KR20200045444A - Gas film for dicing - Google Patents

Abstract

An object of the present invention is to provide a gas film for dicing having high recoverability by heat and excellent rack recoverability. Another object of the present invention is to provide a gas film for dicing in which the dicing film is uniformly stretched even when expansion is performed under low temperature conditions.
As a gas film for dicing comprising a layered structure in the order of surface layer / intermediate layer / bilayer, the surface layer and the bilayer are made of a resin composition containing a polyethylene-based resin, and the intermediate layer is made of a resin composition containing a polyurethane-based resin, for dicing Gas film.

Description

Gas film for dicing

The present invention relates to a substrate film for dicing, which is used by dicing and fixing a semiconductor wafer to a semiconductor wafer.

As a method of manufacturing a semiconductor chip, there is a method of manufacturing a semiconductor wafer in a large area in advance, then dicing (cutting off) the semiconductor wafer into a chip shape, and finally picking up the diced chip. As a method of cutting a semiconductor wafer, in recent years, stealth dicing is known in which a semiconductor wafer is cut (segmented) without contacting the semiconductor wafer using a laser processing apparatus.

As a method of improving the cutability (splitting property) of a semiconductor wafer by stealth dicing, by expanding under a low temperature condition of -15 to 5 ° C, the stretching of the die bond film provided on the dicing tape is suppressed. , Wafer processing tapes in which a semiconductor wafer and a die-bonding film are cut (segmented) in a good manner are known as a method of simultaneously increasing the stress (Patent Documents 1 and 2).

Patent Literature 1: Patent Publication 2015-185584 Patent Document 2: Patent Publication No. 2015-185591

An object of the present invention is to provide a gas film for dicing having high recoverability by heat and excellent rack recoverability.

Another object of the present invention is to provide a gas film for dicing that is uniformly stretched even when expansion is performed under low temperature conditions.

The present invention further performs expansion under low-temperature conditions (-15 to 5 ° C) and high-speed conditions when the semiconductor wafer and die bond layer are cut (divided) after stealth dicing (laser dicing). It is also an object of the present invention to provide a gas film for dicing that elongates satisfactorily.

In the semiconductor manufacturing line, it is required to temporarily store a sheet (a dicing film containing a base film for dicing) in a product during processing after the expand process in a rack. At this time, if the sheet was left with sagging, it tended to lead to problems such as unsuccessful storage in the rack, or product collisions and defects. The rack is a name used in the art, and is also called a zipper or a case.

In order to solve this, it is necessary to eliminate the sagging of the sheet after the expand process. As a method, a heat shrink technology (heat shrinkage restoration technology) exists. This is to shrink the portion by heating the sagging portion generated by the expand process to eliminate the sagging (high recovery rate due to heat shrinkage).

For example, even when the expansion is performed under a low temperature condition of -15 to 5 ° C, the dicing film is uniformly stretched, and it is required that the semiconductor wafer is cut well.

Further, for example, after stealth dicing, in addition to the low-temperature conditions, even when expansion is performed under high-speed conditions, the dicing film elongates favorably and the semiconductor wafer and die-bond layer are cut (segmented) satisfactorily. Is required.

The present inventor has conducted earnest research to solve the above problems.

The gas film for dicing includes a structure laminated in the following surface layer / middle layer / bilayer order, and by using a polyurethane-based resin as the intermediate layer, a sheet after the expansion process (dicing including a gas film for dicing) It has been found that sagging of the film) is satisfactorily eliminated by a heat shrink technique (heat shrinkage restoration technique).

It has been found that the dicing film elongates uniformly even when the dicing film is expanded under low temperature conditions. It was found that the dicing film elongated satisfactorily even when the base film for dicing was expanded under high-speed conditions in addition to low-temperature conditions.

Item 1.

A substrate film for dicing comprising a layered structure in the order of surface layer / intermediate layer / bilayer, wherein the surface layer and the two layers are made of a resin composition containing a polyethylene-based resin,

The intermediate layer is made of a resin composition containing a polyurethane-based resin,

Gas film for dicing.

Item 2.

According to claim 1,

A gas film for dicing, wherein the surface layer and / or the two layers are single layers or multiple layers.

Section 3.

The method according to claim 1 or 2,

The polyethylene-based resin, branched chain low density polyethylene (LDPE), straight chain low density polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer , Ethylene-butyl acrylate copolymer, ethylene-methyl methacrylate copolymer (EMMA), ethylene-methacrylic acid copolymer (EMAA), and at least one resin selected from the group consisting of ionomer resins Phosphorus, dicing gas film.

