KR20190138457A - Anti- electrostatic discharge die attach film, Manufacturing method thereof and Process of dicing wafer - Google Patents

Abstract

The present invention relates to an anti-static die attach film and, more specifically, to a die attach film, which prevents device destruction due to charging of an electric charge during semiconductor packaging due to low delamination voltage to reduce the defective rate, and can easily bond and debond under certain conditions, thereby increasing wafer dicing and semiconductor chip pick-up process efficiency.

Description

Antistatic die attach film, manufacturing method thereof and wafer dicing process using the same {Anti-electrostatic discharge die attach film, Manufacturing method, etc.

The present invention is a die attach film (DAF) used in a wafer dicing process such as DBG (dicing before grinding) or stealth dicing before grinding (SDBG), and has an antistatic function, but bonding and debonding under specific conditions (de-bonding) relates to an easy DAF, a wafer dicing process using the same.

Generally, a wafer dicing process is a process located between a pre-spindle process called a wafer fabrication process and a post process process called an assembly process in a semiconductor manufacturing process. A wafer on which a plurality of semiconductor chips or dies are formed Refers to the process of cutting the die into individual dies.

A typical wafer dicing process involves cutting along a scribe line between dies formed on a wafer using blades that rotate at high speed or using lasers with specific energies.

The conventional blade method of sawing thin wafers of 200 μm or less into individual dies results in excessive edge cracking, chipping, and cross-sectional cracking, resulting in the fracture strength of the die. strength), i.e. the strength of the die to break. As a result, the die is easily broken even by a small external impact. The edge crack of the wafer due to the use of the blade is caused by vibration, frictional heat, etc. generated when the wafer and the blade are in mechanical contact.

In order to increase the fracture strength of the die, it is necessary to minimize the damage of the cutting surface. For this purpose, a method of thinning the blade or reducing the cutting speed has been proposed. However, the reduction of the blade thickness is limited, and the reduction of the cutting speed has the disadvantage of lowering the productivity.

On the other hand, DBG (dicing before grinding), that is, a method of applying a relatively small impact to the wafer by dicing by the blade before the back grinding (back grinding) of the wafer has been proposed, but currently being applied generally There is a constraint that it is difficult to apply a die attach film (DAF) process, and also has a problem that the die is difficult to maintain the correct position in the ring mount after backside polishing. Here, the ring mount is a device for supporting a diced wafer in general, and is a semiconductor device composed of a ring of round stainless steel whose inner lower surface is covered with tape.

Stealth dicing before grinding (SDBG), which is one of laser dicing methods, is in the spotlight due to its relatively high productivity and low damage to the cut surface. The SDBG wafer dicing method differs in cutting principle according to the type of light source.

By the way, during the packaging of DAF in the DBG or SDBG wafer dicing process, when the film is laminated, the transfer of charges in the DAF film occurs by contact with the wafer or the semiconductor chip, resulting in an electrical double layer (+ layer and-layer). When the semiconductor chip is picked up, the DAF is peeled off, and a peeling charge is generated. As a result, electrostatic current discharge occurs in an adjacent semiconductor chip during stacking of the semiconductor chip, resulting in device destruction.

Korean Laid-Open Patent No. 10-2013-0037638 (Published Date 2013.04.16) Korean Laid-Open Patent No. 10-2017-0088285 (Published Date 2017.08.01)

Disclosure of Invention An object of the present invention is to use a die attach film (DAF) provided with an antistatic function for a DAF film used in a wafer dicing process such as DBG or SDBG, thereby allowing semiconductors to be discharged by electrostatic current discharge during stacking. It is to provide a novel DAF that can prevent chip destruction of the chip.

In order to solve the above problems, the antistatic die attach film (DAF) of the present invention comprises a dicing film comprising an antistatic layer, a polyolefin film (PO film, Polyolefin film) layer, a pressure sensitive adhesive (PSA) layer; And an adhesive layer laminated on the PSA layer of the dicing film.

In one preferred embodiment of the present invention, the dicing film may be an antistatic layer, a polyolefin film layer and a PSA layer are sequentially stacked, or a polyolefin film layer, an antistatic layer and a PSA layer may be sequentially stacked.

As a preferred embodiment of the present invention, the antistatic layer may include at least one selected from Al, Al ₂ O ₃ , ITO (Indium Tin Oxide), Ni (nickel) and Ag (silver).

As a preferred embodiment of the present invention, the adhesive layer may include an adhesive in a B-stage state or an adhesive film in a B-stage state.

In one preferred embodiment of the present invention, the adhesive of the B-stage state is 60 to 75% by weight of a thermoplastic resin having a number average molecular weight of 600,000 to 1,000,000, 10 to 25% by weight of the epoxy resin, 2 to 10% by weight of the curing agent, inorganic filler 4 to 15% by weight, 0.1 to 2% by weight of the curing accelerator and 0.1 to 4% by weight of the coupling agent.

In a preferred embodiment of the present invention, the antistatic die attach film may have an electrostatic discharge (ESD) of 0.1 kV to 0.8 kV when the thickness of the antistatic layer is 5 to 30 nm.

As a preferred embodiment of the present invention, the surface resistance of the antistatic layer may be 1ⅹ10 ² ~ 1ⅹ10 ¹² ohm / sq.

As a preferred embodiment of the present invention, the storage modulus of the adhesive layer may satisfy the following equation 6.

[Equation 6]

20 ≤ value of storage modulus before curing at 25 ° C. of adhesive layer (Mpa) / value of storage modulus before curing at 130 ° C. of adhesive layer ≤ 90

In Equation 1, the storage modulus value is 20mmⅹ5mm (horizontal length) of the specimen, using a dynamic thermomechanical analyzer (Perkin Elmer, Diamond DMA), measuring temperature -30 ℃ ~ 300 ℃ (heating rate 10 ° C / min) and the measurement frequency of 10 Hz.

As a preferred embodiment of the present invention, the adhesive layer may have a storage modulus value of 3 MPa or more after curing at 260 ° C.

In one preferred embodiment of the present invention, when the adhesive layer has a thickness of 20㎛, the shear adhesive strength at 260 ℃ after curing may be 4 ~ 10 MPa.

As a preferred embodiment of the present invention, the PSA layer of the dicing film is the adhesive force at 22 ℃ to the adhesive layer is 80 ~ 300 N / m before UV (ultraviolet) curing, the adhesive strength at 22 ℃ after UV curing It may be 20 N / m or less.

As a preferred embodiment of the present invention, the adhesive force between the PSA layer and the adhesive layer has a maximum adhesive strength at a temperature of −15 ° C. to −7 ° C., and the maximum adhesive force may be 300 to 700 N / m.

As a preferred embodiment of the present invention, the adhesive force between the PSA layer and the adhesive layer of the dicing film satisfies the following Equation 1 to Equation 5 before the UV curing, the adhesive force at -13 ℃ ~ -15 ℃ -7 It may be characterized by being higher than the adhesive force at ℃ ~ -10 ℃.

Equation 1

Adhesion at 150 N / m ≤ 0 ° C ≤ 470 N / m

 [Equation 2]

Adhesion at 220 N / m ≤ -3 ° C to -5 ° C ≤ 520 N / m

[Equation 3]

Adhesion at 300 N / m ≤ -7 ° C to -10 ° C ≤ 540 N / m

[Equation 4]

305 N / m ≤ -13 ° C -15 ° C adhesive force ≤ 700 N / m

[Equation 5]

Adhesion at -18 ° C to -20 ° C ≤ 500 N / m

As a preferred embodiment of the present invention, the PSA layer may be formed of a PSA resin containing 90 to 97% by weight of the acrylic copolymer resin, 2 to 8% by weight of the thermosetting agent and 0.1 to 2% by weight of the photoinitiator.

In a preferred embodiment of the present invention, the acrylic copolymer resin is 10 to 40 parts by weight of 2-hydroxyethyl acrylate, 10 to 40 parts by weight of 2-methacryloyloxyethyl isocyanate based on 100 parts by weight of 2-ethylhexyl acrylate. It may include a copolymer copolymerized with 45 parts by weight.

In one preferred embodiment of the present invention, the copolymer may be a copolymer further copolymerized with at least one selected from ethylhexyl methacrylate and hydroxylethyl methacrylate.

