is the value measured by the method according to JIS K7210-1999 at 190 degreeC and a load of 2160g.

The degree of neutralization of the resin composition is not particularly limited, but it is preferably 10% to 85%, and more preferably 15% to 82%. If the degree of neutralization of the resin composition is 10% or more, the wafer splittability can be further improved, and if it is 85% or less, the moldability of the film is excellent. The degree of neutralization of the resin composition basically depends on the degree of neutralization of the ionic polymer (A) and its content, and can be calculated by the following formula.

(Neutralization degree of resin composition) = (neutralization degree of ionic polymer (A)) × (ratio of ionic polymer (A) in resin composition)

Therefore, when the degree of neutralization of the ionic polymer (A) is low, its content is slightly higher, or when the degree of neutralization of the ionic polymer (A) is high, its content is slightly smaller, This can adjust the degree of neutralization of the resin composition.

Furthermore, when the resin composition of the present invention is processed into a film having a thickness of 100 μm, the heat shrinkage rate at 80° C. is preferably 6% or more, and more preferably 7% or more. If the heat shrinkage rate at 80° C. is 6% or more, it can be preferably used to produce a dicing film capable of eliminating slack through the heat shrinking step. The upper limit of the heat shrinkage rate is not particularly limited, and it is preferably 20% or less from the viewpoint of a decrease in the defect rate in the subsequent step (pickup step) after heat shrinkage.

In addition, in this case, the heat shrinkage rate at 80 degreeC is the value measured by the following method.

The resin composition film was cut into a thickness of 100 μm, a width of 25 mm×a length of 150 mm, and a reticle with an interval of 100 mm was marked as a test piece sample. Place it on a glass plate sprinkled with starch and heat it on a hot plate at 80°C for 2 minutes. Measure the interval between the marks on the film after heating and calculate the shrinkage (%) according to the following formula.

Shrinkage (%)=100mm- the distance between the marked lines after shrinkage (mm)/100mm×100

1-5. Manufacturing method of resin composition

The resin composition for a dicing film base material can be obtained by mixing the resin (A) and the resin (B), and further other polymers or additives as needed. As described above, since the Fika softening point specified in JIS K7206-1999 of the resin composition of the present invention is less than 50°C, the resin (A) is selected in such a way that the Fika softening point of the resin composition is less than 50°C. , Resin (B) and the type or amount of additives required.

The production method of the resin composition is not particularly limited, and for example, it can be obtained by dry-blending all the components and melt-kneading.

2. Cutting film substrate

The second aspect of the present invention is a dicing film base material that contains at least one layer containing the resin composition for a dicing film base material. 1A and 1B are cross-sectional views showing an embodiment of the dicing film substrate 10 of the present invention. FIG. 1A is a single-layer dicing film substrate containing only the first resin layer 1 containing the above-mentioned resin composition for dicing film substrates, and FIG. 1B is a first resin layer 1 containing the resin composition for dicing film substrates above. The multilayer dicing film base material laminated with the second resin layer 2 containing other resin or resin composition.

The strength of the dicing film substrate of the present invention is preferably within a range of 25% modulus of 5 MPa or more and 15 MPa or less, and more preferably 6 MPa or more and 12 MPa or less. If the 25% modulus is 5 MPa or more, the wafer splitting property (strength) as the dicing film base is excellent, and if it is 15 MPa or less, the expandability is excellent.

The modulus in the present invention is based on JIS K 7127-1999. For the mechanical axis direction (MD direction, Machine Direction) and orthogonal direction (TD direction, Transverse Direction) of the cutting film substrate, the test speed is 500 mm/min, Test piece: width 10 mm × length 200 mm, fixture interval: 100 mm, measured as the film strength (25% modulus or 50% modulus) at an elongation distance of 25% or 50%.

The heat shrinkage rate of the dicing film substrate of the present invention at 80°C is preferably in the range of 6% or more and 20% or less, and more preferably 7% or more. If the heat shrinkage rate at 80°C is 6% or more, the heat shrinkage characteristics (elimination of slack) of the dicing film substrate is excellent, and if it is 20% or less, the following steps (pickup step) after heat shrinkage The defect rate is excellent.

In addition, in this case, the heat shrinkage rate at 80 degreeC is the value measured by the following method.

