KR20210029792A - Resin composition for dicing film substrate, dicing film substrate, and dicing film - Google Patents

Abstract

It provides a resin composition for a dicing film base material for producing a dicing film in which high strength and high heat shrinkage are compatible. Ionomer (A) of ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer (A) 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 (however, component (A)) And a total of 100 parts by mass of the component (B)), and having a Vicat softening point specified in JIS K7206-1999 of less than 50° C., a resin composition for a dicing film base material, and a dicing film using the resin composition Substrate and dicing film.

Description

Resin composition for dicing film substrate, dicing film substrate, and dicing film

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

In the manufacturing process of a semiconductor device such as an IC, after thinning a semiconductor wafer having a circuit pattern formed thereon, it is common to perform a dicing process for dividing the semiconductor wafer into chips. In the dicing process, after affixing a wafer processing film (referred to as a dicing film or dicing tape) having elasticity on the back surface of the semiconductor wafer, the semiconductor wafer is chipped by a dicing blade or laser light. It is divided into. Then, in the next expansion step (also referred to as an expand step), the dicing tape corresponding to the cut wafer is expanded to form chips into small pieces.

In the expand process, the dicing film is expanded (expanded) by pushing up the expansion table provided under the dicing film, for example. At this time, in order to divide the chips, it is important that the dicing film is uniformly expanded over the entire surface of the expansion table. Moreover, since the stress applied to the dicing film at the periphery of the extension table is greater than that of the center of the extension table, the dicing film after the extension step causes sagging in the portion corresponding to the periphery of the extension table. Such sagging may make the spacing of the divided chips non-uniform, and furthermore, may cause product defects in a later process.

As a means of eliminating sagging of a dicing film, a heat shrink process is known in which hot air with a yarn temperature of about 80 to 100°C is blown on the sagging portion, and the film is contracted by heating it to restore it to its original state ( For example, see Patent Document 1). In order to perform this step, the dicing film needs to have high heat shrinkability at a temperature of about 80°C.

In addition, as a dicing method that has recently been focused on, there is a stealth dicing (registered trademark) method. In this method, in the next expansion step in which a crack is formed inside, not the surface of the wafer by laser light, and is carried out at a low temperature (about -15°C to 0°C), the stress of the dicing film is used to To divide. By doing in this way, loss of a semiconductor product in a dicing process can be suppressed, and a yield can be raised. As the dicing film used herein, it is required to achieve both the strength to withstand the stress required for dividing the wafer and the heat shrinkage for eliminating sagging that may occur during the dividing of the wafer by a heat shrink process.

As a substrate for dicing films used for dicing films, a dicing film substrate having an ionomer obtained by crosslinking a compound having a carboxyl group with a cation and an octene-containing copolymer (Patent Document 2), and a Vicat softening point specified by JIS K7206 A dicing film substrate (Patent Document 3) having a lowermost layer made of a thermoplastic resin of 80° C. or higher, and another layer made of a thermoplastic resin having a Vicat softening point of 50° C. or more and less than 80° C. specified in JIS K7206, and JIS K7206. A dicing film substrate (Patent Document 4) made of a thermoplastic resin having a Vicat softening point of 50°C or more and less than 90°C is known.

In addition, Patent Document 5 discloses a dicing film suitable for stealth dicing (registered trademark) and excellent in expandability, wherein the initial elastic modulus at -10°C is 200 MPa or more and 380 MPa or less, and Tanδ (loss elastic modulus/storage A dicing film having an elastic modulus) of 0.080 or more and 0.3 or less is disclosed.

Japanese Unexamined Patent Application Publication No. Hei 9-007976 Japanese Unexamined Patent Application Publication No. 2000-345129 Japanese Unexamined Patent Application Publication No. 2009-231700 Japanese Unexamined Patent Application Publication No. 2011-216508 Japanese Unexamined Patent Application Publication No. 2015-185591

In Patent Document 1, as a dicing film capable of removing sagging by a heat shrink process, for example, an ionomer having a melting point of 71°C (an ionomer of a ternary polymer obtained by polymerization of acrylic acid ester, methacrylic acid ester, etc.) ) And a dicing film having a layer made of a blend of an ethylene-vinyl acetate copolymer, and the like are described. However, there is no description of the basic performance required for the dicing film, such as the expandability and strength of the dicing film.

In Patent Document 2, as specific examples of the substrate for dicing films, a substrate for dicing films having an octene-containing copolymer and an ionomer such as an ethylene/methacrylic acid/acrylic acid ester terpolymer is described. However, there is no description regarding the heat shrinkability of the dicing film.

The dicing film substrate of Patent Document 3, which has a layer made of a thermoplastic resin having a Vicat softening point of 80°C or higher, or the dicing film substrate of Patent Document 4, which is composed of a thermoplastic resin having a Vicat softening point of 50°C or more and less than 90°C, According to the research of the inventors, the heat shrinkage at 80°C is low, and it is considered that it is difficult to restore the sagging to its original state by the heat shrink process.

In addition, Patent Document 5 describes a dicing film having a base material containing an ethylene/α-olefin copolymer or an ionomer of an ethylene/α-olefin copolymer. However, in a substrate for a dicing film comprising an ionomer of a ternary or more polypolymer, such as ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester, or a resin composition containing a ternary or more polypolymer and an ethylene-based copolymer. There is no description about it.

The present invention has been made in view of the problems of such prior art, and its object is to provide a resin composition for a dicing film substrate for producing a dicing film in which high strength and high heat shrinkability are compatible. have. Further, an object of the present invention is to provide a dicing film substrate and a dicing film using the resin composition for dicing film substrates of the present invention.

That is, according to this invention, the resin composition for a dicing film base material, a dicing film base material, and a dicing film shown below are provided.

[1] 30 parts by mass or more and 90 parts by mass or less of the ionomer (A) of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, and 10 parts by mass or more and 70 parts by mass or less (the component (A) and the total of the component (B) are 100 parts by mass), and having a Vicat softening point specified in JIS K7206-1999 of less than 50° C., a resin composition for a dicing film substrate.

[2] The dicing according to [1], wherein the ionomer (A) of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer has a Vicat softening point specified in JIS K7206-1999 of 25°C or more and 60°C or less. Resin composition for a film base.

[3] As described in [1] or [2], wherein the ethylene-based copolymer (B) is a resin having a Vicat softening point of 50°C or less specified in JIS K7206-1999, or a resin having no Vicat softening point. A resin composition for a dicing film substrate.

[4] According to any one of [1] to [3], wherein the 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. A resin composition for a dicing film substrate.