As a preferred embodiment of the present invention, the ethyl hexyl methacrylate may be used at 5 to 135 parts by weight based on 100 parts by weight of 2-ethylhexyl acrylate.

As a preferred embodiment of the present invention, the hydroxyl ethyl methacrylate may be used in 3 to 30 parts by weight based on 100 parts by weight of 2-ethylhexyl acrylate.

In one preferred embodiment of the present invention, the adhesive force between the adhesive layer and the PSA layer has a maximum adhesive strength at a temperature of -20 ℃ ~ -7 ℃, the maximum adhesive strength may be 300 ~ 700 N / m.

As a preferred embodiment of the present invention, in the die attach film of the present invention, the adhesive layer may have an average thickness of 5 μm to 60 μm, and the dicing film layer may be 60 μm to 150 μm.

As a preferred embodiment of the present invention, the PSA layer is 5㎛ ~ 30㎛, the antistatic layer may be an average thickness of 1 nm ~ 30nm.

As a preferred embodiment of the present invention, when the die attach film of the present invention is viewed from the upper direction of the adhesive layer, the adhesive layer is present inside the PSA layer, and the area of the adhesive layer may be smaller than the area of the PSA layer. .

As a preferred embodiment of the present invention, the die attach film of the present invention may be further laminated on the protective film layer (or release film layer) on the adhesive layer.

Another object of the present invention relates to a method for manufacturing a die attach film described above, comprising: a step of manufacturing a dicing film including an antistatic layer, a polyolefin film layer, and a PSA layer; And forming an adhesive layer by laminating an adhesive film on the PSA layer of the dicing film, or casting and drying an adhesive on the PSA layer of the dicing film, to form an adhesive layer. can do.

In one preferred embodiment of the present invention, the dicing film may be an antistatic layer, a polyolefin film layer and a PSA layer are sequentially stacked, or a polyolefin film layer, an antistatic layer and a PSA layer may be sequentially stacked.

In a preferred embodiment of the present invention, the adhesive film or adhesive layer may be in a B-stage state.

Another object of the present invention is to provide a dicing before grinding (DBG) or stealth dicing before grinding (SDBG) wafer dicing process using the die attach film described above.

The die attach film of the present invention has a low peeling electrification voltage, which prevents device destruction due to charge charging during semiconductor packaging, thereby greatly lowering the defect rate, and before the UV curing, the adhesive layer in the film maintains high adhesion between the PSA layers. After UV curing, the adhesive layer in the film has a very low adhesive strength with the PSA layer, which enables effective bonding and debonding, thereby increasing wafer dicing and semiconductor chip pick-up process efficiency.

1 to 3 are each a schematic diagram of an antistatic DAF of the present invention as a preferred embodiment of the present invention.
Figure 4 shows a schematic diagram of the adhesive layer of the DAF of the present invention is picked up with the wafer by stacking the chip with a weak adhesive force with the PSA through UV curing after laminating the wafer before UV curing.

The term "B-stage state" in the term used in the present invention refers to a semi-cured state, and specifically refers to an intermediate state during the curing reaction process of the material. In addition, the "C-stage state" refers to a fully cured state.

Hereinafter, the present invention will be described in more detail.

In the DBG (dicing before grinding) or SDBG wafer dicing process, the DAF is adhered to the back side of the polished wafer, the background tape adhered to the opposite side of the polished back side of the wafer is peeled off, and then the DAF is expanded ( expanding) and then performing a UV irradiation process. Thereafter, a semiconductor chip is manufactured by sequentially performing a semiconductor chip pick-up process, a semiconductor chip stack process, a wire bonding process, and an EMC molding process.

However, when the DAF is bonded, an electric double layer (+ layer and-layer) is formed by contact with the semiconductor by contact with the semiconductor. During the semiconductor chip pick-up process, the adhesive layer in the DAF film includes a dicing film layer (including the PSA layer) and When the separation, the peeling charge will occur. In addition, since the DAF film performs an expanding process and the like, it is necessary to maintain an appropriate adhesive force before the UV irradiation process, and after UV irradiation, the adhesive force must be low to facilitate separation for smooth semiconductor chip pickup.

The present invention relates to an antistatic die attach film (hereinafter referred to as DAF) that satisfies such conditions.

1 to 2, the DAF of the present invention includes an antistatic layer (4, 4 '), a polyolefin film (PO film, Polyolefin film) layer (3), PSA (Pressure sensitive adhesive) layer (2) Dicing films (10, 10 ') comprising a; And an adhesive layer 1 stacked on the PSA layer 2 of the dicing film.

In the dicing film of the DAF of the present invention, the antistatic layer 4, the polyolefin film layer 3, and the PSA layer 2 may be stacked in this order as in the schematic diagram of FIG. 1.

Moreover, in the dicing film of DAF of this invention, the polyolefin film layer 3, the antistatic layer 4 ', and the PSA layer 2 may be laminated one by one like the schematic of FIG.

When the DAF of the present invention is viewed from the upper direction of the adhesive layer 1, the adhesive layer 1 is present inside the PSA layer 2, and the area of the adhesive layer may be smaller than the area of the PSA layer.

In addition, the DAF of the present invention may be further laminated with a protective film layer (or release film layer) 30, 30 'on the adhesive layer (1), it is formed in various forms, such as A ~ C of FIG. It may be.

Hereinafter, the dicing film and adhesive bond layer which comprise DAF of this invention are demonstrated concretely.

The polyolefin film layer constituting the dicing film serves as a substrate, and low density polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymerized polypropylene, polyolefin copolymer of block copolymerized polypropylene and ethylene-vinyl acetate airborne Single or two or more polyolefin resins selected from copolymers, ionomer resins, ethylene- (meth) acrylic acid copolymers and ethylene- (meth) acrylic acid copolymers are preferably low density polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene. And a single or two or more polyolefin resins selected from random copolymerized polypropylene can be used, and can be formed in a single layer or multiple layers.

Next, the antistatic layer constituting the dicing film is to lower the peeling voltage of the DAF to prevent the destruction of the device due to charge charging during semiconductor packaging, the average thickness is 1 nm ~ 35nm, preferably It is good that it is 2-30 nm, More preferably, it is 2-25 nm. At this time, the average thickness of the antistatic layer to form less than 1 nm is technically limited, there may be a problem that the peeling voltage is increased to 1 kV or more, if the average thickness of the antistatic layer exceeds 35 nm UV transmittance There may be a problem that it is difficult to UV cure the PSA layer by lowering it below 5%.

The antistatic layer may be formed of one or two or more selected from Al, Al ₂ O ₃ , indium tin oxide (ITO), Ni, and Ag.

[ PSA layer ]

Next, the PSA layer constituting the dicing film maintains high adhesive strength with the adhesive layer before the adhesive layer is UV cured, but after the UV adhesive has been cured, the adhesive force becomes very weak and easy to peel off from the adhesive layer. The PSA layer is formed by directly casting coating and drying the PSA resin on one surface of the polyolefin film or the antistatic layer, or separately preparing a PSA film using the PSA resin, and then laminating the polyolefin film or the antistatic layer on one surface. It is also possible to form a PSA layer.

In the DAF of the present invention, the average thickness of the PSA layer is preferably 5 μm to 30 μm. In this case, when the thickness of the PSA layer is less than 5 μm, the adhesive force may not be sufficient so that the dicing film is detached from the ring frame during the wafer expansion process. There may be a problem, if it exceeds 30㎛ may remain a problem that causes a residual solvent remaining in the drying after the film cast causing the adhesive solidification with the adhesive film.

PSA resin used to form the PSA layer includes an acrylic copolymer resin, a thermosetting agent and a photoinitiator.

The acrylic copolymer resin is a copolymer obtained by copolymerizing 10 to 40 parts by weight of 2-hydroxyethyl acrylate and 10 to 45 parts by weight of 2-methacryloyloxyethyl isocyanate with respect to 100 parts by weight of 2-ethylhexyl acrylate. It is preferable to include, and preferably copolymerized with 15 to 38 parts by weight of 2-hydroxyethyl acrylate and 20 to 40 parts by weight of 2-methacryloyloxyethyl isocyanate based on 100 parts by weight of 2-ethylhexyl acrylate. More preferably, the copolymer is copolymerized with 15 to 35 parts by weight of 2-hydroxyethyl acrylate and 25 to 38.5 parts by weight of 2-methacryloyloxyethyl isocyanate based on 100 parts by weight of 2-ethylhexyl acrylate. Copolymers may be included.