The dicing film base material was cut into a thickness of 100 μm, a width direction of 25 mm × a length direction 150mm, marking lines with intervals of 100mm are marked as test piece samples. Place it on a glass plate sprinkled with starch and heat it on a hot plate at 80°C for 2 minutes. Measure the interval between the marks on the film after heating and calculate the shrinkage (%) according to the following formula.

Shrinkage (%)=100mm- the distance between the marked lines after shrinkage (mm)/100mm×100

2-1. The first resin layer

The first resin layer contains the above-mentioned resin composition for a dicing film base material, that is, an ionic polymer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of 30 parts by mass or more and 90 parts by mass or less and Ethylene-based copolymer (B) 10 parts by mass or more and 70 parts by mass or less (where the total of component (A) and component (B) is 100 parts by mass), and the Fika softening point specified in JIS K7206-1999 The layer of the resin composition for dicing film substrates below 50°C. In addition, the first resin layer may be a layer composed of the resin composition for a dicing film base. Such a resin composition layer has an excellent balance between the strength and the heat shrinkage rate.

When the dicing film base material has a single-layer structure, it is preferable that the content of the ionic polymer (A) in the resin composition as the raw material is 70 parts by mass or more and 90 parts by mass or less, and the ethylene-based copolymer (B) The content is 10 parts by mass or more and 30 parts by mass or less, more preferably the content of the ionic polymer (A) is 80 parts by mass or more and 90 parts by mass or less, and the content of the ethylene-based copolymer (B) is 10 parts by mass or more and 20 parts by mass or less (wherein the total of component (A) and component (B) is set to 100 parts by mass). In this way, by using a resin composition having a high ratio of ionic polymer (A), even if it is a single layer, the strength required as a dicing film substrate can be achieved.

On the other hand, when the dicing film base material has a multi-layer structure, the resin composition that becomes the raw material of the first resin layer may be the resin composition of the present invention, The ratio of the ionic polymer (A) to the copolymer (B) is not particularly limited, as long as the content of the ionic polymer (A) is 30 parts by mass or more and 90 parts by mass or less, and the content of the ethylene-based copolymer (B) is 10 It is sufficient if it is more than 70 parts by mass.

2-2. Second resin layer

The second resin layer is a layer containing a resin (C) or a layer composed of a resin (C), and the resin (C) is not particularly limited as long as it has a high adhesiveness with the resin composition constituting the first resin layer . By laminating the second resin layer containing the resin (C) (or consisting of the resin (C)) and the first resin layer, the strength of the dicing film base material can be improved without causing the problem of delamination between layers, and Maintain the balance between the dividability and dilatability of wafers required for dicing films.

<Resin C>

The resin (C) in the present invention is preferably an ionic polymer from an ethylene-unsaturated carboxylic acid copolymer (hereinafter, also simply referred to as "copolymer (C)") and the above ethylene-unsaturated carboxylic acid copolymer (Hereinafter, also simply referred to as "ionic polymer (C)") At least one selected from the group consisting of. The ionic polymer of the ethylene-unsaturated carboxylic acid copolymer used as the resin (C) is obtained by neutralizing a part (or all) of the carboxyl groups of the above ethylene-unsaturated carboxylic acid copolymer.

In addition, as described below in detail, the resin (C) may be the same resin as the resin (A) or the resin (B) contained in the resin composition constituting the first resin layer.

The above-mentioned copolymer (C), or the ethylene-unsaturated carboxylic acid-based copolymerization system constituting the ionic polymer (C) is a copolymer of at least a binary copolymer formed by copolymerizing ethylene and an unsaturated carboxylic acid. The third copolymerization component is formed by copolymerization of ternary or more Of multiple copolymers. Furthermore, one kind of ethylene-unsaturated carboxylic acid-based copolymer may be used alone, or two or more kinds of ethylene-unsaturated carboxylic acid-based copolymers may be used in combination.

Examples of the unsaturated carboxylic acid constituting the ethylene-unsaturated carboxylic acid binary copolymer include acrylic acid, methacrylic acid, ethyl acrylic acid, itaconic acid, itaconic anhydride, fumaric acid, butenoic acid, Maleic acid, maleic anhydride and other unsaturated carboxylic acids with 4-8 carbon atoms. Particularly preferred is acrylic acid or methacrylic acid.