Item 4.

The method according to any one of claims 1 to 3,

A gas film for dicing, wherein the polyurethane-based resin is a thermoplastic polyurethane resin (TPU).

Clause 5.

The dicing film which provided the adhesive layer and the die bond layer in this order on the surface layer side of the base film for dicing in any one of said claim | item 1-4.

When the gas film for dicing of the present invention is used, recovery of the used dicing film to the rack can be performed more quickly and easily. That is, the gas film for dicing of the present invention has high recovery by heat, that is, heat shrinkability is satisfactorily exhibited, and rack recovery is excellent.

When the gas film for dicing of the present invention is used, even when expansion is performed under low temperature conditions, the dicing film is uniformly stretched.

When the substrate film for dicing of the present invention is used, for example, after stealth dicing, in the case of cutting (segmenting) a semiconductor wafer and a die bond layer, dicing film is performed even when expansion is performed under low temperature conditions and high speed conditions. It stretches well.

The present invention relates to a gas film for dicing.

In addition, the present invention relates to a dicing film in which an adhesive layer and a die bond layer are provided in this order on a base film for dicing.

(1) Gas film for dicing

The gas film for dicing of the present invention,

Characterized in that it comprises a layered structure in the order of the surface layer / middle layer / bilayer.

It is preferable that the surface layer and / or the double layer is a single layer or a double layer.

Hereinafter, each layer constituting the gas film for dicing of the present invention will be described in detail.

(1-1) Surface layer

The surface layer is made of a resin composition containing a polyethylene-based resin.

As the polyethylene resin included in the surface layer, branched chain low density polyethylene (LDPE), straight chain low density polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylic At least one component selected from the group consisting of acrylate copolymers, ethylene-butyl acrylate copolymers, ethylene-methyl methacrylate copolymers (EMMA), ethylene-methacrylic acid copolymers (EMAA), and ionomer resins. It is preferable to use.

The surface layer is made of a resin composition containing at least one of these components, and thus has excellent expandability of the base film for dicing, that is, tensile properties of the substrate.

In addition, polypropylene-based resins may be blended to the extent that the effects of the present invention are not impaired.

The melt flow rate (MFR) at 190 ° C of the ethylene-vinyl acetate copolymer (EVA) should be about 30 g / 10 minutes or less, preferably about 20 g / 10 minutes or less, and about 15 g / 10 minutes or less Preferably, about 10 g / 10 minutes or less is even more preferable. By setting the MFR to 10 g / 10 minutes or less, the difference in viscosity from the intermediate layer can be suppressed, so that stable film formation can be achieved.

In addition, since the MFR of EVA facilitates extrusion of the resin, about 0.1 g / 10 minutes or more is preferable, and about 0.3 g / 10 minutes or more is more preferable.

The density of the EVA, a 0.9 ~ 0.96g / cm ³ degree is preferable, more preferably 0.92 ~ 0.94g / cm ³ or so.

The melt flow rate (MFR) at 190 ° C of the branched chain low-density polyethylene (LDPE) is preferably about 10 g / 10 minutes or less, more preferably about 6 g / 10 minutes or less. By setting the MFR to 10 g / 10 min or less, a difference in viscosity from the intermediate layer can be suppressed, and thus stable film formation can be achieved.

In addition, since the MFR of LDPE facilitates extrusion of the resin, about 0.1 g / 10 minutes or more is preferable, and about 0.3 g / 10 minutes or more is more preferable.

The density of LDPE is a 0.9 ~ 0.94g / cm ³ degree is preferable, more preferably 0.91 ~ 0.93g / cm ³ or so.

The melt flow rate (MFR) at 190 ° C of linear low-density polyethylene (LLDPE) is preferably about 10 g / 10 minutes or less, more preferably about 6 g / 10 minutes or less. By setting the MFR to 10 g / 10 min or less, a difference in viscosity from the intermediate layer can be suppressed, and thus stable film formation can be achieved.

In addition, since the MFR of LLDPE facilitates extrusion of the resin, about 0.1 g / 10 minutes or more is preferable, and about 0.3 g / 10 minutes or more is more preferable.

The density of LLDPE is a 0.9 ~ 0.94g / cm ³ degree is preferable, more preferably 0.91 ~ 0.93g / cm ³ or so.

Here, the melt flow rate (MFR) was obtained according to ISO 1133, and the density was obtained according to ISO 1183-1: 2004.