At this time, when the amount of 2-hydroxyethyl acrylate is less than 10 parts by weight, there may be a problem in that the adhesion of the PSA layer at 0 ° C. or less is very low. Branches can be problematic. And, if less than 10 parts by weight of methacryloyloxyethyl isocyanate may have a problem of having a maximum adhesive strength at -3 ~ -5 ℃ degree, if more than 45 parts by weight after the UV curing of PSA too low adhesive ring in the pickup process There may be a problem of frame detachment or chip scattering.

The acrylic copolymer resin may include one or two selected from ethylhexyl methacrylate and hydroxylethyl methacrylate in addition to 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methacryloyloxyethyl isocyanate. It may be a copolymer further copolymerized.

More specifically, the acrylic copolymer resin may further copolymerize 5 to 135 parts by weight of ethylhexyl methacrylate with respect to 100 parts by weight of 2-ethylhexyl acrylate, or preferably 5 to 75 parts by weight of ethylhexyl methacrylate. More preferably, 6 to 45 parts by weight of ethylhexyl methacrylate may be further copolymerized.

In addition, the acrylic copolymer resin is 3 to 30 parts by weight of hydroxylethyl methacrylate, preferably 4 to 20 parts by weight of hydroxylethyl methacrylate, more preferably hydroxy to 100 parts by weight of 2-ethylhexyl acrylate. It can be prepared by further copolymerizing 5 to 10 parts by weight of the hydroxylethyl methacrylate.

In addition, the acrylic copolymer resin is 90 to 97% by weight, preferably 91 to 96.5% by weight, more preferably 92 to 96% by weight of the total weight of the PSA resin. In this case, when the acrylic copolymer resin content is less than 90% by weight, there may be a problem that low-temperature adhesive strength before UV curing between the PSA layer and the adhesive layer is low, and when the content exceeds 97% by weight, the other components are too small to reduce the overall adhesiveness. There may be a problem.

In addition, the PSA resin may include 2 to 8% by weight, preferably 3 to 7% by weight of the thermosetting agent, when the content of the thermosetting agent is less than 2% by weight of the PSA layer lacks the cohesion of the ring frame or There may be a problem that the transition to the adhesive film layer, if more than 8% by weight may have a problem that the adhesive force before UV is too low to detach from the ring frame. As the thermosetting agent, a general thermosetting agent used in the art may be used, and preferably at least one selected from polyisocyanate, more preferably toluene diisocyanate, diphenylmethane diisocyanate, and nuxa methylene diisocyanate. Polyisocyanate containing can be used

In addition, the PSA resin may comprise 0.1 to 2% by weight of the photoinitiator, preferably 0.4 to 1.5% by weight, more preferably 0.5 to 1.2% by weight of the photoinitiator. As the photoinitiator, general photoinitiators used in the art may be used, and preferably, as photoinitiators, benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin iso Butyl ether, benzoin benzoic acid, benzoin benzoic acid methyl, benzoin dimethyl ketal, 2,4-diethylthioxanthone, hydroxy cyclohexyl phenyl ketone, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, azo bisisobuty One or two or more selected from ronitrile, benzyl, dibenzyl, diacetyl and β-chloroanthraquinone may be used in combination.

The dicing film including the antistatic layer, the polyolefin film layer, and the PSA layer described above may have an average thickness of 60 μm to 150 μm, preferably 80 μm to 130 μm, and the average thickness of the dicing film is 60 μm. If the thickness of the wafer is less than one, there may be a problem in that the film is torn during wafer expansion or the force transmission is not smooth, and the wafer may not be segmented.If the average thickness exceeds 150 µm, too much force is transferred to the wafer when the film is expanded so that the chip may be broken. There may be a problem with scattering.

[ Adhesive layer ]

Next, the adhesive layer is formed by casting and drying an adhesive resin (or adhesive) on one surface of the PSA layer or by preparing an adhesive film using the adhesive resin, and then laminating the adhesive film on one surface of the PSA layer to die It can be integrated with a sing film.

The adhesive layer of the present invention is present in the B-stage state, and after lamination with the wafer, when PSA adhesion is weakened through UV curing, the adhesive layer is picked up together with the wafer to stack the chips (see FIG. 4).

The adhesive resin (or adhesive) used to form the adhesive layer may be a thermoplastic resin; Epoxy resins; Curing agent; Inorganic fillers; Curing accelerators; And a coupling agent; may be prepared by mixing a composition including the same.

The thermoplastic resin may have a number average molecular weight of 600,000 to 1,000,000, preferably a number average molecular weight of 700,000 to 900,000, more preferably 740,000 to 870,000, wherein the number average molecular weight of the thermoplastic resin is less than 600,000 This is because there may be a problem in that the reliability is lowered due to lack of heat resistance, and if the number average molecular weight exceeds 1,000,000, there may be a problem in that the initial adhesion characteristics are lowered due to excessive cohesion.

As the thermoplastic resin, an acrylic copolymer resin may be used, and preferably an acrylic copolymer resin having a glass transition temperature of 10 to 20 ° C, and more preferably a glass transition temperature of 12 to 18 ° C. The acrylic copolymer resin may be a copolymer of ethyl acrylate, butyl acrylate, methyl methacrylate, glycidyl acrylate, and acrylonitrile, wherein glycidyl acrylate is a monomer of the copolymer. And acrylonitrile may be copolymerized at a weight ratio of 6.5 to 12, and more preferably glycidyl acrylate and acrylonitrile may be copolymerized at a weight ratio of 8 to 10.

And, the content of the thermoplastic resin in the total weight of the adhesive resin is 60 to 75% by weight, preferably 62 to 74% by weight, more preferably 65 to 72% by weight, if the thermoplastic resin content is less than 60% by weight reinforcement The film may have a problem that the adhesive effect is insufficient due to the lack of elasticity before curing, and difficult to manufacture, and if the content exceeds 75% by weight, the content of the thermosetting part may be insufficient, resulting in low overall crosslinking degree, resulting in poor adhesive strength and poor heat resistance after curing. Because.

In the adhesive resin component, the epoxy resin may be used by mixing a bisphenol epoxy resin and a cresol novolac epoxy resin in a weight ratio of 1: 0.2 to 1.2, preferably in a weight ratio of 1: 0.5 to 1.2. At this time, if the amount of cresol novolac-based epoxy resin is less than 0.2 weight ratio, the crosslinking point for forming three-dimensional crosslinking may be insufficient, and heat resistance may be insufficient. If the amount of cresol novolac-based epoxy resin is more than 1.2 weight ratio, the crosslinking degree is too high and impact resistance is increased. There may be a problem. The bisphenol-based epoxy resin is a bisphenol A epoxy resin having an equivalent weight of 400 to 500 g / eq and a softening point of 57 ° C. to 70 ° C., and more preferably a bisphenol A epoxy resin having an equivalent weight of 440 to 495 g / eq and a softening point of 60 ° C. to 68 ° C. It is good to use In addition, the cresol novolac-based epoxy resin may be used cresol novolac epoxy resin having an equivalent weight of 150 ~ 250 g / eq and softening point 48 ℃ ~ 54 ℃, more preferably 180 ~ 220 g / eq and softening point 50 ℃ ~ It is preferable to use a cresol novolac epoxy resin at 54 ° C. In addition, the content of the epoxy resin in the total weight of the adhesive resin is 10 to 25% by weight, preferably 12 to 22% by weight, more preferably 15 to 20% by weight, if the epoxy resin content is less than 10% by weight reinforcement After curing of the film may have a problem of insufficient adhesive strength, if it exceeds 25% by weight, the brittleness before and after curing is strong, the effect of reducing the adhesive effect at the time of the algae, the impact resistance after curing may be a problem.

In addition, the curing agent in the adhesive resin component may be used a general one used in the art, preferably a phenol novolak resin having an OH equivalent of 95 to 120 g / eq and a softening point of 110 ℃ to 130 ℃, more preferably Preferably, phenol novolac resins having an OH equivalent of 100 to 110 g / eq and a softening point of 115 ° C to 125 ° C are preferred. In addition, the content of the curing agent in the total weight of the adhesive resin is 2 to 10% by weight, preferably 3 to 8% by weight, more preferably 4 to 7.5% by weight, if the content of the curing agent is less than 2% by weight of the reinforcing film It is because there may be a problem that the crosslinking density is too low after curing, and the adhesive strength is insufficient, and when it exceeds 10% by weight, there may be a problem that the reliability is lowered due to the remaining of the unreacted curing agent.