When the ethylene-unsaturated carboxylic acid-based copolymer (C) is a ternary or more multi-component copolymer, a monomer (third copolymerization component) that forms a multi-component copolymer may be included. Examples of the third copolymerization component include unsaturated carboxylic acid esters (for example, methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, and methacrylic acid) Ethyl ester, isobutyl methacrylate, dimethyl maleate, diethyl maleate and other (meth)acrylic acid alkyl esters), unsaturated hydrocarbons (for example, propylene, butene, 1 , 3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), vinyl esters (for example, vinyl acetate, vinyl propionate, etc.), vinyl sulfuric acid or vinyl nitric acid, etc. Oxides, halogen compounds (for example, vinyl chloride, vinyl fluoride, etc.), vinyl-containing primary/secondary amine compounds, carbon monoxide, sulfur dioxide, etc., as these copolymerization components, unsaturated carboxylic acid esters are preferred.

For example, in the case where the ethylene-unsaturated carboxylic acid-based copolymer (C) is a ternary copolymer, it can be preferably exemplified by the ternary copolymer of ethylene and unsaturated carboxylic acid and unsaturated carboxylic acid ester, ethylene and Ternary copolymer of unsaturated carboxylic acid and unsaturated hydrocarbon, etc.

The unsaturated carboxylic acid ester is preferably an unsaturated carboxylic acid alkyl ester, and the carbon number of the alkyl portion of the alkyl ester is preferably 1-12, more preferably 1-8, and still more preferably 1-4. Examples of alkyl sites include methyl, ethyl, n-propyl, isopropyl, N-butyl, isobutyl, second butyl, 2-ethylhexyl, isooctyl, etc.

Specific examples of unsaturated carboxylic acid esters include: unsaturated carboxylic acid alkyl esters having 1 to 12 carbon atoms in the alkyl portion (eg, methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate) Alkyl acrylates such as esters, isooctyl acrylate, alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, dimethyl maleate, maleate Diethyl diacid and other maleic acid alkyl esters) and so on.

Among the unsaturated carboxylic acid alkyl esters, the (meth)acrylic acid alkyl esters having 1 to 4 carbon atoms in the alkyl portion are more preferable.

The form of the copolymer may be any of a block copolymer, a random copolymer, and a graft copolymer, and may also be any of a binary copolymer or a multi-component copolymer of three or more. Among them, in terms of industrial availability, it is preferably a binary random copolymer, a ternary random copolymer, a graft copolymer of a binary random copolymer, or a graft copolymer of a ternary random copolymer The combination is more preferably a binary random copolymer or a ternary random copolymer.

Specific examples of the ethylene-unsaturated carboxylic acid-based copolymer include three-component copolymers such as ethylene-acrylic acid copolymers and ethylene-methacrylic acid copolymers, and ethylene-methacrylic acid-isobutyl acrylate copolymers. Yuan copolymer. In addition, a commercially available product listed as an ethylene-unsaturated carboxylic acid-based copolymer can also be used, and for example, Nucrel Series (registered trademark) manufactured by Dow-Mitsui Polychemicals Co., Ltd. can be used.

The copolymerization ratio (mass ratio) of the unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid-based copolymer is preferably 4% by mass to 20% by mass, and more preferably 5% by mass to 15% by mass. Copolymerization ratio of unsaturated carboxylic acid ester in ethylene-unsaturated carboxylic acid copolymer (Mass ratio) is preferably 1% by mass to 20% by mass, and more preferably 5% by mass to 18% by mass. From the viewpoint of expandability, the content ratio of the structural unit derived from the unsaturated carboxylic acid ester is preferably 1% by mass or more, and preferably 5% by mass or more. In addition, from the viewpoint of preventing blocking and fusion, the content ratio of the structural unit derived from the unsaturated carboxylic acid ester is preferably 20% by mass or less, and more preferably 18% by mass or less.

In the present invention, the ionic polymer (C) used as the resin (C) is preferably obtained by crosslinking (neutralizing) the carboxyl group contained in the above ethylene-unsaturated carboxylic acid-based copolymer via metal ions at an arbitrary ratio By. Examples of the metal ion used in the neutralization of the acid group include metal ions such as lithium ion, sodium ion, potassium ion, rubidium ion, cesium ion, zinc ion, magnesium ion, and manganese ion. Among these metal ions, in terms of the availability of industrial products, magnesium ions, sodium ions and zinc ions are preferred, sodium ions and zinc ions are more preferred, and zinc ions are particularly preferred.

One metal ion may be used alone, or two or more may be used in combination.