The surface layer may further contain an antistatic agent, if necessary. An antistatic agent that can be used in the surface layer can also be used in the second layer. As the antistatic agent used in the surface layer, known surfactants such as anionic, cationic, and nonionic surfactants can be selected, but among them, nonionic surfactants such as PEEA resin and hydrophilic PO resin are suitable for persistence and durability. Do.

When the surface layer contains an antistatic agent, the content of the antistatic agent is preferably about 5 to 25% by weight of the antistatic agent, and more preferably about 7 to 22% by weight of the resin composition of the surface layer. By blending the antistatic agent in the above range, the slipperiness of the surface layer in the case of being expanded together in contact with the expandable ring is not impaired.

Further, since the semiconductivity is effectively provided, static electricity generated can be quickly eliminated. For example, the gas film for dicing of the present invention containing an antistatic agent in the above-described range is preferable because the surface resistivity of the back surface thereof is about 10 ⁷ to 10 ¹² Ω / □.

An anti-blocking agent or the like may be further added to the surface layer. By adding an anti-blocking agent, blocking such as a case in which the gas film for dicing is wound in a roll form is suppressed, which is preferable. As the anti-blocking agent, inorganic or organic fine particles can be exemplified.

(1-2) Second floor

Like the surface layer, this layer is made of a resin composition containing a polyethylene-based resin.

A polyethylene resin used for the surface layer may be used, or a polyethylene resin different from the surface layer may be used.

In addition, if necessary, like the surface layer, an antistatic agent or an antiblocking agent may also be included.

In the gas film for dicing of the present invention, the surface layer and / or the two layers may be a single layer or a multilayer. The gas film for dicing of this invention can provide multiple layers of surface layers and / or two layers as needed.

When the superficial layer and / or the bilayer are made into a multi-layer, it is represented by the superficial layer-1, the superficial layer-2, the superficial layer-3, ... in order from the outermost layer side, and the bilayer-1, the bilayer-2 sequentially from the outermost layer side. , Two-layer-3, ...

(1-3) Middle floor

The intermediate layer is made of a resin composition containing a polyurethane-based resin (PU).

It is preferable that the PU is a thermoplastic polyurethane resin (TPU).

It is possible to improve the expandability by having the intermediate film made of a resin composition containing a polyurethane-based resin (PU) for the base film for dicing.

When the substrate film for dicing has an intermediate layer made of a resin composition containing a polyurethane-based resin (PU), for example, after stealth dicing, when cutting (segmenting) a semiconductor wafer and a die-bond layer, low temperature conditions and Even when the expansion is performed under high-speed conditions, the dicing film elongates satisfactorily.

(i) Polyurethane-based resin (PU)

As the polyurethane-based resin (PU), it is preferable to use a thermoplastic polyurethane resin (TPU). As a TPU, it is obtained by reacting a polyisocyanate, a polyol, and a chain extender, and is a block copolymer composed of a soft segment produced by the reaction of a polyol and polyisocyanate and a hard segment produced by the reaction of a chain extender and a polyisocyanate.

Examples of the polyisocyanate include diphenylmethane diisocyanate, hexamethylene diisocyanate, tolidine diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and the like. Of these, diphenylmethane diisocyanate and / or hexamethylene diisocyanate are preferred from the viewpoint of abrasion resistance of the thermoplastic polyurethane resin.

Examples of the polyol include polytetramethylene ether glycol, polyester polyol, lactone-based polyester polyol, and the like. Polyester polyol is obtained by the polycondensation reaction of dicarboxylic acid and diol.

Diols used in the production of polyester polyols include, for example, ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and the like. These are used alone or in combination.

Moreover, adipic acid, sebacic acid, etc. are mentioned as the dicarboxylic acid used for this invention, These are individually or in combination.

Among these polyols, polytetramethylene ether glycol is preferable because the thermoplastic polyurethane resin can obtain high rebound resilience. Moreover, it is preferable that the number average molecular weight of such a polyol is 1,000-4,000, and it is especially preferable that the number average molecular weight is 2,000-3,000.

In addition, examples of the chain extender include aliphatic straight-chain diols having 2 to 6 carbon atoms such as ethanediol, 1,4-butanediol, and 1,6-hexanediol, and 1,4-bis (hydroxyethoxy) benzene. Can be lifted. Amines such as hexamethylenediamine, isophoronediamine, tolylenediamine, and monoethanolamine can also be used in combination. Of these, aliphatic straight-chain diols having 2 to 6 carbon atoms are preferable from the viewpoint of abrasion resistance of the thermoplastic polyurethane resin.