In addition, the inorganic filler in the adhesive resin component serves to complement the dimensional stability and heat resistance, it may be used one or more selected from silica, alumina, carbon black, titanium dioxide and barium titanate. In addition, the inorganic filler is preferably an average particle diameter of 10 to 100 nm, preferably 10 to 50 nm. In addition, the content of the inorganic filler in the total weight of the adhesive resin is 4 to 15% by weight, preferably 6 to 13% by weight, more preferably 7 to 12.5% by weight, if the inorganic filler content is less than 4% by weight thermal expansion This is because there may be a problem that the coefficient of adhesion increases due to thermal expansion and contraction, so that the inter-substrate adhesive force is lowered, and when the content exceeds 15% by weight, the adhesive force may be significantly reduced.

In addition, the curing accelerator in the adhesive resin component serves to promote curing when UV-curing the adhesive layer in the B-stage state, it is possible to use an imidazole-based curing accelerator or phosphorus curing accelerator, preferably already It is preferable to use a dazole-based curing accelerator. In this case, the imidazole curing accelerator is 2E4MZ, 2E4MZ-A, 2E4MZ-CN, 2PZ, 2PZ-CN, 2P4MZ, C11Z, C11Z-CN, C11Z-CNS, C17Z, 2MZ, 2MZ-H, 2PHZ- It may include one or more selected from S, 2PHZ-PW, 2P4MHZ-PW and TBZ. And, the phosphorus-based curing accelerator in triphenylphosphine, tributyl phosphine, tritolyl phosphine, trixyl yl phosphine, phosphine oxide, triphenyl phosphonium tetraphenyl borate, tetraphenyl phosphonium and tetraphenyl forrate It may include one or more selected. And, the content of the curing accelerator in the total weight of the adhesive resin is preferably 0.1 to 2% by weight, preferably 0.1 to 1% by weight, more preferably 0.1 to 0.8% by weight, if the content of the curing accelerator is less than 0.1% by weight This is because the product hardening time is too long, there may be a problem that the productivity is significantly lowered, if it exceeds 1% by weight there is a problem that the use period is reduced due to lack of stability over time.

In addition, the coupling agent in the adhesive resin component serves to increase the adhesion force due to the chemical bonding between the surface of the inorganic filler and the organic material, but may be used a general coupling agent used in the art, preferably a silane coupling agent Can be used. In addition, the content of the coupling agent in the total weight of the adhesive resin is 0.1 to 4% by weight, preferably 0.5 to 2.5% by weight, more preferably 0.5 to 2% by weight, if the coupling agent content is less than 0.1% by weight inorganic It may be a problem that the adhesive force is not sufficiently wrapped around the surface of the filler, and if the content exceeds 4% by weight, the content of the volatile low molecular weight is too high, which may cause a problem of lowering reliability due to the remaining coupling agent.

In the present invention, the adhesive layer has an average thickness of 3 μm to 60 μm, preferably 5 μm to 55 μm, and more preferably 10 μm to 50 μm, but the average thickness of the adhesive layer is less than 3 μm. If there is a problem that the pick-up property is inferior, if it exceeds 60㎛ not only the pick-up property is bad, but also may cause a problem that the chip is broken during the expanded dicing process.

Such an adhesive layer may have a storage modulus before UV curing satisfying Equation 1 below.

0 ≤ storage modulus value (Mpa) at 25 ° C. before UV curing of the adhesive layer / save modulus value (Mpa) at 130 ° C. before UV curing of the adhesive layer ≤ 90, preferably 18 ≤ before UV curing of the adhesive layer 25 Storage modulus value at ℃ (Mpa) / Storage modulus value at 130 ℃ before UV curing of the adhesive layer (Mpa) ≤ 80

In the above Equation 1, the storage modulus value is 20mmmm5mm (horizontal length) of the specimen using a dynamic thermomechanical analyzer (Perkin Elmer, Diamond DMA), measuring temperature -30 ℃ ~ 300 ℃ (heating rate 10 ° C / min) and the measurement frequency of 10 Hz.

In addition, the adhesive layer may have a storage modulus value of 3 MPa or more at 260 ° C. after UV curing, and may preferably be 3.2 to 11 MPa. In addition, the adhesive layer may have a storage modulus value of 140 to 300 MPa at 25 ° C. after curing, and preferably 148 to 275 MPa.

In addition, when the adhesive layer has a thickness of 20 μm, the shear adhesive strength at 260 ° C. after curing may be 4 to 10 MPa, preferably 4.5 to 9.0 MPa. In this case, the shear adhesion strength is related to the reflow resistance property of the adhesive film, and if less than 4Mpa, there may be a problem such that cracks in the adhesive film may occur due to the low reflow resistance due to the low adhesive force. If it exceeds 10 Mpa, there may be a problem that the impact resistance of the adhesive film is lowered.

In the DAF of the present invention, the adhesive force at 22 ° C between the PSA layer of the dicing film and the adhesive layer is 80 to 300 N / m, preferably 100 to 200 N / m, more preferably 120 to 180 N / m, and after UV curing, the adhesive force at 22 ° C. may be 4 to 20 N / m, preferably 4 to 15 N / m or less, and more preferably 5 to 15 N / m. At this time, if the adhesive force at 22 ° C is less than 4 N / m, the adhesive force is too low, there is a problem that the chip is broken and scattered during the expanded dicing process.

In addition, the DAF of the present invention has a maximum adhesive strength between the PSA layer and the adhesive layer is -15 ℃ ~ -10 ℃, preferably -15 ℃--13 ℃ temperature, the maximum adhesive strength is 300 ~ 700 N may be / m.

In addition, in the DAF of the present invention, the adhesive force between the PSA layer and the adhesive layer of the dicing film satisfies the following Equation 1 to Equation 5 before UV curing, but the adhesive force at -13 ° C to -15 ° C is -7 ° C to It is characterized by higher adhesion than -10 ℃.

Equation 1

Adhesion at 150 N / m ≤ 0 ° C ≤ 470 N / m, preferably at 180 N / m ≤ 0 ° C ≤ 450 N / m

 [Equation 2]

Adhesion at 220 N / m ≤ -3 ° C to -5 ° C ≤ 520 N / m, preferably at 245 N / m ≤ -3 ° C to -5 ° C ≤ 510 N / m

[Equation 3]

Adhesion at 300 N / m ≤ -7 ° C to -10 ° C ≤ 540 N / m, preferably at 305 N / m ≤ -7 ° C to -10 ° C ≤ 505 N / m

[Equation 4]

Adhesion at 305 N / m ≤ -13 ° C -15 ° C ≤ 700 N / m, preferably at 310 N / m ≤ -13 ° C -15 ° C ≤ 600 N / m

[Equation 5]

Adhesion at -18 ° C to -20 ° C ≤ 500 N / m, preferably 200 N / m ≤ Adhesion at -18 ° C to -20 ° C ≤ 450 N / m

Antistatic die attach film (DAF) of the present invention described above is a step of manufacturing a dicing film comprising an antistatic layer, a polyolefin film layer, a PSA layer; And forming an adhesive layer by laminating an adhesive film on the PSA layer of the dicing film, or casting and drying an adhesive on the PSA layer of the dicing film, to form an adhesive layer. can do.

In the dicing film of the first step, an antistatic layer, a polyolefin film layer and a PSA layer may be sequentially stacked, or a polyolefin film layer, an antistatic layer and a PSA layer may be sequentially stacked.

In addition, the adhesive film or the adhesive layer of the second step is in a B-stage state.

The present invention may perform a dicing before grinding (DBG) or stealth dicing before grinding (SDBG) wafer dicing process using the antistatic die attach film.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are not intended to limit the scope of the present invention, which will be construed as to help the understanding of the present invention.