The degree of neutralization of the ethylene-unsaturated carboxylic acid copolymer in the ionic polymer (C) is preferably 10% to 85%, and more preferably 15% to 82%. If the degree of neutralization is 10% or more, the wafer splittability can be further improved, and if it is 85% or less, the film has excellent processability or moldability.

In addition, the degree of neutralization is the ratio (mol %) of the number of carboxyl groups neutralized with metal ions to the total number of carboxyl groups contained in the ethylene-unsaturated carboxylic acid copolymer.

The melt flow rate (MFR) of the resin (C) is preferably in the range of 0.2 g/10 minutes to 20.0 g/10 minutes, more preferably 0.5 g/10 minutes to 20.0 g/10 minutes, and still more preferably 0.5 g/ 10 minutes~18.0g/10 minutes. If the melt flow rate is within the above range, it is advantageous when the film is formed.

Furthermore, MFR is loaded at 190°C by a method according to JIS K7210-1999 The value measured at 2160g.

The resin (C) preferably has a Fica softening point of 50°C or higher and 100°C or lower. By laminating a resin with a higher Fica softening point as the second resin layer in the first resin layer containing a resin composition with a Fika softening point of less than 50°C, the strength or heat resistance of the dicing film substrate can be improved.

In addition, the Fika softening point is a value measured according to the A50 method specified in JIS K7206-1999.

<Other polymers and additives>

Various resins or other resins may be added as necessary to the resin (C) constituting the second resin layer as long as the effect of the present invention is not impaired. Examples of the above-mentioned additives include antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, pigments, dyes, slip agents, anti-blocking agents, antistatic agents, mildew inhibitors, antibacterial agents, and flame retardants. , Flame retardant additives, crosslinking agents, crosslinking additives, foaming agents, foaming additives, inorganic fillers, fiber reinforced materials, etc. From the viewpoint of preventing thermal fusion, the aforementioned additives may be added in small amounts.

2-3. Layer composition

The dicing film base material of the present invention includes a single-layer structure including the first resin layer 1 (FIG. 1A) and a multi-layer structure including the first resin layer 1 and the second resin layer 2 (FIG. 1B ). As long as the dicing film base material having a multi-layer structure includes the above two layers, the layer structure is not particularly limited. From the viewpoint of preventing delamination between layers, it is preferable that the first resin layer and the second resin layer are directly laminated.

The dicing film base material of a multilayer structure may be a multilayer structure of 3 layers or more. For example, the resin composition that constitutes the first resin layer can be used in several layers The second resin layer may be provided after the formed sheet is formed, and the second resin layer may be sandwiched between two first resin layers. In addition, it may have a configuration in which not only the first resin layer and the second resin layer but also other resin layers are laminated.

Representative examples of the resin constituting the other resin layer laminated with the dicing film base material of the present invention include: selected from linear low density polyethylene (LLDPE), low density polyethylene (LDPE), and ethylene-α-olefin The monomer in the interpolymer, polypropylene, and ethylene-vinyl ester copolymer may contain any number of blends.

In addition, the other resin layer to be laminated may be a functional layer (for example, an adhesive sheet, etc.), or may be a base material such as a polyolefin film (or sheet), a polyvinyl chloride film (or sheet), or the like. The above-mentioned substrate can be any structure having a single layer or multiple layers. In the present invention, these substrates are referred to as "cutting film substrates".

The surface of the dicing film substrate may also be subjected to known surface treatments such as corona discharge treatment to improve the adhesion of the dicing film substrate surface.

In addition, from the viewpoint of improving heat resistance, the first resin layer, the second resin layer or other resin layers, or the dicing film base material may be subjected to electron beam irradiation as necessary.

2-4. Manufacturing method of cutting film substrate

As a method of manufacturing a single-layer dicing film base material, a method of processing the resin composition for dicing film into a film shape by a known method can be mentioned. The method of processing the resin composition into a film shape is not particularly limited, and for example, the conventionally known T-shaped die casting molding method, T-shaped roll molding method, inflation molding method, extrusion lamination method, calender molding method, etc. Various forming methods produce films.

As a method of manufacturing the multilayer dicing film base material, the resin composition constituting the first resin layer and the resin (C) constituting the second resin layer are each known by The method is processed into a film, and the method of lamination. The method of processing the resin composition or the resin into a film is not particularly limited, and for example, it may be a conventionally known T-shaped die casting method, T-shaped roll forming method, inflation forming method, extrusion lamination method, and calendering Various forming methods such as methods are used to produce films.