The density of the thermoplastic polyurethane resin is about 1.1 ~ 1.5g / cm ³ are preferred, more preferably about 1.1 ~ 1.3g / cm ^3.

The thermoplastic polyurethane resin can be produced using a known method such as the one-shot method and the prepolymer method.

Examples of the PU include, for example, DIC COVESTRO POLYMER LTD. PANDEX, NIPPON MIRACTRAN CO., LTD. MIRACTRAN, and the like.

In the intermediate layer, in addition to the above-mentioned (i) PU, the resin composition constituting (ii) may include a polyethylene-based resin.

(ii) Polyethylene resin

As the polyethylene-based resin, a resin usable in the surface layer can be used.

A resin such as a polyethylene resin used in the surface layer may be used for the intermediate layer, or a resin different from the polyethylene resin used in the surface layer may be used. As the polyethylene-based resin, it is preferable to use an ethylene-methacrylic acid copolymer (EMAA) together with the PU.

The content ratio in the case of containing a polyethylene-based resin in the intermediate layer is preferably 0 to 80% by weight, and more preferably 0 to 70% by weight.

When the polyethylene-based resin is in the range of 0 to 80% by weight, the expandability of the base film for dicing, that is, the tensile property is good.

(1-4) Layer configuration of gas film for dicing

The gas film for dicing of this invention contains the structure laminated | stacked in order of surface layer / intermediate layer / bilayer.

The surface layer is a layer in contact with the adhesive layer as the wafer contact side.

The intermediate layer may form a layer (single layer) by each resin alone, a layer (single layer) by a mixture of resins, or a layer (multilayer) for each resin.

In the gas film for dicing of the present invention, it is preferable that the surface layer and / or the two layers are single layers or multiple layers. For the front and rear layers, LDPE, EVA, or the like may form a layer (single layer) with each resin, a layer (single layer) with a mixture of resins, or a layer (multilayer) for each resin.

The total thickness of the dicing gas film of the present invention is preferably about 50 to 300 μm, more preferably about 70 to 200 μm, and even more preferably about 80 to 150 μm. By setting the total thickness of the dicing base film to 50 μm or more, it becomes possible to protect the semiconductor wafer from impact when dicing the semiconductor wafer.

With respect to the total thickness of the base film for dicing, the ratio of the thickness of the surface layer and the two layers is preferably about 4 to 80%, more preferably about 10 to 60%.

With respect to the total thickness of the base film for dicing, the ratio of the thickness of the intermediate layer is preferably about 20 to 96%, more preferably about 40 to 90%.

As a specific example of the dicing gas film, a case where the total thickness of the dicing gas film is about 60 to 100 μm will be described.

The thickness of the surface layer and the bilayer is preferably about 2 to 44 μm each, and more preferably about 10 to 38 μm each. When the surface layer and the double layer are multi-layers, each layer may be formed within the above-mentioned thickness range as the total thickness.

The thickness of the intermediate layer is preferably about 12 to 96 μm, and more preferably about 24 to 80 μm. When the intermediate layer is a multi-layer, each layer may be formed within the above-mentioned thickness range as the total thickness.

3 types of 5 layers (Purple-1 / Purple-2 / Intermediate / Secondary-2 / Secondary-1)

In the example of making three types of five layers, as described above, the total thickness of the surface layer-1 and the surface layer-2 becomes the range of the thickness of the surface layer, and similarly, the total thickness of the two layer-1 and the two layer-2 is It becomes the range of thickness.

As the surface layer-1 and the surface layer-2, the same type of polyethylene-based resin may be used, or different types of polyethylene-based resin may be used.

The second layer-1 and the second layer-2 may use the same type of polyethylene-based resin, or may use different types of polyethylene-based resin.

When using the same type of polyethylene-based resin, for example, when using EVA, the EVA used for the surface layer-2 and the second layer-2 has a vinyl group content (VA) compared to the EVA used for the surface layer-1 and the second layer-1. It is preferable to use EVA having a high content).

In the surface layer-1 and the second layer-1, it is preferable to use EVA having a VA content of about 5 to 15% by weight, and it is more preferable to use EVA having about 7 to 13% by weight.

In the surface layer-2 and the second layer-2, it is preferable to use EVA having a VA content of about 15 to 33% by weight, and it is more preferable to use EVA having about 28 to 33% by weight.

In addition, from the viewpoint of MFR, it is preferable to use EVA having a higher melt flow rate (MFR) than EVA used for the surface layer-2 and the second layer-2.