[5] The ethylene-based copolymer (B) has a melt flow rate (MFR) of 0.2 g/10 min to 30.0 g/10 min measured at 190° C. and a load of 2160 g by a method in accordance with JIS K7210-1999. The resin composition for a dicing film base material in any one of [1]-[4].

[6] The melt flow rate (MFR) of the resin composition for a dicing film base material measured at 190°C and a load of 2160 g by a method in accordance with JIS K7210-1999 is 0.1 g/10 min to 50 g/10 min, The resin composition for dicing film base materials in any one of [1]-[5].

[7] A dicing film substrate including at least one layer containing the resin composition for dicing film substrates according to any one of [1] to [6].

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

[9] The dicing film substrate according to [8], wherein the resin (C) is at least one selected from the group consisting of an ethylene-unsaturated carboxylic acid-based copolymer and an ionomer of the ethylene-unsaturated carboxylic acid-based copolymer. .

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

The present invention provides a resin composition for a dicing film base material for producing a dicing film in which high strength and high heat shrinkability are compatible, and a dicing film base material and a dicing film using the same.

1A is a cross-sectional view showing an embodiment of the dicing film base material 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, in addition to explaining in detail the resin composition for a dicing film base material of the present invention, a dicing film base material and a dicing film are also described in detail.

In addition, in this specification, the notation of "~" which shows a numerical range is a meaning including the value of the lower limit value and the upper limit value of a numerical range.

In addition, "(meth)acrylic acid" is a notation used including both "acrylic acid" and "methacrylic acid", and "(meth)acrylate" is both "acrylate" and "methacrylate" It is a notation used including.

In the process of manufacturing a semiconductor wafer, in order to remove the sagging of the dicing film after the expansion (expand) process by using heat shrinkage of the film (to restore it to its original state), the dicing film is at a temperature around 80°C. It is necessary to have high heat shrinkability. In the present invention, the ionomer (A) of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer (A) 30 parts by mass or more and 90 parts by mass or less, and the ethylene-based copolymer (B) 10 parts by mass or more and 70 parts by mass or less (however, , By preparing a dicing film base material using a resin composition containing (a total of component (A) and component (B) is 100 parts by mass), a dicing film having both high strength and high heat shrinkability can be produced. there was. The mechanism is not clear, but I think it is as follows.

It is known that an ethylene-based copolymer improves its heat shrinkability by blending it with a polyolefin-based resin. However, when a film is produced from a resin composition containing a polyolefin-based resin and an ethylene-based copolymer, the strength and expandability of the film are insufficient as a dicing film. On the other hand, in the present invention, by using an ionomer of an ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer and an ethylene-based copolymer to prepare a resin composition having a Vicat softening point of less than 50°C, ion crosslinking of the ionomer A dicing film with improved heat shrinkability could be obtained without significantly lowering the film strength and expandability (dividing property) derived from the structure.

The dicing film of the present invention can be suitably used in a method for manufacturing a semiconductor device in which a heat shrink process is performed in addition to a dicing process and an expansion process for dividing a semiconductor wafer into chips. In particular, since the dicing film of the present invention has both high strength and high heat shrinkability, a stealth die in which a greater stress is applied to the dicing film than in conventional methods (blade dicing method, laser ablation method, etc.) in the expansion process. It can be suitably used for a manufacturing method employing the Sing (registered trademark) method. By using the dicing film of the present invention, the interval between the chips after division is made uniform, product defects in subsequent steps are reduced, and the semiconductor device can be manufactured with a high yield.

Hereinafter, although an exemplary embodiment is given and description of this invention is performed, this invention is not limited to the following embodiment.

1. Resin composition for dicing film substrate

The first aspect of the present invention is a resin composition for a dicing film substrate. The resin composition for a dicing film base material is 30 parts by mass or more and 90 parts by mass or less of the ionomer (A) of an ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, and 10 parts by mass or more and 70 parts by mass of the ethylene-based copolymer (B). It contains not more than parts (however, the total of component (A) and component (B) is 100 parts by mass).

1-1. Resin (A)

The ionomer of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer used as the resin (A) (hereinafter referred to only as ``ionomer (A)'') is an ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer. Some or all of the carboxyl groups of are neutralized with a metal (ion). In the present invention, the one in which at least part of the acid groups of the copolymer is neutralized with a metal (ion) is referred to as a "ionomer", and the one in which the acid group of the copolymer is not neutralized with a metal (ion) is referred to as a "copolymer". .

The ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer constituting the ionomer (A) is at least a ternary copolymer in which ethylene, an unsaturated carboxylic acid, and an unsaturated carboxylic acid ester are copolymerized, and a fourth It may be a 4-membered or more multi-component copolymer in which the copolymerization component is copolymerized. Further, the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer may be used singly or in combination of two or more ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymers.

Examples of unsaturated carboxylic acids constituting the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, maleic acid, anhydride. And unsaturated carboxylic acids having 4 to 8 carbon atoms such as maleic acid. In particular, acrylic acid or methacrylic acid is preferred.

As the unsaturated carboxylic acid ester constituting the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, an unsaturated carboxylic acid alkyl ester is preferable. The number of carbon atoms in the alkyl moiety of the alkyl ester is preferably 1 to 12, more preferably 1 to 8, and still more preferably 1 to 4. Examples of the alkyl moiety include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, 2-ethylhexyl, isooctyl, and the like. Specific examples of the unsaturated carboxylic acid alkyl ester include methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, dimethyl maleate, maleic acid. Alkyl (meth)acrylates, such as diethyl, are mentioned.

When the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer is a quaternary or more multi-component copolymer, a monomer (fourth copolymerization component) forming the multi-component copolymer may be included. As the fourth copolymerization component, unsaturated hydrocarbons (e.g., propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, etc.) Etc.), oxides such as vinyl sulfuric acid and vinyl nitric acid, halogen compounds (for example, vinyl chloride, vinyl fluoride, etc.), vinyl group-containing primary and secondary amine compounds, carbon monoxide, sulfur dioxide, and the like.

The form of the copolymer may be any of a block copolymer, a random copolymer, and a graft copolymer, or may be any of a ternary copolymer and a quaternary multipolymer. Among them, from the viewpoint of industrial availability, a three-membered random copolymer or a graft copolymer of a three-membered random copolymer is preferable, and a three-membered random copolymer is more preferable.

As specific examples of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, ternary copolymers such as ethylene/methacrylic acid/acrylate butyl ester copolymer may be mentioned.