Moreover, the multilayer dicing film base material can be manufactured by, for example, co-extrusion lamination of the resin composition constituting the first resin layer and the resin (C) constituting the second resin layer.

For example, when the resin composition constituting the first resin layer is laminated on the surface of the resin (C) film that becomes the second resin layer with a T-shaped film forming machine or an extrusion coating forming machine, in order to improve The adhesiveness with the second resin layer can be formed through the adhesive resin layer by a co-extrusion coating molding machine. Regarding such an adhesive resin, as a representative example, a monomer selected from the above-mentioned various ethylene copolymers, or unsaturated carboxylic acid grafts thereof, or a blend containing any number of them may be mentioned.

In addition, as a forming example of the dicing film base material of the present invention, a method of using a T-shaped film forming machine or an extrusion coating forming machine to heat bond the resin composition constituting the first resin layer to A multilayer body is formed on the surface of the resin (C) film that becomes the second resin layer.

In addition, although the method of forming a layer containing the resin composition as the first resin layer on the film of the resin (C) as the second resin layer is described, in contrast to this, 1 The film of the resin composition of the resin layer is formed of a resin (C) which becomes the second resin layer, or a method of providing the first resin or the second resin layer on another resin layer to produce the dicing film base of the present invention material.

The thickness of the dicing film base material is not particularly limited, and if it is considered as a constituent member of the dicing film, it is preferably 65 μm or more from the viewpoint of holding the frame during dicing. From the viewpoint of expandability, it is preferably 200 μm or less. In addition, the thickness of each resin layer constituting the multi-layer dicing film base material is not particularly limited as long as the total of these does not exceed the above-mentioned thickness of the dicing film base material, and it is preferable that both the first resin layer and the second resin layer are 30 μm or more Moreover, the thickness of the first resin layer and the second resin layer is preferably 30/70 to 70/30 when the thickness is 100 μm or less.

3. Cutting film

The third aspect of the present invention is a dicing film provided with the above-mentioned dicing film base material of the present invention and an adhesive layer laminated on at least one side thereof. 2A and 2B are cross-sectional views showing an embodiment of the dicing film 20 of the present invention. The dicing film 20 shown in FIG. 2A has a dicing film base material 10 including only the first resin layer 1 and an adhesive layer 11 provided on the surface thereof. The dicing film 20 shown in FIG. 2B has a first resin layer 1 and 2 The dicing film substrate 10 of the resin layer 2 and the adhesive layer 11 provided on the surface thereof.

The dicing film is preferably formed by forming an adhesive layer on the outermost layer. The adhesive layer is disposed on the surface of the cutting film substrate. The dicing film can be attached to the semiconductor wafer through the adhesive layer to cut the semiconductor wafer. In addition, in FIG. 2B, the adhesion layer 11 is arrange|positioned on the 1st resin layer 1 containing the resin composition for dicing film base materials of this invention, but this invention is not limited to this structure. The adhesive layer 11 may also be disposed on the second resin layer 2 (or other resin layer).

<adhesive layer>

The dicing film of the present invention is provided with the dicing film base material of the present invention and the adhesive layer provided on one side of the dicing film base material, and the semiconductor wafer that becomes the object of dicing processing is bonded and fixed on the adhesive layer. The thickness of the adhesive layer also depends on the type of adhesive, preferably 3~100 μm, more preferably 3 to 50 μm.

As the adhesive constituting the adhesive layer, conventionally known adhesives can be used. Examples of adhesives include: rubber-based, acrylic-based, polysiloxane-based, and polyvinyl ether-based adhesives; radiation-curing adhesives; and heating-foaming adhesives. Among them, if the peelability of the dicing film from the semiconductor wafer is considered, the adhesive layer preferably contains an ultraviolet curing adhesive.

Examples of the acrylic adhesive that can constitute the adhesive layer include: a homopolymer of (meth)acrylate and a copolymer of (meth)acrylate and a copolymerizable monomer. Specific examples of (meth)acrylates include: (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth ) Alkyl (meth)acrylate such as octyl acrylate, isononyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxyhexyl (meth)acrylate, etc. Hydroxyalkyl (meth)acrylate, glycidyl (meth)acrylate, etc.

Specific examples of copolymerizable monomers with (meth)acrylate include: (meth)acrylic acid, itaconic acid, maleic anhydride, (meth)acrylamide, (meth)acrylic acid N-hydroxyl Methylamide, alkylaminoalkyl (meth)acrylate (for example, dimethylaminoethyl methacrylate, tert-butylaminoethyl methacrylate, etc.), vinyl acetate, benzene Ethylene, acrylonitrile, etc.