[ Example ]

Preparation  1-1: Production of Adhesive Resin and Adhesive Film

67% by weight of an acrylic copolymer (N company, trade name: SG-P3) containing a number average molecular weight of 800,000 and a glass transition temperature of 15 ° C and 3% by weight of glycidyl acrylate as a thermoplastic resin, an equivalent of 475 g / eq and a softening point. 8 wt% of bisphenol A epoxy resin (K Chemical Company, YD-011) at 65 ° C, equivalent to 200 g / eq and 8 wt% of cresol novolac epoxy resin (K Chemical Company, YDCN 1P) at 52 ° C softening point 6 wt% of phenol novolac resin (trade name: KPH-F2004 of Kolon Oil Corporation) with an OH equivalent of 106 g / eq and a softening point of 120 ° C., 9.5 wt% of silica (Aerosil R972 of E company) having an average particle diameter of 15 to 17 nm, and curing The resin for adhesives was prepared by mixing 0.5 weight% of imidazole compounds (cuazole 2PH from Shikoku Chemicals) and 1 weight% of silane coupling agents (KBM-303 from Shin-Etsu Co., Ltd.) as accelerators.

Next, the adhesive resin was cast on a release-treated polyester film, followed by hot air drying at 140 ° C. for 5 minutes to prepare an adhesive film of B-stage having an average thickness of 20 μm.

Preparation Example 1 -2 to Preparation  1-7 and Comparative Preparation  1-1 to Comparative Preparation  1-6

To prepare an adhesive resin and an adhesive film in the same manner as in Preparation Example 1-1, but to prepare a resin having a composition and composition ratio as shown in Table 1 below, to prepare an adhesive film using each of Preparation Examples 1-2 to 1 -7 and Comparative Preparation Examples 1-1 to 1-6 were carried out, respectively.

division
(weight%) Thermoplastic resin Epoxy resin Hardener weapon
Filler Hardening
accelerant Coupling agent Acrylic copolymer Bisphenol-based Cresol novolac Phenolic Novolak Resin Silica Imidazole compounds Silane coupling agent Preparation Example 1-1 67 8 8 6 9.5 0.5 One Preparation Example 1-2 62.2 10 8 6 9.5 0.5 One Preparation Example 1-3 74 5 5 5.5 9 0.5 One Preparation Example 1-4 67 10 6 6 9.5 0.5 One Preparation Example 1-5 67 7 9 6 9.5 0.5 One Preparation Example 1-6 72 8.5 8 6 4 0.5 One Preparation Example 1-7 65 7 7 5.5 14 0.5 One Comparative Preparation Example 1-1 57 11 11 8.5 11 0.5 One Comparative Preparation Example 1-2 78 5 5 4.5 6.3 0.4 0.8 Comparative Preparation Example 1-3 67 16 - 6 9.5 0.5 One Comparative Preparation Example 1-4 67 6 10 6 9.5 0.5 One Comparative Preparation Example 1-5 71 10 9.5 6 2 0.5 One Comparative Preparation Example 1-6 64 6.5 6.5 5 16.5 0.5 One

Experimental Example  1: Measurement of physical properties of the adhesive film

The storage modulus and adhesive strength, which are physical properties of the adhesive film prepared in Preparation Example and Comparative Preparation Example, were measured by the following method, and the results are shown in Table 2 below.

(One) Storage modulus  Measure

The storage modulus was measured by using a dynamic thermomechanical analysis device (Perkin Elmer, Diamond DMA) of 50 layers of 20 mm × 5 mm × 20 μm in width (vertical thickness × thickness). Minutes), and the measurement frequency was applied based on the measurement method by applying a frequency of 10 Hz. In addition, the storage modulus of the adhesive film in the B-stage state before curing at 25 ° C and 130 ° C was measured, and the adhesive film in the C-stage state at 25 ° C and 260 ° C after curing the adhesive film of the same composition. The storage modulus was measured, and the storage modulus values in Table 2 were obtained by dividing the measured storage modulus value by the specimen thickness.

(2) Shear adhesive strength measurement

Shear adhesion strength is that the adhesive film (thickness 20㎛) is laminated with an upper substrate wafer (0.5 mm thick) at 60 ° C., and then cut into a size of 5 mm 5 mm, and a pressure of 130 ° C. and 1 kgf is applied to the lower substrate wafer 0.5 mm thick. Bonded under, curing was carried out at 180 ° C. for 2 hours. After curing was completed, the shear bond strength of the lower substrate wafer was measured under a speed of 0.5 mm / sec and 260 ° C. At this time, after curing, the shear adhesive strength at 260 ° C. must satisfy 4 to 10 Mpa to pass.

division Before hardening
Storage modulus
(Mpa) Storage modulus after curing
(Mpa) After curing
Shear bond strength
(Mpa) 25 ℃ 130 ℃ 25 ℃ /
130 ℃ ⁽¹⁾ 25 ℃ 260 ℃ 260 ℃ Preparation Example 1-1 63 1.3 48 201 6.9 5.9 Preparation Example 1-2 89 1.2 74 267 9.1 6.7 Preparation Example 1-3 58 2.8 21 179 4.3 5.1 Preparation Example 1-4 67 1.1 61 197 6.4 5.3 Preparation Example 1-5 61 1.4 44 237 8.4 6.2 Preparation Example 1-6 47 0.7 67 152 3.4 4.7 Preparation Example 1-7 88 3.0 29 249 8.1 6.6 Comparative Preparation Example 1-1 98 Not measurable
(<0.5) - 322 12.3 8.9 Comparative Preparation Example 1-2 49 3.7 13 144 2.9 1.8 Comparative Preparation Example 1-3 68 1.0 68 161 5.1 2.1 Comparative Preparation Example 1-4 142 1.4 101 332 10.9 8.8 Comparative Preparation Example 1-5 39 Not measurable
(<0.5) - 101 1.3 2.8 Comparative Preparation Example 1-6 114 5.1 22 403 12.1 2.7 (1) 25 ° C / 130 ° C means a value obtained by dividing the storage modulus value Mpa at 25 ° C of the adhesive layer before curing by the storage modulus value Mpa at 130 ° C of the adhesive layer before curing.

Looking at the measurement results of Table 2, the adhesive films of Preparation Examples 1-1 to 1-7 showed an appropriate range of storage modulus and adhesive strength before and after curing.

On the other hand, in Comparative Preparation Example 1-1 having a thermoplastic resin content of less than 60% by weight, the adhesive layer was easily broken due to insufficient elasticity before curing, which made it difficult to measure the storage modulus at 130 ° C. In the case of Comparative Preparation Example 1-2 having a thermoplastic resin content of more than 75% by weight, the total crosslinking degree was low due to insufficient content of the thermosetting portion, and the 25 ° C / 130 ° C storage modulus ratio was less than 20, and after curing, at 260 ° C. There was a problem that the storage modulus of was low, the adhesive strength was lowered and the heat resistance was insufficient.

In addition, in Comparative Preparation Examples 1-3 without using the cresol novolak-based resin in the epoxy resin, there was a problem in that heat resistance and adhesiveness were insufficient due to the lack of a crosslinking point to form three-dimensional crosslinking. In the case of Comparative Preparation Example 1-4 exceeding the 1.2 weight ratio, the overall storage modulus and adhesive strength were excellent, but the 25 ° C / 130 ° C storage modulus ratio exceeded 90, and the crosslinking degree was too high, which may be vulnerable to impact resistance. Can be.

In Comparative Preparation Example 1-5 using an inorganic filler content of less than 4% by weight, the coefficient of thermal expansion increases, and there is a problem that the adhesive strength between substrates decreases due to thermal expansion and contraction at 260 ° C after curing, and at 260 ° C. The storage modulus was too low. In Comparative Preparation Examples 1-6, in which the inorganic filler was used in an amount of more than 15% by weight, there was a problem in that the adhesion to the lower substrate wafer was insufficient and the adhesive force was significantly lowered.

Preparation  2-1: Preparation of PSA Adhesive Resin and Laminated Film

A number average molecular weight of 600,000 and 94% by weight of an acrylic copolymer resin having a glass transition temperature of -40 ° C, 5% by weight of a polyisocyanate (AK75 from Aekyung Chemical) and 1% by weight of a photoinitiator (Ciba specialty Chemical Inc, IRGACURE 184) as a thermosetting agent The mixed resin was cast on a polyester film subjected to a release treatment, and then hot-air dried at 140 ° C. for 5 minutes to obtain a PSA film having an average thickness of 10 μm. And a PSA layer was laminated | stacked at normal temperature (15-30 degreeC) on the 80 micrometer polyolefin film (made with the polyolefin resin containing EPG-80 of Philmax, medium density polyethylene, and a random copolymerized polypropylene), and produced the laminated | multilayer film.