In the surface layer-1 and the second layer-1, the MFR at 190 ° C of EVA is preferably about 0.1 g / 10 min to 10 g / 10 min, more preferably about 5 g / 10 min to 10 g / 10 min.

In the surface layer-2 and the layer-2, the MFR at 190 ° C of EVA is preferably about 10 g / 10 min to 40 g / 10 min, more preferably about 12 g / 10 min to 35 g / 10 min.

(2) Manufacturing method of gas film for dicing

The base / intermediate / bilayer gas film for dicing can be produced by multi-layer coextrusion molding of the resin composition for the surface, intermediate, and bilayers. Specifically, the resin composition for a surface layer, the resin composition for a middle layer, and the resin composition for a double layer can be produced by coextrusion molding so as to be laminated in the order of the surface layer / intermediate layer / bilayer.

In addition, when the surface layer and the double layer have a double layer structure, the resin composition for each surface layer and the double layer is introduced into each extruder, such as surface layer-1 / surface-2 / middle layer / double layer-2 / double layer-1 It can be produced by coextrusion molding so as to be laminated.

An antistatic agent may be further added to the resin composition constituting the surface layer as necessary. The same goes for the second floor.

Each of the above-mentioned resins for each layer is supplied to a screw type extruder in this order, extruded in a film form from a multi-layer T die at 180 to 240 ° C, and cooled while passing it through a cooling roll of 30 to 70 ° C to be substantially lead-free. It is taken as a god. Alternatively, the resin for each layer can be obtained once as a pellet, and then extruded as described above.

When drawing, it is made substantially non-stretching in order to effectively expand the film performed after dicing. This substantially non-stretching includes non-stretching or slight stretching to a degree that does not adversely affect the expansion of the dicing film. Normally, it is sufficient that the film is stretched to a degree that sagging does not occur when the film is taken.

(3) Preparation of dicing film

The dicing film of the present invention can be produced according to well-known techniques. For example, a film composed of a gas film / adhesive layer can be obtained by dissolving the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer in a solvent such as an organic solvent, applying it on a gas film for dicing, and removing the solvent.

A die-bonding film is produced by dissolving the resin composition constituting the die-bonding layer in a solvent such as an organic solvent, coating it on another film (peel film), and removing the solvent.

Further, a dicing film is produced by wrapping the pressure-sensitive adhesive layer and the die-bonding layer so as to face each other. Thereby, a film composed of a base film / adhesive layer / die bond layer can be obtained. At this stage, the die bond layer is bonded to the semiconductor wafer and the adhesive layer in a weak (pseudo) state.

After the expansion, the segmented semiconductor chip and the die-bond layer are stacked by stacking a predetermined package or semiconductor chip, and heated to a temperature at which the die-bond layer strongly adheres, and then bonded.

Example

Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.

(1) Raw material for gas film for dicing

Table 1 shows the raw materials for the gas film for dicing.

Table 1 MFR
[g / 10 min] density
[g / cm ³ ] Remark PE-1 9.0 (190˚C) 0.93 EVA, VA content 10wt% PE-2 5.0 (190˚C) 0.92 LDPE PE-3 5.3 (190˚C) 0.93 LDPE PE-4 30 (190˚C) 0.96 EVA, VA content 33wt% PE-5 18 (190˚C) 0.95 EVA, VA content 28wt% PE-6 20 (190˚C) 0.94 EVA, VA content 20wt% PE-7 15 (190˚C) 0.94 EVA, VA content 19wt% PE-8 14 (190˚C) 0.94 EVA, VA content 15wt% PE-9 3 (190˚C) 0.93 EMAA, MAA content 9wt% SEBS 4.5 (230˚C) 0.89 SEBS, St content 12wt%,
More than 95% of winning rate TPU - 1.2 Polyurethane Amorphous PO 9.2 (230˚C) 0.88 Copolymer of propylene and butene-1

[Explanation of abbreviations]

PE-1 ~ 9: Polyethylene resin 1 ~ 9

SEBS: styrene-butadiene copolymer hydrogenated

(Styrene-ethylene-butylene-styrene copolymer)

TPU: Thermoplastic polyurethane (PU)

Amorphous PO: Amorphous polyolefin

LDPE: branched low density polyethylene

EVA: ethylene-vinyl acetate copolymer

VA content: vinyl acetate content

EMAA: ethylene-methacrylic acid copolymer

MAA content: Methacrylic acid content

St content: Styrene content ratio

(Content of vinyl aromatic hydrocarbon (St) component in vinyl aromatic hydrocarbon-based resin)

(2) Preparation of base film / intermediate layer / bilayer gas film for dicing

The resin composition was blended with each component and composition so as to be the surface layer / intermediate layer / bilayer (three layers) described in Table 2, to prepare a gas film for dicing.