The ultraviolet curing adhesive that can constitute the adhesive layer is not particularly limited, and contains the above acrylic adhesive, ultraviolet curing component (component capable of adding carbon-carbon double bond to the polymer side chain of the acrylic adhesive), and photopolymerization Starter. Furthermore, additives such as a crosslinking agent, an adhesion-imparting agent, a filler, an anti-aging agent, a coloring agent, and the like may be added to the ultraviolet curing adhesive as necessary.

Examples of ultraviolet curing components contained in ultraviolet curing adhesives Such as a monomer, oligomer or polymer that has a carbon-carbon double bond in the molecule and can be hardened by free radical polymerization. Specific examples of ultraviolet curing components include: trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol ( Methacrylates, neopentyl glycol di(meth)acrylates, dipentaerythritol hexa(meth)acrylates, etc. esters of (meth)acrylic acid and polyols or their oligomers; 2-propenyl cyanurate Di-3-butenyl ester, isocyanuric acid 2-hydroxyethyl bis(2-propenyloxyethyl) ester, isocyanuric acid tris (2-propenyloxyethyl) ester, isocyanuric acid tri (2-Methacryloyloxyethyl) ester and other isocyanurate and the like.

、十二烷基9-氧硫

、二甲基9-氧硫

、二乙基9-氧硫

等9-氧硫

類等。 Specific examples of the photopolymerization initiator contained in the ultraviolet-curable adhesive include: benzoin alkyl ethers such as benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and aromatics such as α-hydroxycyclohexyl phenyl ketone Ketones, aromatic ketals such as benzoyl dimethyl ketal, polyvinyl benzophenone, chlorine 9-oxysulfide

、Dodecyl 9-oxysulfur

Dimethyl 9-oxysulfur

, Diethyl 9-oxysulfur

9-oxygen sulfur

Class etc.

Examples of the crosslinking agent contained in the ultraviolet curing adhesive include: polyisocyanate compounds, melamine resins, urea resins, polyamines, carboxyl group-containing polymers, and the like.

It is preferable to attach a separator to the surface of the adhesive layer of the dicing film of the present invention. By attaching a separator, the surface of the adhesive layer can be kept smooth. In addition, the operation or transportation of the film for semiconductor manufacturing is facilitated, and marking processing can also be performed on the separator.

The separator may be paper, or synthetic resin film of polyethylene, polypropylene, polyethylene terephthalate, etc. In addition, the surface of the isolation film that is in contact with the adhesive layer may be subjected to mold release treatment such as polysiloxane treatment or fluorine treatment as necessary to improve the peelability of the self-adhesive layer. The thickness of the separator is usually about 10 to 200 μm, preferably about 25 to 100 μm.

<Manufacturing method of cutting film>

When manufacturing the dicing film of the present invention, the following method can be used, that is, a known method such as a gravure roll coater, reverse roll coater, touch roll coater, dip roll coater, bar coater can be used , Blade coater, spray coater and other methods to directly apply the adhesive to the cutting film substrate, or apply the adhesive to the release sheet by the above-mentioned known method and set the adhesive layer, then stick to The method of cutting the surface layer of the film substrate and transferring the adhesive layer.

Further, by co-extrusion of the resin composition of the present invention and the material constituting the adhesive layer (co-extrusion molding method), a dicing film as a laminate of the dicing film base material and the adhesive layer of the present invention can be obtained. Furthermore, by providing a second resin layer on the base material (first resin layer) side of the obtained laminate, a dicing film having a dicing film base material including the first resin layer and the second resin layer can also be produced.

In addition, the layer of the adhesive composition may be heated and cross-linked as necessary to make it an adhesive layer.

Furthermore, a separator may be attached to the surface of the adhesive layer.

[Example]

Next, the present invention will be described in detail based on examples, but the present invention is not limited to these examples.

1. Resin (A)

As the resin (A), a zinc (Zn) ion-neutralizing ion polymer of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer or ethylene-unsaturated carboxylic acid copolymer described in Table 1 below ( Hereinafter, referred to as "ionic polymer").

[Table 1]

2. Resin (B)

As the resin (B), an ethylene-based copolymer shown in Table 2 below was prepared.

The Fika softening temperatures in Tables 1 and 2 are measured according to the A50 method specified in JIS K7206-1999.