In this case, the acrylic copolymer resin is prepared by copolymerizing 33.3 parts by weight of 2-hydroxyethyl acrylate and 33.3 parts by weight of 2-methacryloyloxyethyl isocyanate based on 100 parts by weight of 2-ethylhexyl acrylate.

Preparation  2-2 to 2-5 and Comparative Preparation  2-1 to 2-6

To prepare a laminated film in the same manner as in Preparation Example 2-1, to prepare an acrylic copolymer resin having a composition as shown in Table 3, and then to prepare a laminated film having a composition in Table 3 using this.

division Acrylic copolymer resin Thermosetting agent
(weight%) Photoinitiator
(weight%) Monomer (parts by weight) Acrylic copolymer resin
(weight%) EHA EHMA HEMA HEA MOI Preparation Example 2-1 100 0 0 33.3 33.3 94 5 One Preparation Example 2-2 100 0 0 28.6 28.6 94 5 One Preparation Example 2-3 100 125 0 25 37.5 94 5 One Preparation Example 2-4 100 7.1 7.1 28.6 28.6 94 5 One Preparation Example 2-5 100 41.7 8.33 16.7 33.3 94 5 One Preparation Example 2-6 100 0 0 33.3 33.3 92 7 One Preparation Example 2-7 100 0 0 33.3 33.3 96 3 One Comparative Preparation Example 2-1 100 0 33.3 0 33.3 94 5 One Comparative Preparation Example 2-2 100 16.7 16.7 0 33.3 94 5 One Comparative Preparation Example 2-3 100 0 0 45.0 33.3 94 5 One Comparative Preparation Example 2-4 100 0 0 33.3 48.5 94 5 One Comparative Preparation Example 2-5 100 5 0 39.2 8 94 5 One Comparative Preparation Example 2-6 100 0 0 33.3 33.3 89.5 8.5 2 EHA: 2-ethylhexyl acrylate
HEA: 2-hydroxyethyl acrylate
MOI: 2-methacryloyloxyethyl isocyanate
EHMA: ethylhexyl methacrylate
HEMA: hydroxylethyl methacrylate

Experimental Example  2 : Of PSA layer On the adhesive layer  Adhesion Measurement by Temperature

Preparation Example 1-1 in the direction of the PSA layer of the laminated film prepared in Preparation Examples 2-1 to 2-5 and Comparative Preparation Examples 2-1 to 2-6 using an adhesive film and a roll laminator of 25 ℃ 25mm A specimen was prepared by cutting to (width) x 100 mm (length). Next, roll the DAF film at 60 ° C. in the direction of the adhesive layer of the DAF film on the back side of the prepared specimen of a 500 μm thick 8 inch silicon wafer (a wafer subjected to # 2300 grinding using a DFD-840 grinding machine manufactured by Disco). The adhesive force (-20-22 degreeC) before UV hardening by the temperature of the dicing film with respect to the adhesive bond layer was measured on the measurement conditions of 180 degree and the speed of 300 mm / min.

In addition, after UV hardening, the adhesive force was measured at 22 degreeC by irradiating an ultraviolet-ray so that the irradiation amount might be 200mJ / cm <2> at the dicing film side using the high pressure mercury lamp ultraviolet irradiation machine (Dymax company, Dymax 2000-EC). Adhesion by temperature before UV curing and 25 ° C. after UV curing of the PSA layer to the adhesive layer is shown in Table 4 below.

division Adhesion by temperature between adhesive layer and PSA layer of dicing film (N / m) UV
After curing Before UV Curing 22 ℃ 22 ℃ 0 ℃ -5 ℃ -10 ℃ -15 ℃ -20 ℃ Preparation Example 2-1 5 148 204 420 449 481 395 Preparation Example 2-2 7 120 206 268 324 350 332 Preparation Example 2-3 8 250 264 324 374 380 327 Preparation Example 2-4 5 134 265 338 360 352 321 Preparation Example 2-5 5 205 443 502 503 560 428 Preparation Example 2-6 5 83 198 254 311 315 274 Preparation Example 2-7 5 150 213 438 461 478 432 Comparative Preparation Example 2-1 4 192 201 198 110 89 50 Comparative Preparation Example 2-2 6 170 392 423 223 127 82 Comparative Preparation Example 2-3 5 70 180 267 302 257 213 Comparative Preparation Example 2-4 2 138 199 430 455 476 365 Comparative Preparation Example 2-5 34 152 211 389 461 432 387 Comparative Preparation Example 2-6 5 50 120 187 290 244 193

Looking at the experimental results of Table 4, in Preparation Example 2-1 to Preparation Example 2-7, while satisfying Equation 1 to Equation 5, showed a higher adhesion than -10 ℃ or -20 ℃ at -15 ℃ .

In contrast, in Comparative Preparation Example 2-1 containing no HEA in the acrylic copolymer resin, the maximum adhesive strength was shown at about 0 ° C., and in Comparative Preparation Example 2-2, there was a problem of showing the maximum adhesive strength of −5 ° C. And, Comparative Preparation Example 2-3 using more than 40 parts by weight of HEA showed the maximum adhesive strength at -10 ℃. In Comparative Preparation Example 2-4 using more than 45% by weight of MOI, the low-temperature adhesive force had a maximum value at -15 ° C and had a proper adhesive force, but after UV curing, the adhesive force was too low to cause chips to scatter. In the case of Comparative Preparation Example 2-5 using less than 10 parts by weight of HEA, the adhesive strength after UV curing was too high, 20 N / m. In addition, in the case of Comparative Preparation Example 2-6 using a PSA resin containing less than 90% by weight of the acrylic copolymer resin, the overall low-temperature adhesive strength was low compared to Preparation Examples 2-1 to 2-7.

Preparation  3-1: Preparation of Polyolefin Film with Antistatic Layer

The 80 μm-thick polyolefin film (Phimax EPG-80) used in Preparation Example 2-1 was deposited by Al (aluminum) on the corona-treated backside of the dicing film in a crucible at 1,000 ° C. and 3 × 10 ⁻⁴ torr. A polyolefin film having an antistatic layer having a thickness of 2 nm was prepared.

Preparation  3-2 ~ Preparation  3-5 and Comparative Preparation  3-1 to 3-3

To prepare a polyolefin film having an antistatic layer formed in the same manner as in Preparation Example 3-1, to form an antistatic layer to a thickness as shown in Table 5 to produce a polyolefin film, respectively.

Experimental Example  3: Measurement of Physical Properties of Polyolefin Film with Antistatic Layer

The transmittance and surface resistance of each of the polyolefin films prepared in Preparation Examples 3-1 to 3-5 and Comparative Preparation Examples 3-1 to 3-3 were measured, and the results are shown in Table 5 below.

In this case, the transmittance was measured by using a UV / visible spectrometer (JASCO V-550) 550nm wavelength range, less than 5% of the UV transmission, because the PSA layer does not have good UV curing, the transmittance If is 5%, it fails.

The surface resistance was measured using a surface resistance meter (Trek 152-1 resistance meter) at 100V voltage.

division Antistatic layer
thickness Transmittance
(550nm wavelength) Antistatic Layer Surface Resistance
(ohm / sq) Preparation Example 3-1 2 nm 29% 4.5ⅹ10 ¹¹ ~ 1ⅹ10 ¹² Preparation Example 3-2 5 nm 22% 7.2ⅹ10 ⁹ ~ 1ⅹ10 ¹⁰ Preparation Example 3-3 10 nm 14% 5.3ⅹ10 ⁴ ~ 1ⅹ10 ⁵ Preparation Example 3-4 20 nm 10% 7.2ⅹ10 ⁴ ~ 1ⅹ10 ⁵ Preparation Example 3-5 30 nm 6% 6.8ⅹ10 ⁴ ~ 1ⅹ10 ⁵ Comparative Preparation Example 3-1 40 nm 4% 7.6ⅹ10 ⁴ ~ 1ⅹ10 ⁵ Comparative Preparation Example 3-2 50 nm 3% 6.9ⅹ10 ⁴ ~ 1ⅹ10 ⁵ Comparative Preparation Example 0 nm 32% 8.6ⅹ10 ¹³ ~ 1ⅹ10 ¹⁴

Looking at the measurement results of Table 5, Preparation Examples 3-1 to 3-5 can be confirmed to have a transmittance of 5% or more and a proper surface resistance. On the contrary, in Comparative Preparation Examples 3-1 and 3-2 in which the antistatic layer exceeded 40 nm, the transmittance was too low at less than 5%, and the surface resistance was not lower than in Preparation Examples 3-5.