The resin composition constituting each layer was introduced into each extruder adjusted to 220 ° C, and then extruded by a T-die of 220 ° C, laminated, and cooled to 30 ° C so as to be in the order of the surface layer / intermediate layer / bilayer. It coextruded on the chill roll which circulates to obtain a flat three-layer film.

Table 2 Example 1 Example 2 Example 3 Example 4 Surface layer PE-1 100 100 100 100 Layer thickness (μm) 30 30 30 30 Middle floor TPU 100 75 50 25 PE-9 - 25 50 75 Layer thickness (μm) 30 30 30 30 Upstairs PE-1 100 100 100 100 Layer thickness (μm) 30 30 30 30 Overall thickness (μm) 90 90 90 90

(3) Preparation of base film for dicing of surface layer-1 / surface-2 / intermediate layer / double layer-2 / double layer-1

Resin compositions were blended with each component and composition to prepare a surface layer-1 / surface-2 / intermediate layer / two layers-2 / two layers-1 (five layers) described in Tables 3 and 4, thereby producing a gas film for dicing.

The resin composition constituting each layer was introduced into each extruder adjusted to 220 ° C, and then placed in a T die of 220 ° C in order of surface layer-1 / surface-2 / intermediate layer / double layer-2 / double layer-1. It was extruded, laminated, and coextruded onto a chill roll with 30 ° C cooling water circulating to obtain a flat 5-layer film.

Table 3 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Pave-1 PE-1 100 - 100 100 100 100 - - PE-2 - 100 - - - - 100 - PE-3 - - - - - - - 100 Layer thickness (μm) 25 25 20 20 20 20 20 20 Pave-2 PE-4 100 100 - - - - - - PE-5 - - 100 - - - 100 100 PE-6 - - - 100 - - - - PE-7 - - - - 100 - - - PE-8 - - - - - 100 - - Layer thickness (μm) 5 5 10 10 10 10 10 10 Middle floor TPU 75 75 75 75 75 75 75 75 PE-9 25 25 25 25 25 25 25 25 Layer thickness (μm) 30 30 30 30 30 30 30 30 Upstairs-2 PE-4 100 100 - - - - - - PE-5 - - 100 - - - 100 100 PE-6 - - - 100 - - - - PE-7 - - - - 100 - - - PE-8 - - - - - 100 - - Layer thickness (μm) 5 5 10 10 10 10 10 10 Upstairs-1 PE-1 100 - 100 100 100 100 - - PE-2 - 100 - - - - 100 - PE-3 - - - - - - - 100 Layer thickness (μm) 25 25 20 20 20 20 20 20 Overall thickness (μm) 90 90 90 90 90 90 90 90

Table 4 Comparative example Pave-1 PE-2 100 Layer thickness (μm) 20 Pave-2 SEBS 100 Layer thickness (μm) 10 Middle floor Amorphous PO 100 Layer thickness (μm) 30 Upstairs-2 SEBS 100 Layer thickness (μm) 10 Upstairs-1 PE-2 100 Layer thickness (μm) 20 Overall thickness (μm) 90

(4) Evaluation of gas film for dicing

(4-1) Low temperature expandability (low temperature Ex property)

<Evaluation method>

(Measurement of tensile elongation)

A film sample processed so that the distance between the chucks is 40 mm at a tensile speed of 200 mm / min and a width of 10 mm with respect to the MD direction of the film (the extrusion direction of film forming) and the TD direction (the width direction of the film formed by film forming). The tensile elongation of the film was measured using.

(Measurement of 25% modulus)

A film sample processed so that the distance between the chucks is 40 mm at a tensile speed of 200 mm / min and a width of 10 mm with respect to the MD direction of the film (the extrusion direction of film forming) and the TD direction (the width direction of the film formed by film forming). Using, SS curve (stress-strain curve) was obtained.

The stress values at 25% elongation of the obtained SS curve were read, respectively.

<Evaluation criteria>

(A) Low-temperature expandability (low-temperature ex-forming)

○: When the tensile test was performed, the elongation was 100% or more.

X: When the tensile test was performed, the film elongation was less than 100%.

(B) Uniform expandability (uniformity Ex)

The ratio of the stress value at 25% elongation in the MD direction and the stress value at 25% elongation in the TD direction was determined to obtain a modulus ratio (MD / TD).