The MFR (melt flow rate) in Table 2 is the value measured according to JIS K7210-1999 at 190°C under a load of 2160 g.

The melting point in Table 2 is the value measured by the DSC method.

3. Resin (C)

As the resin (C), an ionic polymer 1 (IO-1) (same as the user used as the resin (A)) is prepared (refer to Table 1 above).

(Example 1)

The resin (A) and the resin (B) in the ratio (mass %) shown in Table 3 were dry blended. Then, the dry blended mixture was put into a resin inlet of a 40 mmΦ uniaxial extruder, and melt-kneading was performed at a die temperature of 200°C, thereby obtaining a resin composition for the first resin layer.

The obtained resin composition for the first resin layer and the resin (C) for the second resin layer were put into the respective extruders using two types of two-layer 40mmΦ T-shaped film forming machines, and the processing temperature was 240°C. Under the molding, two types of 2-layer T-shaped film with a thickness of 100 μm were produced. The thickness ratio of the first layer and the second layer in the 100 μm thick laminated film having a double-layer structure was set to 60/40.

(Examples 2-8 and 12-14, Comparative Examples 1-3, 5 and 10)

The resin composition for the first resin layer was prepared in the same manner as in Example 1 except that the types and amounts of resin (A) and resin (B) were changed as shown in Table 3 or Table 4. Next, the thicknesses of the first resin layer and the second resin layer were changed as shown in Table 3 or Table 4, except that the build-up layer including the first resin layer and the second resin layer was produced in the same manner as in Example 1. membrane.

(Examples 9-11, Comparative Examples 4 and 6-9)

The resin composition for the first resin layer was prepared in the same manner as in Example 1 except that the types and amounts of resin (A) and resin (B) were changed as shown in Table 3 or Table 4. Then, without using the resin (C), using the produced resin composition, In the same manner as in Example 1, a 100 μm thick T-shaped film was produced.

The resin composition and film for the first resin layer obtained in the above examples and comparative examples were evaluated by the following methods. The evaluation results are shown in Table 3 or Table 4.

(1) Neutralization degree of resin composition

The degree of neutralization is calculated based on the degree of neutralization of the resin (A) and its content.

(2) MFR of resin composition

MFR is measured according to JIS K7210-1999 at 190°C under a load of 2160g.

(3) Fica softening temperature of resin composition

The Fika softening temperature is measured according to the A50 method specified in JIS K7206-1999.

(4) 80℃ shrinkage

The resin composition was molded on a film with a thickness of 100 μm, cut into a width of 25 mm × a length of 150 mm, and a reticle with an interval of 100 mm was marked as a test piece sample. Sprinkle starch (Nikkari powder, manufactured by Nikka Co., Ltd.) on the glass plate to prevent the film from adhering, place the test piece sample on it, and heat at 80°C for 2 minutes on the hot plate of the press forming machine. Measure the interval between the marks on the film after heating and calculate the shrinkage (%) according to the following formula.

Shrinkage (%)=100mm- the distance between the marked lines after shrinkage (mm)/100 mm×100

(5) Tensile test (modulus)

The dicing film base material was cut into short strips of 10 mm in width and used as the measurement object. According to JIS K7127, under the conditions of test piece: width 10mm × length 200mm, clamp interval: 100mm, the film strength (25%) when the elongation distance in the MD and TD directions of the measurement object is 25% and 50% respectively Modulus and 50% modulus). In addition, the test speed was set to 500 mm/min.

[table 3]

[Table 4]

Regarding the use of an ionic polymer containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer (ternary copolymer), that is, a resin (A) of 30 parts by mass or more and 90 parts by mass or less, and an ethylene-based copolymer (B) ) The dicing film substrate of the embodiment produced by the resin composition of 10 parts by mass or more and 70 parts by mass or less and the Fica softening point of less than 50°C has excellent heat (80°C) shrinkage and strength. On the other hand, the resin composition of Comparative Example 1 obtained by using the ionic polymer of the binary copolymer has a Fica softening point exceeding 50°C. The thermal shrinkage rate of the dicing film base material produced by using such a resin composition is low. Although the resin film compositions of Comparative Examples 2 and 3, which contain the resin (A) and the resin (B) but whose Fica softening point exceeds 50°C, were also the same as Comparative Example 1, the heat shrinkage ratio was low.