Constituent units derived from unsaturated carboxylic acids when the total amount of the structural units constituting the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer in the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer is 100% by mass. The content ratio of 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. Constituents derived from unsaturated carboxylic acid esters when the total amount of the constituent units constituting the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer in the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer is 100% by mass. The content ratio of the unit 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. It is preferable that the content ratio of the structural unit derived from an unsaturated carboxylic acid ester is 1 mass% or more, preferably 5 mass% or more from the viewpoint of the expandability of the film. In addition, from the viewpoint of preventing blocking and fusion, the content ratio of the constituent units derived from unsaturated carboxylic acid esters is preferably 20% by mass or less, more preferably 18% by mass or less, and particularly preferably 17% by mass or less.

The ionomer (A) used as the resin (A) in the present invention is preferably a carboxyl group contained in the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer is crosslinked (neutralized) at an arbitrary ratio by metal ions. Do. Metal ions used for neutralization of acid groups include metal ions such as lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions, zinc ions, magnesium ions, and manganese ions. Among these metal ions, magnesium ions, sodium ions and zinc ions are preferable, sodium ions and zinc ions are more preferable, and zinc ions are particularly preferable from the ease of availability of industrial products.

Metal ions may be used alone or in combination of two or more.

Although there is no particular limitation on the degree of neutralization of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer in the ionomer (A) (hereinafter also referred to as ``the degree of neutralization of the ionomer (A)''), 10% to 100% Is preferable, and 30% to 100% are more preferable. When the degree of neutralization is within the above range, the film strength and the dividing property are improved, which is preferable.

In addition, the degree of neutralization of the ionomer (A) is the ratio (mol%) of carboxyl groups neutralized by metal ions to the number of moles of all carboxyl groups contained in the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer.

As the ionomer (A) of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, a commercially available product on the market may be used. As a commercial item, a Mitsui DuPont Polychemical Co., Ltd. product, a high Milan (registered trademark) series, etc. are mentioned, for example.

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

In addition, MFR is a value measured at 190°C and a load of 2160 g by a method in accordance with JIS K7210-1999.

Further, the Vicat softening point of the ionomer (A) of ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester is preferably 25°C or more and 60°C or less, and more preferably 35°C or more and 60°C or less. When the Vicat softening point of the ionomer (A) is within the above range, it is easy to adjust the Vicat softening point of the resin composition to less than 50°C.

In addition, the Vicat 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 substrate of the present invention is 30 parts by mass or more and 90 parts by mass or less with respect to 100 parts by mass in total of the resin (A) and the resin (B) described later, 40 parts by mass or more and 90 parts by mass or less are preferable, and 50 parts by mass or more and 70 parts by mass or less are more preferable. When the content of the resin (A) is 30 parts by mass or more, sufficient strength is obtained as a dicing film, and when it is 90 parts by mass or less, the thermal contraction rate can be increased.

1-2. Resin (B)

The ethylene-based copolymer (B) used as the resin (B) (hereinafter, also simply referred to as "copolymer (B)") is a copolymer of ethylene and other monomers, and there is no particular limitation on its kind. However, when preparing a resin composition with the ionomer (A) described above, it is important to combine the ionomer (A) and the copolymer (B) so that the Vicat softening point of the composition is less than 50°C. From this point of view, the copolymer (B) is preferably a resin having a Vicat softening point of 50°C or less, or a resin having no Vicat softening point. In addition, when the copolymer (B) has a Vicat softening point, it is preferable that the Vicat softening point is 25°C or higher from the viewpoint of workability.

In addition, the Vicat 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 an ethylene/α-olefin copolymer, an ethylene/unsaturated carboxylic acid ester copolymer, and an ethylene/vinyl ester copolymer, but ethylene/α-olefin Copolymers and ethylene/unsaturated carboxylic acid ester copolymers are preferred.

The ethylene/α-olefin copolymer is a copolymer of ethylene and an α-olefin. Only one type of α-olefin may be contained in the copolymer, or two or more types of α-olefins may be contained. In specific examples of the α-olefin, 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, and the like. Among them, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferable from the ease of availability. In addition, the ethylene/α-olefin copolymer may be a random copolymer or a block copolymer, and a random copolymer is preferable.

Although there is no particular limitation on the content ratio of the structural unit derived from ethylene contained in the ethylene/α-olefin copolymer, it is preferably more than 50 mol% and not more than 95 mol%, more preferably 70 mol% or more and 94 mol% or less. desirable. It is preferable that the proportion of the structural units derived from α-olefins contained in the ethylene/α-olefin copolymer (hereinafter, also referred to as “α-olefin units”) is 5 mol% or more and less than 50 mol%, and 6 mol% or more. It is more preferable that it is 30 mol% or less. Such an ethylene/α-olefin copolymer is advantageous in securing shrinkability.

As the ethylene/α-olefin copolymer, the density is preferably 895 kg/m 3 or less, particularly preferably 860 to 890 kg/m 3.

The ethylene/unsaturated carboxylic acid ester copolymer is a copolymer of ethylene and an unsaturated carboxylic acid ester. The said copolymer may contain only 1 type of unsaturated carboxylic acid ester structural unit, and may contain 2 or more types. Examples of the unsaturated carboxylic acid constituting the unsaturated carboxylic acid ester structural unit include 4 carbon atoms such as acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic acid anhydride, fumaric acid, crotonic acid, maleic acid, maleic anhydride, etc. And unsaturated carboxylic acids of ~8. In particular, acrylic acid or methacrylic acid is preferred.

Further, the unsaturated carboxylic acid ester structural unit contained in the ethylene-unsaturated carboxylic acid ester copolymer is preferably an unsaturated carboxylic acid alkyl ester. The number of carbon atoms in the alkyl moiety of the alkyl ester is preferably 1 to 12, more preferably 1 to 8, and still more preferably 1 to 4. Examples of the alkyl moiety include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, 2-ethylhexyl, isooctyl, and the like. Specific examples of the unsaturated carboxylic acid alkyl ester include methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, dimethyl maleate, maleic acid. Alkyl (meth)acrylates, such as diethyl, are mentioned.

When the total amount of the constituent units constituting the ethylene-unsaturated carboxylic acid ester copolymer in 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 is 5 mass. % Or more and 40% by mass or less are preferable, more preferably 7% by mass or more and 40% by mass or less, and particularly preferably 8% by mass or more and 40% by mass or less. When the content ratio of the structural unit derived from an unsaturated carboxylic acid ester is less than or equal to the above upper limit, it is preferable from the viewpoint of film processability. In addition, it is preferable from the viewpoint of shrinkage when the content ratio of the structural unit derived from an unsaturated carboxylic acid ester is equal to or greater than the lower limit.

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

In addition, MFR is a value measured at 190°C and a load of 2160 g by a method in accordance with JIS K7210-1999.

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

In addition, the melting point is a melting temperature measured with a current scanning calorimeter (DSC) in accordance with JIS-K7121 (1987).