Through this experiment, it can be seen that the antistatic layer is formed at a maximum of less than 40 nm, preferably 30 nm or less, at least 1 nm or more, preferably 2 nm or more in terms of transmittance and surface resistance.

Example  1: antistatic die Attach  Manufacture of film

The polyolefin film with an antistatic layer prepared in Preparation Example 3-1 was prepared. After laminating the PSA film prepared in Preparation Example 2-1 on the other surface of the polyolefin film having the antistatic layer formed thereon, the polyester film as a release film was peeled off. Next, by laminating (or laminating) the adhesive film of Preparation Example 1-1 on the PSA film, the antistatic layer 4, the polyolefin film layer 3, the PSA layer 2, and the adhesive layer 1 as shown in FIG. ) Was prepared in the form of laminated DAF film in this order.

Example  2 to Example  5 and Comparative example  1 to Comparative example  7

In the same manner as in Example 1 to prepare a DAF film of the antistatic layer-polyolefin film layer-PSA layer-adhesive layer was laminated in sequence, but was prepared by different dicing film as shown in Table 6.

Example  6

Instead of the dicing film of Preparation Example 3-1, using the dicing film prepared in Preparation Example 3-5, as shown in Figure 2 polyolefin film layer (3)-antistatic layer (4 ')-PSA layer (2)-adhesive layer (1) A DAF film of a laminated form was prepared in this order.

division Polyolefin Film with Antistatic Layer PSA layer Adhesive layer Kinds Antistatic Layer Thickness / Polyolefin Film Thickness Kinds thickness Kinds thickness Example 1 Preparation Example 3-1 2nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Example 2 Preparation Example 3-2 5nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Example 3 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Example 4 Preparation Example 3-4 20nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Example 5 Preparation Example 3-5 30nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Example 6 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-4 10 μm Preparation Example 1-1 20 ㎛ Example 7 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-4 10 μm Preparation Example 1-1 4.5㎛ Example 8 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-4 10 μm Preparation Example 1-1 55 μm Comparative Example 1 Comparative Preparation Example 3-1 40nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Comparative Example 2 Comparative Preparation Example 3-2 50nm / 80㎛ Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Comparative Example 3 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-4 10 μm Preparation Example 1-1 2 μm Comparative Example 4 Preparation Example 3-3 10nm / 80㎛ Preparation Example 2-4 10 μm Preparation Example 1-1 65 μm Comparative Example 5 Preparation Example 3-3 10nm / 80㎛ Comparative Preparation Example 2-1 10 μm Preparation Example 1-1 20 ㎛ Comparative Example 6 Preparation Example 3-3 10nm / 80㎛ Comparative Preparation Example 2-2 10 μm Preparation Example 1-1 20 ㎛

Experimental Example  4 : Adhesive layer Peeling voltage Adhesion measurement before and after UV curing, Pickup  Measure

(One) Peeling voltage  Measure

The difing film in which the DAF films prepared in Examples and Comparative Examples were irradiated with UV and placed on the surface of the dicing film so as to contact the ITO substrate, and the adhesive film was peeled off at a speed of 300 mm / min, and the adhesive film was peeled off. The large voltage of the adhesive surface was measured. The large voltage measurement was measured at a distance of 30 mm from the dicing film using STATIRON DZ-4 (SHISHIDO Co., Ltd.) equipment and the results are shown in Table 7 below.

For reference, in the case of Comparative Example 3, there is no antistatic layer.

(2) before and after UV curing On the adhesive layer  Adhesion Measurement of PSA Layers for

The adhesion of the dicing film to the adhesive layer before and after UV curing of the DAF films prepared in Examples and Comparative Examples was measured and the results are shown in Table 7 below. At this time, the adhesive force was roll laminated on the back surface of a 500-inch-thick 8-inch silicon wafer (wafer treated with # 2300 grinding machine by DFD-840 grinding machine manufactured by Disco) in the direction of the adhesive layer of the DAF film, Peel strength with respect to the adhesive layer of the PSA layer of the dicing film before and after UV hardening was measured by peeling a PSA layer and an adhesive layer 180 degrees at 300 mm / min. For reference, after UV curing, the adhesive force of the PSA layer is weakened, so that peeling with the adhesive layer (adhesive film) becomes easy.

division Peeling Voltage (kV) Adhesion at 22 ° C. of the PSA layer to the adhesive layer (N / m) Before UV Curing
(22 ℃) After UV curing
(22 ℃) Example 1 0.8 kV 150 N / m 7 N / m Example 2 0.3 kV 150 N / m 7 N / m Example 3 0.3 kV 150 N / m 7 N / m Example 4 0.3 kV 150 N / m 8 N / m Example 5 0.3 kV 150 N / m 15 N / m Example 6 0.3 kV 160 N / m 5 N / m Example 7 0.3 kV 150 N / m 4 N / m Example 8 0.3 kV 170 N / m 15 N / m Comparative Example 3 0.6 kV 160 N / m Not measurable
(Wafer peeling) Comparative Example 4 0.5 kV 175 N / m 26 N / m Comparative Example 5 0.3 kV 192 N / m 5 N / m Comparative Example 6 0.3 kV 170 N / m 5 N / m

In the measurement results of Table 7, the comparative example 3 without the antistatic layer showed a high peeling voltage of 1.2 kV. In this case, when the peeling voltage is high, device destruction due to charge charging during semiconductor packaging was observed. There is a problem that may occur. In Examples 1 to 8 and Comparative Examples 3 to 6 in which the antistatic layer was formed, a low peeling voltage of 0.8 kV or less was shown.

And, Examples 1 to 8 showed a low adhesive strength of less than 20 N / m after UV curing, it was confirmed that the proper peelability with the adhesive film (adhesive layer). However, in Comparative Example 3, in which the thickness of the adhesive layer was less than 3 μm, the adhesive force between the contact layer and the PSA layer could not be measured due to insufficient adhesive force with the wafer, and the thickness of the adhesive layer exceeded 60 μm. In the case of Comparative Example 4 having a thickness of 65 μm, there was a problem of having a high adhesive strength exceeding 20 N / m even after UV curing.

Experimental Example  5: DBG and SDBG  Fairness test

The maximum adhesive strength by temperature and DAF pick-up of the DAF films of Examples and Comparative Examples were measured.

(1) Measuring the maximum adhesive strength by temperature

The maximum adhesive strength (-20 ° C, -15 ° C, -10 ° C, -7 ° C, -3 ° C, 0 ° C and 5 ° C) between the adhesive layer and the PSA layer of the DAF film was measured, thereby expanding expansion) ensures the separation in the process and the occurrence of the lifting and the adhesive layer and the PSA layer was confirmed, the results are shown in Table 8 below. At this time, the adhesive force represents the temperature when the maximum adhesive force and the maximum adhesive force.

(2) chip breakup

Chip splitting was performed by laminating the DAF film at 70 ° C with a ring frame for fixing the 8-inch wafer having a thickness of 100um. Using a dicing machine (Disco DFD-6361), the wafer was cut to a size of 9 mm x 12 mm (width x length), leaving a thickness of 20 um. The ring frame on which the cut wafer and the DAF were laminated was placed in an expand apparatus at -10 ° C, and the dicing film was expanded dicing at an expand speed of 80 mm / sec and an expand height of 10 mm.

Good (O) and less than 90% were measured as defective (X) for 90% or more of the actual number of lines that were actually segmented by expand relative to the total number of lines cut by the blade. Then, the lifted between the adhesive layer and the dicing film PSA pressure-sensitive adhesive of the edge of the divided chip is measured as "not generated" and less than 1mm "developed" and the results are shown in Table 8 below.