Examples obtained by using a resin composition containing 70 parts by mass or more and 90 parts by mass or less of resin (A) and 30 parts by mass or more and 10 parts by mass or less of resin (B), and having a Fica softening point of less than 50°C Although the cutting film substrate of 9~11 is a single layer, it also exerts sufficient strength and heat shrinkability.

The resin compositions of Comparative Examples 4 and 5 containing more than 90 parts by mass of the resin (A) and less than 10 parts by mass of the resin (B) have a Fica softening point exceeding 50°C. Although the substrate of the dicing film produced by using such a resin composition has high strength, its thermal shrinkage rate is low. Similarly, the dicing film substrates of Comparative Examples 6 to 10 using an ionic polymer as the first resin layer also showed higher strength, but the thermal shrinkage rate was lower. In particular, although the ionic polymer 2 used in Comparative Example 7 had a Fica softening point of less than 50°C, the thermal shrinkage rate was low.

From these results, it is known that in order to obtain a dicing film substrate having both high strength and high thermal shrinkage, it is important that the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer in the resin composition that becomes the raw material The content of ionic polymer or resin (A) It is 30 mass parts or more and 90 mass parts or less, and the content of the resin (B) which is an ethylene-based copolymer is 10 mass parts or more and 70 mass parts or less, and the Fica softening point is less than 50°C.

This application claims priority based on Japanese Patent Application No. 2018-149562 filed on August 8, 2018. The contents of the application specification are all cited in the specification of the case.

(Industry availability)

The dicing film of the present invention can be preferably used for a method of manufacturing a semiconductor device that not only implements a dicing step and an expansion step for dividing a semiconductor wafer into wafer units, but also performs a heat shrinking step. In particular, since the cutting film of the present invention has both high strength and high heat shrinkage, it can be preferably used for applying the conventional method (blade cutting method or laser ablation method, etc.) to the cutting film in the expansion step Manufacturing method of invisible cutting (registered trademark) method of large stress. By using the dicing film of the present invention, the interval of the divided wafers can be made uniform, and the product defects in the subsequent steps can be reduced, so that the semiconductor device can be manufactured with higher yield.

1‧‧‧The first resin layer

2‧‧‧The second resin layer

10‧‧‧Cut film base material

Claims (10)

A resin composition for a dicing film base material, comprising: an ionic polymer (A) of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of 30 parts by mass or more and 90 parts by mass or less, and 10 parts by mass or more and 70 parts by mass or less of the ethylene-based copolymer (B) (where the total of the component (A) and the component (B) is set to 100 parts by mass), and The Fika softening point specified in JIS K7206-1999 is less than 50°C. The resin composition for a dicing film base material according to claim 1, wherein the above-mentioned ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer ionic polymer (A) has the Fika softening point specified in JIS K7206-1999 It is 25°C or more and 60°C or less. The resin composition for a dicing film base material according to claim 1, wherein the ethylene-based interpolymer (B) is a resin having a Fika softening point defined by JIS K7206-1999 of 50°C or lower, or does not have the above-mentioned Fika softening Point of resin. The resin composition for a dicing film substrate according to claim 1, wherein the ethylene-based copolymer (B) is selected from the group consisting of an ethylene-α-olefin copolymer and an ethylene-unsaturated carboxylate copolymer At least one. The resin composition for a dicing film base material according to claim 1, wherein the melt flow rate (MFR) of the above-mentioned ethylene-based interpolymer (B) measured by a method according to JIS K7210-1999 at 190°C under a load of 2160 g It is 0.2g/10min~30.0g/10min. The resin composition for a dicing film base material according to claim 1, wherein the melt flow rate (MFR) of the resin composition for a dicing film base material measured by a method according to JIS K7210-1999 at 190°C under a load of 2160 g (MFR ) Is 0.1g/10min~50g/10min. A dicing film base material comprising at least one layer containing the resin composition for a dicing film base material of claim 1. The dicing film substrate according to claim 7, which includes: a first resin layer containing the resin composition for a dicing film substrate according to claim 1, and The second resin layer including the resin (C) laminated on the first resin layer. The dicing film substrate according to claim 8, wherein the resin (C) is selected from the group consisting of an ethylene-unsaturated carboxylic acid copolymer and an ionic polymer of the ethylene-unsaturated carboxylic acid copolymer At least 1 kind. A cutting film, characterized by having: the cutting film substrate of any one of claims 7 to 9, and An adhesive layer deposited on at least one side of the dicing film substrate.

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