The content of the resin (B) in the resin composition for a dicing film substrate is 10 parts by mass or more and less than 70 parts by mass, and 10 parts by mass or more and 60 It is preferably not more than 20 parts by mass, and more preferably not more than 50 parts by mass. When the content of the resin (B) is 10 parts by mass or more, the effect of improving the thermal contraction rate by the resin (B) is exhibited, and when it is less than 70 parts by mass, there is a low possibility that the strength of the dicing film base material will be insufficient.

1-3. Other polymers and additives

To the resin composition for a dicing film base material, other polymers and various additives may be added as necessary within the range not impairing the effects of the present invention. Examples of other polymers include polyamides, polyurethanes, and ionomers of binary copolymers. These other polymers can be blended in a ratio of, for example, 20 parts by mass or less with respect to 100 parts by mass of the total of the resin (A) and the resin (B). As an example of an additive, an antistatic agent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a pigment, a dye, a lubricant, an anti-blocking agent, an antistatic agent, a flame retardant, an antibacterial agent, a flame retardant, a flame retardant aid, a crosslinking agent, a crosslinking aid, a foaming agent, a foaming agent Auxiliaries, inorganic fillers, fiber reinforcements, etc. are mentioned.

1-4. Properties of resin composition

The resin composition of the present invention has a Vicat softening point specified in JIS K7206-1999 of less than 50°C, preferably 25°C or more and less than 50°C. When the Vicat softening point of the resin composition is less than 50°C, the thermal contraction rate is improved, and when it is 25°C or more, the resin composition can be processed into a film.

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

In addition, MFR is a value measured at 190°C and a load of 2160 g by a method in accordance with JIS K7210-1999.

Although there is no restriction|limiting in particular in the degree of neutralization of a resin composition, 10%-85% are preferable, and 15%-82% are more preferable. When the degree of neutralization of the resin composition is 10% or more, the chip-dividing property can be further improved, and when it is 85% or less, the film is excellent in moldability. The degree of neutralization of the resin composition basically depends on the degree of neutralization of the ionomer (A) and its content, and can be calculated by the following formula. (Degree of neutralization of resin composition) = (degree of neutralization of ionomer (A)) x (ratio of ionomer (A) in resin composition)

Therefore, when the neutralization degree of the ionomer (A) is low, the content thereof is slightly increased, or when the neutralization degree of the ionomer (A) is high, the neutralization degree of the resin composition can be adjusted by reducing the content. have.

Further, in the resin composition of the present invention, the heat shrinkage at 80°C of the film processed to a thickness of 100 μm 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 suitably used for production of a dicing film capable of eliminating sagging by a heat shrink process. The upper limit of the heat shrinkage rate is not particularly limited, but it is preferably 20% or less from the viewpoint of reducing the defective rate in a post-process (pickup process) after heat shrink.

In addition, in this application, the thermal contraction rate at 80 degreeC is a value measured by the following method.

The resin composition film was cut into a thickness of 100 µm and a width direction of 25 mm x a length direction of 150 mm, followed by marking at 100 mm between marks to obtain a test piece sample. It puts it on the glass plate which was crushed with starch, heated for 2 minutes on a hot plate of 80 degreeC, and measured between the mark lines of the film after heating, and the shrinkage ratio (%) was computed from the following formula.

Shrinkage rate (%) = 100㎜-Distance between marks after contraction (㎜) / 100㎜ × 100

1-5. Manufacturing method of resin composition

The resin composition for a dicing film base material can be obtained by mixing a resin (A) and a resin (B), as well as other polymers or additives as necessary. As described above, the resin composition of the present invention has a Vicat softening point of less than 50°C as defined in JIS K7206-1999, so that the Vicat softening point of the resin composition is less than 50°C, so that the resin (A) and the resin ( B) Select the type or amount of additives according to your wishes.

Although there is no restriction|limiting in particular in the manufacturing method of a resin composition, For example, it can obtain by melt-kneading after dry blending all components.

2. Dicing film base

A second aspect of the present invention is a dicing film substrate including at least one layer containing the resin composition for a dicing film substrate described above. 1A and 1B are cross-sectional views showing one embodiment of the dicing film substrate 10 of the present invention. FIG. 1A is a single-layer dicing film substrate composed of only the first resin layer 1 containing the resin composition for dicing film substrates described above, and FIG. 1B includes the resin composition for dicing film substrates described above. It is a multilayer dicing film base material in which the 1st resin layer 1 which is said and the 2nd resin layer 2 containing another resin or resin composition are laminated|stacked.

The strength of the dicing film base material of the present invention is preferably in the range of 5 MPa or more and 15 MPa or less, and more preferably 6 MPa or more and 12 MPa or less. When the 25% modulus is 5 MPa or more, the chip division property (strength) as a dicing film base material is excellent, and when it is 15 MPa or less, the expandability is excellent.

The modulus in the present invention is in accordance with JIS K7127-1999, with respect to the MD direction (Machine Direction: machine axial direction) and TD direction (Transverse Direction: orthogonal direction) of the dicing film substrate, test speed: 500 mm /min, test piece: width 10 mm x length 200 mm, between chuck: 100 mm under the condition of the film strength (25% modulus or 50% modulus) at 25% or 50% elongation distance to be.

The thermal contraction rate at 80°C of the dicing film base material of the present invention is preferably 6% or more and 20% or less, and more preferably 7% or more. If the heat shrinkage at 80°C is 6% or more, the heat shrink characteristic (resolves sagging) as a dicing film base material is excellent, and if it is less than 20%, the defect rate in the post-process (pickup process) after the heat shrink is excellent. Do.

In addition, in this application, the thermal contraction rate at 80 degreeC is a value measured by the following method.

The dicing film base material was cut into a thickness of 100 µm and a width direction of 25 mm x a length direction of 150 mm, and marking was performed at 100 mm between marks to obtain a test piece sample. It is placed on a glass plate in which starch is crushed, heated on a hot plate at 80° C. for 2 minutes, and measured between the marked lines of the film after heating, and the shrinkage percentage (%) is calculated from the following equation.

Shrinkage rate (%) = 100㎜-Distance between marks after contraction (㎜) / 100㎜ × 100

2-1. First resin layer

The first resin layer is the resin composition for a dicing film base material described above, that is, 30 parts by mass or more and 90 parts by mass or less of the ionomer (A) of an ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer, and an ethylene-based copolymer. The mixture (B) contains 10 parts by mass or more and 70 parts by mass or less (however, the total of component (A) and component (B) is 100 parts by mass), and the Vicat softening point specified by JIS K7206-1999 is less than 50°C. , It is a layer containing the resin composition for a dicing film base material. Moreover, the 1st resin layer may be a layer which consists of the said resin composition for dicing film base materials. Such a resin composition layer is excellent in balance between strength and heat shrinkage.