○: Modulus ratio (MD / TD) is less than 1.5.

X: The modulus ratio (MD / TD) is 1.5 or more.

When the modulus ratio (MD / TD) is in the above range, the gas film for dicing exhibits good uniform expandability (uniformity Ex) under low temperature conditions of -15 to 5 ° C.

(4-2) Low-temperature high-speed expandability (low-temperature high-speed expandability)

<Evaluation method>

(Measurement of elongation at break (maximum elongation) (%))

Tensile Test: Using a "HYDROSHOT · HITS-T10" manufactured by SHIMADZU CORPORATION, a film sample processed at a tensile speed of 250mm / sec under a -15 ± 2˚C environment and 25mm wide to make the distance between chucks to 10mm, MD In the direction and TD direction, it was stretched until fracture.

From the data plot of load and stretch, an SS curve (stress-strain curve) was created to calculate the elongation at break (maximum elongation).

<Evaluation criteria>

(High-speed tensile test evaluation (mechanical properties))

○: The tensile elongation at break in the MD and TD directions is 120% or more.

X: The tensile elongation at break in the MD and TD directions is less than 120%.

In this evaluation method, by setting the tensile speed to 250 mm / sec and performing a tensile test, in addition to low temperature conditions, expandability under high speed conditions is evaluated. And, when the tensile elongation at break in the MD and TD directions of the film is 120% or more, for example, after stealth dicing, when the film is expanded under low-temperature conditions (-15 to 5 ° C) and high-speed conditions, the film is satisfactory. To be elongated.

(4-3) Heat Shrinkability (HS)

Condition 1-Tensile test: processed by SHIMADZU CORPORATION "autograph AG-500NX TRAPEZIUM X", under a -15 ± 2˚C environment, at a tensile speed of 200mm / min, with a width of 10mm and a chuck distance of 40mm. The film samples were stretched 200% in the MD direction and the TD direction, respectively.

Condition 2-Shrinkage test: The sample was heated for 5 seconds at a set temperature of 80 ° C using a "hygrostat TBP105DA" manufactured by MITSUBISHI HEAVY INDUSTRIES AIR-CONDITIONING AND REFRIGERATION, LTD.

<Evaluation method>

Samples of film shorts of 100 mm in length (40 mm mark spacing + grip margin (up and down 30 mm increments)) and 10 mm in width were prepared and stretched under the above condition 1.

After holding at 200% elongation for 10 seconds, the chuck was returned to its original position, the chuck was opened, and the sample was contracted under condition 2 above.

The interval L [mm] after the contraction was measured, and the recovery rate was calculated by the following calculation formula.

Recovery rate [%] = {(120-L) / 80} Х100

The recovery rate was measured in both the MD direction and the TD direction, and this was shown as heat shrinkability (HS property).

<Evaluation criteria>

(A) Heat Shrinkability (HS)

○: The recovery rate is 70% or more due to the heat shrink.

The recovery rate is more preferably 90 to 110%.

X: The recovery rate is less than 70% due to the heat shrink.

When the recovery rates in the MD and TD directions are in the above range, the gas film for dicing exhibits good heat shrinkability (HS property) in an 80 ° C environment.

(B) Uniform heat shrinkability (uniform HS property)

○: The ratio (MD / TD) of the recovery rate in the MD direction and the recovery rate in the TD direction is less than 1.2.

The recovery ratio (MD / TD) is more preferably 0.9 to 1.15.

X: The ratio of recovery rate (MD / TD) is 1.2 or more.

When the ratio (MD / TD) of the recovery rate is in the above range, the gas film for dicing exhibits good uniform heat shrinkability (uniform HS property) under the condition of 80 ° C.

Table 5 (3rd floor) Example 1 Example 2 Example 3 Example 4 Low temperature Ex ○ ○ ○ ○ Uniform Ex property ○ 0.91 ○ 1.01 ○ 1.00 ○ 1.04 Low temperature, high speed Ex property
Elongation at break (%) MD ○ 757 ○ 693 ○ 629 ○ 565 TD ○ 1026 ○ 715 ○ 404 ○ 200 HS Castle MD ○ 98 ○ 99 ○ 97 ○ 96 TD ○ 99 ○ 98 ○ 97 ○ 96 Uniform HS ○ 1.00 ○ 1.00 ○ 1.00 ○ 1.00