(3) DAF  Film Pickup  Measure

The pickup property was UV-irradiated in the same manner as in the above Experimental Example, and the wafer and the DAF film segmented in Experimental Example 5- (2) were picked up at 22 ° C. using a pickup equipment (SPA-300 manufactured by Shinkawa Co., Ltd.). At this time, the height of the needle pin was picked up at 0.25 mm and 0.30 mm and marked as good (O) when the pick-up success rate was more than 95%, and bad (X) when less than 95%.

division Adhesion by temperature Excitation
Whether Chip Breaking Pickup Adhesive force value
(gf / 25mm) Temperature 0.25mm 0.30mm Example 1 481 -15 Not Occurred O O O Example 2 481 -15 Not Occurred O O O Example 3 481 -15 Not Occurred O O O Example 4 481 -15 Not Occurred O O O Example 5 481 -15 Not Occurred O O O Example 6 360 -10 Not Occurred O O 0 Example 7 352 -10 Not Occurred O O O Example 8 392 -10 Not Occurred O O O Comparative Example 1 481 -15 Not Occurred O X X Comparative Example 2 481 -15 Not Occurred O X X Comparative Example 3 300 -10 Not Occurred O Can't pick up Can't pick up Comparative Example 4 398 -10 Not Occurred X Can't pick up Can't pick up Comparative Example 5 198 -5 Occur O X X Comparative Example 6 423 -5 Occur O X O

Looking at the measurement results of Table 8, in the case of Example 1 to Example 8, the lifting does not occur, the chip was not divided. It also showed excellent pickup properties.

On the contrary, in Comparative Example 5 and Comparative Example 6 in which the PSA layer was formed of the PSA resin of Comparative Preparation Example 2-1 or Comparative Preparation Example 2-2, the temperature showing the maximum adhesive force was higher than that of Example, The results were bad.

In addition, Comparative Examples 1 and 2, in which the thickness of the antistatic layer was 40 nm and 50 nm, respectively, also showed poor pickup performance.

In Comparative Example 3, in which the adhesive layer had a thickness of 2 μm, the adhesive force between the adhesive layer and the wafer was not sufficient, so there was a problem in that only the wafer was picked up without the adhesive layer in the pickup. The adhesive force between the adhesive layer and the PSA layer is high, the pick-up property is not good, and the chip is not broken.

1: adhesive layer 2: PSA adhesive layer
3: polyolefin film layer 4, 4 ': antistatic layer
10: dicing film 30: release film layer
100, 200, 300, 400: Antistatic DAF

Claims (19)

A dicing film including an antistatic layer, a polyolefin film (PO film, Polyolefin film) layer, and a pressure sensitive adhesive (PSA) layer; And an adhesive layer laminated on the PSA layer of the dicing film, wherein the dicing film is
An antistatic layer, a polyolefin film layer and a PSA layer are laminated in this order, or
A polyolefin film layer, an antistatic layer, and a PSA layer are laminated | stacked in order, The antistatic die attach film characterized by the above-mentioned.
The antistatic die attach film of claim 1, wherein the antistatic layer comprises at least one selected from Al, Al ₂ O ₃ , indium tin oxide (ITO), Ni, and Ag.
According to claim 1, wherein the adhesive layer has an average thickness of 3㎛ ~ 60㎛, the PSA layer is 5㎛ ~ 30㎛, the dicing film layer is 60㎛ ~ 150㎛, the antistatic layer has an average thickness of 1 nm Antistatic die attach film, characterized in that ~ ~ 30nm.
The antistatic die attach film according to claim 1, wherein the adhesive layer comprises an adhesive in a B-stage state or an adhesive film in a B-stage state.
According to claim 4, wherein the adhesive is 60 to 75% by weight of the thermoplastic resin, 10 to 25% by weight of the epoxy resin, 2 to 10% by weight of the curing agent, 4 to 15% by weight of the inorganic filler, 0.1 to 2% by weight of the curing accelerator and the coupling An antistatic die attach film comprising 0.1 to 4% by weight of a ring agent.
The method of claim 1, wherein when the thickness of the antistatic layer is 5 ~ 30nm, the antistatic die attach film (ectrostatic voltage) of the adhesive layer, characterized in that 0.1 kV ~ 0.8 kV.
The antistatic die attach film of claim 1, wherein the surface resistance of the antistatic layer is 1 × 10 ² to 1 × ^{10 12} ohm / sq.
The method according to claim 1, wherein the storage modulus before UV curing of the adhesive layer satisfies the following equation (6);
[Equation 6]
20 ≤ storage modulus value (Mpa) at 25 ° C. before curing of the adhesive layer / storage modulus value at 130 ° C. before curing of the adhesive layer (Mpa) ≤ 90
According to Equation 1, the storage modulus value is 20mmⅹ5mm (horizontal length) of the specimen using a dynamic thermomechanical analyzer (Perkin Elmer, Diamond DMA), measuring temperature -30 ℃ ~ 300 ℃ (heating rate 10 ℃ Per minute) and measurement frequency of 10 Hz.
According to claim 1, wherein the adhesive layer has a storage modulus value of at least 3 MPa at 260 ℃ after UV curing,
The adhesive layer is an antistatic die attach film, characterized in that the shear adhesive strength at 260 ℃ after curing 4 ~ 10 MPa when the thickness is 20㎛.
According to claim 1, wherein the adhesive force at 22 ℃ between the PSA layer and the adhesive layer of the dicing film is 80 ~ 300 N / m before UV (ultraviolet) curing, the adhesive strength at 22 ℃ after UV curing 20 N / m The antistatic die attach film characterized by the following.
The antistatic die attach of claim 10, wherein the adhesive force between the PSA layer and the adhesive layer has a maximum adhesive force at a temperature of −15 ° C. to −7 ° C., and the maximum adhesive force is 300 to 700 N / m. film.
The method according to claim 10, wherein the adhesive force between the PSA layer and the adhesive layer of the dicing film satisfies the following equation 1 to equation 5 before UV curing,
An antistatic die attach film characterized in that the adhesion at -13 ° C to -15 ° C is higher than the adhesion at -7 ° C to -10 ° C;
Equation 1
Adhesion at 150 N / m ≤ 0 ° C ≤ 470 N / m
[Equation 2]
Adhesion at 220 N / m ≤ -3 ° C to -5 ° C ≤ 520 N / m
[Equation 3]
Adhesion at 300 N / m ≤ -7 ° C to -10 ° C ≤ 540 N / m
[Equation 4]
305 N / m ≤ -13 ° C -15 ° C adhesive force ≤ 700 N / m
[Equation 5]
Adhesion at -18 ° C to -20 ° C ≤ 500 N / m
The antistatic die attach film of claim 1, wherein the PSA layer is formed of a PSA resin including 90 to 97 wt% of an acrylic copolymer resin, 2 to 8 wt% of a thermosetting agent, and 0.1 to 2 wt% of a photoinitiator. .
According to claim 13, The acrylic copolymer resin is based on 100 parts by weight of 2-ethylhexyl acrylate, 10 to 40 parts by weight of 2-hydroxyethyl acrylate, 10 to 45 parts by weight of 2-methacryloyloxyethyl isocyanate An antistatic die attach film comprising a copolymerized copolymerized copolymer.
The antistatic die attach film of claim 14, wherein the copolymer is a copolymer obtained by further copolymerizing at least one selected from ethylhexyl methacrylate and hydroxylethyl methacrylate.
The method according to claim 15, wherein the ethylhexyl methacrylate is included in an amount of 5 to 135 parts by weight based on 100 parts by weight of 2-ethylhexyl acrylate,
The hydroxylethyl methacrylate is an antistatic die attach film, characterized in that it comprises 3 to 30 parts by weight based on 100 parts by weight of 2-ethylhexyl acrylate.
1 step of manufacturing a dicing film comprising an antistatic layer, a polyolefin film layer, a PSA layer; And
Integrating an adhesive film on the PSA layer of the dicing film by laminating or integral, or casting and drying the adhesive on the PSA layer of the dicing film to form an adhesive layer;
The dicing film is a method for producing an antistatic die attach film, characterized in that the antistatic layer, the polyolefin film layer and the PSA layer are laminated in sequence, or the polyolefin film layer, the antistatic layer and the PSA layer are laminated in this order. .
18. The method of claim 17, wherein the adhesive film or adhesive layer is in a B-stage state.
In the dicing before grinding (DBG) or stealth dicing before grinding (SDBG) wafer dicing process,
The anti-die die attach film of any one of Claims 1-16 is used, The wafer dicing process characterized by the above-mentioned.

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