When the dicing film base material has a single layer structure, the content of the ionomer (A) of the resin composition as a raw material is 70 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 30 parts by mass. It is preferable that the content of the ionomer (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 (however, component (A) and component ( It is more preferable that the sum of B) is 100 parts by mass). Thus, by using the resin composition having a high ratio of the ionomer (A), even if it is a single layer, the necessary strength as a dicing film base material is achieved.

On the other hand, when the dicing film base material has a multilayer structure, the resin composition used as the raw material for the first resin layer is specifically based on the ratio of the ionomer (A) and the copolymer (B) as long as it is the resin composition of the present invention described above. There is no limitation, and the content of the ionomer (A) may be 30 parts by mass or more and 90 parts by mass or less, and the content of the ethylene-based copolymer (B) may be 10 parts by mass or more and 70 parts by mass or less.

2-2. 2nd resin layer

The second resin layer is a layer containing a resin (C) or a layer made of a resin (C), and the resin (C) is particularly limited as long as it is a resin having high adhesion to the resin composition constituting the first resin layer. There is no. By laminating the second resin layer containing the resin (C) (or consisting of the resin (C)) with the first resin layer, without causing a problem of delamination, while increasing the strength of the dicing film substrate, and It becomes possible to maintain the balance of chip division and expandability required for a dicing film.

<Resin (C)>

Resin (C) in the present invention is an ethylene-unsaturated carboxylic acid-based copolymer (hereinafter, also referred to simply as ``copolymer (C)'') and an ionomer of the ethylene-unsaturated carboxylic acid-based copolymer (hereinafter, only It is preferably at least one selected from the group consisting of "ionomer (C)"). The ionomer of the ethylene-unsaturated carboxylic acid-based copolymer used as the resin (C) is one in which a part or all of the carboxyl groups of the ethylene-unsaturated carboxylic acid-based copolymer is neutralized with a metal (ion).

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

The copolymer (C) or the ethylene-unsaturated carboxylic acid-based copolymer constituting the ionomer (C) is at least a binary copolymer in which ethylene and an unsaturated carboxylic acid are copolymerized, and a third copolymerization component is It may be a copolymerized ternary or more polyvalent copolymer. In addition, the ethylene-unsaturated carboxylic acid-based copolymer may be used singly or two or more ethylene-unsaturated carboxylic acid-based copolymers may be used in combination.

Examples of unsaturated carboxylic acids constituting the ethylene-unsaturated carboxylic acid binary copolymer include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, maleic acid, maleic anhydride, etc. And unsaturated carboxylic acids having 4 to 8 carbon atoms. In particular, acrylic acid or methacrylic acid is preferred.

When the ethylene-unsaturated carboxylic acid-based copolymer (C) is a three-membered or more multi-component copolymer, a monomer (third copolymerization component) forming the multi-component copolymer may be included. As the third copolymerization component, an unsaturated carboxylic acid ester (e.g., methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, (Meth)acrylic acid alkyl esters such as dimethyl maleate and diethyl maleate), unsaturated hydrocarbons (e.g., propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, 1-hexene, etc.), Vinyl ester (e.g., vinyl acetate, vinyl propionate, etc.), oxides such as vinyl sulfuric acid or vinyl nitric acid, halogen compounds (e.g., vinyl chloride, vinyl fluoride, etc.), vinyl group-containing primary and secondary amine compounds, carbon monoxide And sulfur dioxide, and the like. As these copolymerization components, unsaturated carboxylic acid esters are preferable.

For example, when the ethylene-unsaturated carboxylic acid-based copolymer (C) is a ternary copolymer, a ternary copolymer of ethylene, an unsaturated carboxylic acid, and an unsaturated carboxylic acid ester, ethylene, an unsaturated carboxylic acid, and unsaturated Tertiary copolymers of hydrocarbons, etc. are suitably mentioned.

As the unsaturated carboxylic acid ester, an unsaturated carboxylic acid alkyl ester is preferable, and the number of carbon atoms in the alkyl moiety of the alkyl ester is preferably 1 to 12, more preferably 1 to 8, and still more preferably 1 to 4. Examples of the alkyl moiety include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, 2-ethylhexyl, isooctyl, and the like.

As a specific example of the unsaturated carboxylic acid ester, an unsaturated carboxylic acid alkyl ester having 1 to 12 carbon atoms in the alkyl moiety (e.g., methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, etc.) , Alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, and isobutyl methacrylate, alkyl maleic esters such as dimethyl maleate and diethyl maleate), and the like.

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

The form of the copolymer may be any of a block copolymer, a random copolymer, and a graft copolymer, or may be a binary copolymer or a ternary or more multipolymer. Among them, from the viewpoint of industrial availability, a graft copolymer of a binary random copolymer, a ternary random copolymer, a binary random copolymer, or a graft copolymer of a ternary random copolymer is preferable, and more preferably It is a binary random copolymer or a ternary random copolymer.

Specific examples of the ethylene/unsaturated carboxylic acid-based copolymer include binary copolymers such as ethylene/acrylic acid copolymers and ethylene/methacrylic acid copolymers, and ternary copolymers such as ethylene/methacrylic acid/isobutyl acrylate copolymers. Can be lifted. Further, commercially available products released as an ethylene-unsaturated carboxylic acid-based copolymer may be used, and for example, the Nucrel series (registered trademark) manufactured by Mitsui DuPont Polychemical 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. The copolymerization ratio (mass ratio) of the unsaturated carboxylic acid ester in the ethylene-unsaturated carboxylic acid-based copolymer is preferably 1% by mass to 20% by mass, 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, preferably 5% by mass or more. In addition, 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, from the viewpoint of preventing blocking and fusion.

In the ionomer (C) used as the resin (C) in the present invention, it is preferable that the carboxyl group contained in the ethylene-unsaturated carboxylic acid-based copolymer is crosslinked (neutralized) at an arbitrary ratio with a metal ion. Metal ions used for neutralization of acid groups include metal ions such as lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions, zinc ions, magnesium ions, and manganese ions. Among these metal ions, magnesium ions, sodium ions and zinc ions are preferable, sodium ions and zinc ions are more preferable, and zinc ions are particularly preferable from the ease of availability of industrial products.

Metal ions may be used alone or in combination of two or more.

The degree of neutralization of the ethylene-unsaturated carboxylic acid-based copolymer in the ionomer (C) is preferably 10% to 85%, and more preferably 15% to 82%. When the degree of neutralization is 10% or more, the chip-dividing property can be further improved, and when it is 85% or less, the workability and moldability of the film are excellent.