Table 6 (5th floor) Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Low temperature Ex ○ ○ ○ ○ ○ ○ ○ ○ Uniform Ex property ○ 1.05 ○ 1.03 ○ 1.07 ○ 0.97 ○ 1.01 ○ 0.99 ○ 0.99 ○ 1.01 Low temperature, high speed Ex property
Elongation at break (%) MD ○ 693 ○ 681 ○ 688 ○ 683 ○ 681 ○ 680 ○ 675 ○ 650 TD ○ 715 ○ 247 ○ 710 ○ 705 ○ 703 ○ 702 ○ 240 ○ 220 HS Castle MD ○ 99 ○ 94 ○ 99 ○ 99 ○ 99 ○ 99 ○ 92 ○ 85 TD ○ 98 ○ 94 ○ 98 ○ 98 ○ 98 ○ 98 ○ 90 ○ 81 Uniform HS ○ 1.00 ○ 1.00 ○ 1.00 ○ 1.00 ○ 1.00 ○ 1.00 ○ 1.02 ○ 1.05

The dicing film was uniformly stretched even when the base film for dicing of the present invention (Examples 1 to 12) was expanded under low temperature conditions.

Table 7 Comparative example Low temperature Ex ○ Uniform Ex property ○ 1.04 Low temperature, high speed Ex property
Elongation at break (%) MD × 22 TD × 48 HS Castle MD ○ 80 TD ○ 77 Uniform HS ○ 1.04

In the gas film for dicing of the present invention (example), the heat shrinkage (HS property) value was significantly higher than that of the comparative example. That is, the heat-shrinkability of the gas film for dicing of this invention was more favorable.

The low temperature expandability (low temperature Ex property) was within the allowable range in the gas film for dicing of the present invention (Example) and the comparative example.

The gas film for dicing of the present invention (Example) had better low-temperature high-speed expandability (low-temperature high-speed Ex property) than the comparative example.

(5) Discussion

Heat Shrink Castle

When the base film for dicing of the present invention is used, the dicing film (sheet) can be shrunk by shrinking its portion by heating the generated sagging portion even after the expansion process.

When using the gas film for dicing of this invention, especially the dicing film (sheet) has a high recovery rate by heat shrinkage.

When the gas film for dicing of the present invention is used, recovery of the used dicing film to the rack can be performed more quickly and easily. In other words, the gas film for dicing of the present invention has high recoverability due to heat, and furthermore, the dicing film is uniformly recovered. That is, heat shrinkability is exhibited satisfactorily and rack recovery is excellent. In addition, the products using the gas film for dicing of the present invention do not collide, so that no defect occurs.

Expandability

When the base film for dicing of the present invention is used, even when the expansion is performed under low temperature conditions, the expandability is good, and the dicing film is uniformly stretched. When the base film for dicing of the present invention is used, in an expansion performed under low temperature conditions, the semiconductor wafer and the die bond layer are cut (segmented) in a good manner.

When the base film for dicing of the present invention is used, even when the semiconductor wafer and the die bond layer are cut (divided) after stealth dicing, the expandability is obtained even when the expansion is performed under low temperature and high speed conditions. It is good, and the dicing film stretches favorably. When the gas film for dicing of the present invention is used, the semiconductor wafer and the die-bond layer are cut (segmented) satisfactorily collectively in an expansion performed under low temperature conditions and high speed conditions.

When the gas film for dicing of the present invention is used, miniaturization of semiconductor products progresses, and a sheet having a higher expandability and shrinkability is required, while the sheet needs to be further expanded (expandability).

Claims (5)

A gas film for dicing comprising a layered structure in the order of surface layer / intermediate layer / bilayer,
The surface layer and the two layers are made of a resin composition containing a polyethylene-based resin,
The intermediate layer is made of a resin composition containing a polyurethane-based resin,
Gas film for dicing. According to claim 1,
A gas film for dicing, wherein the surface layer and / or the two layers are single layers or multiple layers. The method according to claim 1 or 2,
The polyethylene-based resin, branched chain low density polyethylene (LDPE), straight chain low density polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer , Ethylene-butyl acrylate copolymer, ethylene-methyl methacrylate copolymer (EMMA), ethylene-methacrylic acid copolymer (EMAA), and at least one resin selected from the group consisting of ionomer resin, die Singong film. The method according to any one of claims 1 to 3,
A gas film for dicing, wherein the polyurethane-based resin is a thermoplastic polyurethane resin (TPU). The dicing film which provided the adhesive layer and the die bond layer in this order on the surface layer side of the base film for dicing in any one of Claims 1-4.