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

The melt flow rate (MFR) of the resin (C) is preferably in the range of 0.2 g/10 min to 20.0 g/10 min, more preferably 0.5 g/10 min to 20.0 g/10 min, and 0.5 g/10 min. -18.0g/10min is more preferable. When the melt flow rate is within the above range, it is advantageous when forming a film.

In addition, MFR is a value measured at 190°C and a load of 2160 g by a method in accordance with JIS K7210-1999.

It is preferable that the resin (C) has a Vicat softening point of 50°C or more and 100°C or less. The strength and heat resistance of the dicing film base material can be improved by laminating a resin having a high Vicat softening point as a second resin layer on the first resin layer made of a resin composition having a Vicat softening point of less than 50°C.

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

<Other polymers and additives>

Various additives and other resins may be added to the resin (C) constituting the second resin layer as necessary within the range not impairing the effects of the present invention. As an example of the additive, an antioxidant, a heat stabilizer, a light stabilizer, a UV absorber, a pigment, a dye, a lubricant, an anti-blocking agent, an antistatic agent, a flame retardant, an antibacterial agent, a flame retardant, a flame retardant aid, a crosslinking agent, a crosslinking aid, a foaming agent, a foaming aid, Inorganic fillers, fiber reinforcements, and the like. From the viewpoint of preventing heat fusion, a small amount of the additive may be added.

2-3. Floor composition

In the dicing film base material of the present invention, a single-layer structure composed of only the first resin layer 1 (Fig. 1A), and a multilayer including the first resin layer 1 and the second resin layer 2 There is a configuration (Fig. 1B). The multi-layered dicing film base material is not particularly limited as long as it includes the two layers, but from the viewpoint of preventing delamination, the first resin layer and the second resin layer are directly laminated. desirable.

The dicing film base material of a multilayer structure may be a multilayer structure which becomes three or more layers. For example, a structure in which a second resin layer is provided in a place in which a plurality of sheets molded using a resin composition constituting the first resin layer are stacked may be stacked, or a second resin layer is sandwiched by two first resin layers. It may be a configuration. Moreover, in addition to the 1st resin layer and the 2nd resin layer, the structure which laminated|stacked another resin layer may be sufficient.

Representative examples of resins constituting the other resin layer laminated on the dicing film substrate of the present invention include linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), ethylene/α-olefin copolymer, and polypropylene. , And an ethylene/vinyl ester copolymer selected from a single substance or a blend comprising an arbitrary plurality.

Further, the other resin layer to be laminated may be a functional layer (eg, an adhesive sheet), or a base material such as a polyolefin film (or sheet), a polyvinyl chloride film (or sheet), or the like. The substrate may have either a single layer or a multilayer structure. In the present invention, these substrates are also referred to as "dicing film substrates".

In order to improve the adhesion of the dicing film base material surface, a known surface treatment such as corona discharge treatment may be applied to the surface of the dicing film base material.

Further, from the viewpoint of improving heat resistance, electron beam irradiation may be performed on the first resin layer, the second resin layer or other resin layer, or the dicing film base material as necessary.

2-4. Method for manufacturing dicing film substrate

As a manufacturing method of a single-layer dicing film base material, a method of processing the resin composition for dicing films into a film by a known method is mentioned. Although there is no particular limitation on the method of processing the resin composition into a film, for example, a film can be formed by various molding methods such as a conventionally known T die-cast molding method, a T die nip molding method, an inflation molding method, an extrusion lamination method, and a calender molding method. Can be manufactured.

As a manufacturing method of the multilayer dicing film base material, the resin composition constituting the first resin layer and the resin (C) constituting the second resin layer are processed into a film by a known method, followed by lamination. have. Although there is no particular limitation on the method of processing the resin composition or the resin into a film, for example, various molding methods such as conventionally known T die cast molding method, T die nip molding method, inflation molding method, extrusion lamination method, and calender molding method, Films can be produced.

In addition, the multilayer dicing film base material can be produced by providing the resin composition constituting the first resin layer and the resin (C) constituting the second resin layer to, for example, a coextrusion laminate.

For example, in the case of laminating the resin composition constituting the first resin layer on the surface of the film of the resin (C) serving as the second resin layer by a T-die film molding machine or an extrusion coating molding machine, the second resin layer and In order to improve the adhesiveness of, it may be formed through an adhesive resin layer by a coextrusion coating molding machine. As such an adhesive resin, a single or arbitrary blends selected from the above-described various ethylene copolymers or unsaturated carboxylic acid grafts thereof can be exemplified as a representative example.

In addition, as a molding example of the dicing film base material of the present invention, a T-die film molding machine or an extrusion coating molding machine is used to form a first resin layer on the surface of the film of the resin (C) serving as the second resin layer. The method of forming a multilayer body by heat bonding a resin composition is mentioned.

In addition, a method of forming a layer made of a resin composition serving as the first resin layer on the film of the resin (C) serving as the second resin layer has been described, but on the contrary, the film of the resin composition serving as the first resin layer On the top, the dicing film base material of the present invention can be produced by forming a layer from the resin (C) serving as the second resin layer, or by providing a first resin or a second resin layer on another resin layer. have.

The thickness of the dicing film base material is not particularly limited, but considering use as a constituent member of the dicing film, it is preferably 65 µm or more from the viewpoint of frame retention during dicing and 200 µm or less from the viewpoint of expandability. Do. In addition, the thickness of each resin layer constituting the multilayer dicing film base material is not particularly limited as long as the total does not exceed the above thickness of the dicing film base material, but all of the first resin layer and the second resin layer are 30 μm. It is preferable that it is more than 100 micrometers, and it is preferable that the ratio of the thickness of a 1st resin layer and a 2nd resin layer is 30/70-70/30.

3. Dicing film

A 3rd aspect of this invention is a dicing film provided with the dicing film base material of this invention mentioned above, and the adhesive layer laminated on at least one surface thereof. 2A and 2B are cross-sectional views showing one embodiment of the dicing film 20 of the present invention. The dicing film 20 shown in FIG. 2A has a dicing film base 10 composed of only the first resin layer 1 and an adhesive layer 11 provided on the surface thereof, and a dicing film shown in FIG. 2B ( 20) has a dicing film base material 10 including a first resin layer 1 and a second resin layer 2, and an adhesive layer 11 provided on the surface thereof.

As for the dicing film, the structure in which the adhesive layer was formed in the outermost layer is preferable. The adhesive layer is disposed on the surface of the dicing film base material. A dicing film is affixed to a semiconductor wafer via this adhesive layer, and dicing of a semiconductor wafer can be performed. In addition, in FIG. 2B, although the adhesive layer 11 is arrange|positioned on the 1st resin layer 1 which consists of the resin composition for a dicing film base material of this invention, this invention is not limited to this structure. The adhesive layer 11 may be disposed on the second resin layer 2 (or another resin layer).

<Adhesive layer>

The dicing film of the present invention includes the dicing film substrate of the present invention and an adhesive layer provided on one side of the dicing film substrate, and a semiconductor wafer to be subjected to dicing is attached and fixed to the adhesive layer. Although the thickness of the adhesive layer depends on the type of the adhesive, it is preferably 3 to 100 µm, and more preferably 3 to 50 µm.

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, a conventionally known pressure-sensitive adhesive can be used. Examples of the pressure-sensitive adhesive include rubber, acrylic, silicone, and polyvinyl ether pressure-sensitive adhesives; Radiation curable adhesives; And a heat-foaming type pressure-sensitive adhesive. Among them, in consideration of the peelability of the dicing film from the semiconductor wafer, etc., it is preferable that the adhesive layer contains an ultraviolet curable adhesive.

Examples of the acrylic pressure-sensitive adhesive capable of constituting the pressure-sensitive adhesive layer include a homopolymer of a (meth)acrylic acid ester, and a copolymer of a (meth)acrylic acid ester and a copolymerizable monomer. Specific examples of the (meth)acrylic acid ester include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isononyl (meth)acrylate, and the like. (Meth)acrylic acid alkyl ester, (meth)acrylic acid hydroxyethyl, (meth)acrylate hydroxybutyl, (meth)acrylic acid hydroxyalkyl ester such as hydroxyhexyl, (meth)acrylic acid glycidyl ester Etc. are included.

Specific examples of the copolymerizable monomer with (meth)acrylic acid ester include (meth)acrylic acid, itaconic acid, maleic anhydride, (meth)acrylic acid amide, (meth)acrylic acid N-hydroxymethylamide, (meth)acrylic acid alkylamino Alkyl esters (eg, dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate, etc.), vinyl acetate, styrene, acrylonitrile, and the like are included.

The ultraviolet curable adhesive capable of constituting the adhesive layer is not particularly limited, but the acrylic adhesive, an ultraviolet curing component (a component capable of adding a carbon-carbon double bond to the polymer side chain of the acrylic adhesive), and a photopolymerization initiator Contains. In addition, additives, such as a crosslinking agent, a tackifier, a filler, an anti-aging agent, and a colorant, may be added to the ultraviolet curable adhesive, if necessary.

The ultraviolet curing component contained in the ultraviolet curable pressure-sensitive adhesive is, for example, a monomer, oligomer, or polymer that has a carbon-carbon double bond in a molecule and can be cured by radical polymerization. Specific examples of the ultraviolet curing component include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexanediol (meth) acrylate, and neo Esters of (meth)acrylic acid and polyhydric alcohols such as pentyl glycol di (meth) acrylate and dipentaerythritol hexa (meth) acrylate, and oligomers thereof; 2-propenyldi-3-butenylcyanurate, 2-hydroxyethylbis(2-acryloxyethyl)isocyanurate, tris(2-methacryloxyethyl)isocyanurate, tris(2- Isocyanurates, such as methacryloxyethyl) isocyanurate, etc. are contained.

Specific examples of the photopolymerization initiator contained in the ultraviolet curable pressure-sensitive adhesive include benzoin alkyl ethers such as benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether, and aromatic ketones such as α-hydroxycyclohexylphenyl ketone, Aromatic ketals such as benzyl dimethyl ketal, thioxanthones such as polyvinyl benzophenone, chloro thioxanthone, dodecyl thioxanthone, dimethyl thioxanthone, and diethyl thioxanthone, and the like.

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

It is preferable to affix a separator to the surface of the adhesive layer of the dicing film of this invention. By attaching the separator, the surface of the adhesive layer can be kept smooth. In addition, handling and transportation of the film for semiconductor manufacturing becomes easy, and label processing on the separator is also possible.

The separator may be paper or a synthetic resin film such as polyethylene, polypropylene, or polyethylene terephthalate. Further, on the surface of the separator in contact with the adhesive layer, a release treatment such as silicone treatment or fluorine treatment may be performed as necessary in order to increase the peelability from the adhesive layer. The thickness of the separator is usually 10 to 200 µm, preferably about 25 to 100 µm.

<Method of manufacturing dicing film>

When manufacturing the dicing film of the present invention, dicing the pressure-sensitive adhesive using a known method, for example, a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, a knife coater, a spray coater, etc. A method of directly applying to a film substrate, or a method of applying the pressure-sensitive adhesive on a release sheet by the aforementioned known method to provide an adhesive layer, and then attaching it to a surface layer of a dicing film substrate to transfer the adhesive layer, or the like can be used.

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

Further, the layer of the pressure-sensitive adhesive composition may be heat-crosslinked as necessary to form an adhesive layer.

Moreover, you may affix a separator on the surface of an 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 resin (A), zinc (Zn) ion neutralization ionomer of ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer or ethylene/unsaturated carboxylic acid-based copolymer shown in Table 1 below (hereinafter referred to as ``ionomer'' I should) prepared.

2. Resin (B)

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

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

MFR (melt flow rate) in Table 2 is a value measured at 190°C and a load of 2160 g in accordance with JIS K7210-1999.

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

3. Resin (C)

As resin (C), ionomer 1 (IO-1) (same as used as resin (A)) was prepared (see Table 1 above).

(Example 1)

The resin (A) and resin (B) of the ratio (mass %) shown in Table 3 were dry-blended. Next, the dry blended mixture was put into the resin inlet of a 40 mmφ single screw extruder, and melt-kneaded at a die temperature of 200°C to obtain 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 introduced into each extruder using a two-layer, two-layer 40 mmφ T-die film molding machine, and a processing temperature of 240°C. It was molded under conditions to prepare a two-layer T-die film having a thickness of 100 μm. In the laminated film having a thickness of 100 µm having a two-layer structure, the thickness ratio of the first layer and the second layer was 60/40.

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

A resin composition for a first resin layer was prepared in the same manner as in Example 1 except that the types and amounts of the resin (A) and the resin (B) were changed as shown in Table 3 or Table 4. Next, as in Example 1, except that the thickness of the first resin layer and the second resin layer was changed as shown in Table 3 or Table 4, a laminated film including the first resin layer and the second resin layer was prepared. Was prepared.

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

A resin composition for a first resin layer was prepared in the same manner as in Example 1 except that the types and amounts of the resin (A) and the resin (B) were changed as shown in Table 3 or Table 4. Next, using the prepared resin composition, a one-layer T-die film having a thickness of 100 μm was prepared in the same manner as in Example 1 without using the resin (C).

About the resin composition for the 1st resin layer and film obtained in the said Example and the comparative example, it evaluated by the following method. The evaluation results are shown in Table 3 or Table 4.

(1) the degree of neutralization of the resin composition

The degree of neutralization was calculated from the degree of neutralization of the resin (A) and its content.

(2) MFR of the resin composition

MFR was measured under a load of 190°C and 2160 g in accordance with JIS K7210-1999.

(3) Vicat softening temperature of resin composition

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

(4) 80℃ shrinkage

The resin composition was molded on a film having a thickness of 100 µm, cut into 25 mm in width direction x 150 mm in length direction, and marked at 100 mm between marks to obtain a test piece sample. On the glass plate, starch powder (Nikka Co., Ltd. product, Nikkari powder) for preventing film adhesion was crushed, a test piece sample was placed thereon, and heated at 80°C for 2 minutes on a hot plate of a press molding machine. The distance between the marked lines of the film after heating was measured, and the shrinkage ratio (%) was calculated from the following equation.

Shrinkage rate (%) = 100㎜-Distance between marks after contraction (㎜) / 100㎜ × 100

(5) Tensile test (modulus)

The dicing film base material was cut into a strip shape of 10 mm width, and it was set as a measurement object. In accordance with JIS K7127, under the conditions of a test piece: 10 mm wide x 200 mm long, and a chuck: 100 mm, the film strength at 25% and 50% of the elongation distance in each of the MD and TD directions of the measurement object (25%) Modulus and 50% modulus) were measured, respectively. In addition, the test speed was 500 mm/min.

30 parts by mass or more and 90 parts by mass or less of resin (A), which is an ionomer of ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer (tertiary copolymer), and 10 parts by mass or more of resin (B), which is an ethylene-based copolymer The dicing film base material of Examples prepared using a resin composition containing 70 parts by mass or less and having a Vicat softening point of less than 50°C was excellent in both heat (80°C) shrinkage and strength. On the other hand, in the resin composition of Comparative Example 1 using the ionomer of the binary copolymer, the Vicat softening point exceeded 50°C. The dicing film base material produced by using such a resin composition had a low heat shrinkage rate. Dicing film substrates containing resin (A) and resin (B), but prepared using the resin compositions of Comparative Examples 2 and 3 in which the Vicat softening point exceeded 50°C, as in Comparative Example 1, had low heat shrinkage. .

Dies of Examples 9 to 11 using resin compositions containing 70 parts by mass or more and 90 parts by mass or less resin (A) and 30 parts by mass or more and 10 parts by mass or less resin (B) and having a Vicat softening point of less than 50°C The sinking film base material exhibited sufficient strength and heat shrinkability at the same time even though it was a single layer.

The resin compositions of Comparative Examples 4 and 5 containing resin (A) in an amount exceeding 90 parts by mass and resin (B) in an amount of less than 10 parts by mass had a Vicat softening point exceeding 50°C. The dicing film base material produced by using such a resin composition had high strength, but low heat shrinkage. Similarly, the dicing film substrates of Comparative Examples 6 to 10 using the ionomer as the first resin layer also exhibited high strength, but had a low thermal contraction rate. In particular, ionomer 2 used in Comparative Example 7 had a Vicat softening point of less than 50°C, but had a low heat shrinkage rate.

From these results, in order to obtain a dicing film base material in which high strength and high heat shrinkage are compatible, the content of the resin (A), which is an ionomer of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer of the resin composition as a raw material, is It is understood that it is important that the content of the resin (B), which is 30 parts by mass or more and 90 parts by mass or less, is 10 parts by mass or more and 70 parts by mass or less, and that the Vicat softening point is less than 50°C.

This application claims priority based on Japanese Patent Application No. 2018-149562 for an application on August 8, 2018. All of the contents described in the application specification are incorporated in the specification of the present application.

The dicing film of the present invention can be suitably used in a method for manufacturing a semiconductor device in which a heat shrink process is performed in addition to a dicing process and an expansion process for dividing a semiconductor wafer into chips. In particular, since the dicing film of the present invention has both high strength and high heat shrinkability, a stealth die in which a greater stress is applied to the dicing film than in conventional methods (blade dicing method, laser ablation method, etc.) in the expansion process. It can be suitably used for a manufacturing method employing the Sing (registered trademark) method. By using the dicing film of the present invention, the interval between the chips after division is made uniform, product defects in subsequent steps are reduced, and the semiconductor device can be manufactured with a high yield.

1 first resin layer
2 second resin layer
10 Dicing film base
11 Adhesive layer
20 dicing film

Claims (10)

30 parts by mass or more and 90 parts by mass or less of ionomer (A) of ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer;
It contains 10 parts by mass or more and 70 parts by mass or less (however, the sum of the components (A) and (B) is 100 parts by mass) of the ethylene-based copolymer (B),
A resin composition for a dicing film base material having a Vicat softening point specified in JIS K7206-1999 less than 50°C. The method of claim 1,
The resin composition for a dicing film base material wherein the ionomer (A) of the ethylene/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer has a Vicat softening point specified in JIS K7206-1999 of 25°C or more and 60°C or less. The method according to claim 1 or 2,
The resin composition for a dicing film base material, wherein the ethylene-based copolymer (B) is a resin having a Vicat softening point of 50° C. or less specified in JIS K7206-1999, or a resin having no Vicat softening point. The method according to any one of claims 1 to 3,
The resin composition for a dicing film base material, wherein the 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. The method according to any one of claims 1 to 4,
Dicing of the ethylene-based copolymer (B) having a melt flow rate (MFR) of 0.2 g/10 min to 30.0 g/10 min measured at 190° C. and a load of 2160 g by a method in accordance with JIS K7210-1999 Resin composition for a film base. The method according to any one of claims 1 to 5,
A dicing film having a melt flow rate (MFR) of 0.1 g/10 min to 50 g/10 min at 190°C and a load of 2160 g of the resin composition for a dicing film base material according to JIS K7210-1999 Resin composition for base material. A dicing film substrate comprising at least one layer containing the resin composition for dicing film substrates according to any one of claims 1 to 6. The method of claim 7,
A first resin layer comprising the resin composition for a dicing film substrate according to any one of claims 1 to 6, and
A dicing film substrate comprising a second resin layer comprising a resin (C) laminated on the first resin layer. The method of claim 8,
The dicing film substrate, wherein the resin (C) is at least one selected from the group consisting of an ethylene-unsaturated carboxylic acid-based copolymer and an ionomer of the ethylene-unsaturated carboxylic acid-based copolymer. The dicing film substrate according to any one of claims 7 to 9, and
A dicing film, characterized in that it has an adhesive layer laminated on at least one surface of the dicing film substrate.

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