JP2023088239A - Spacer film and method for forming spacer using the same - Google Patents

Abstract

To provide a spacer film suppressing a die recognition failure occurring in a dicing process and achieving an improvement in picking up properties, and a method for forming a spacer using the spacer film.SOLUTION: The present invention relates to a spacer film applied to a multichip package, and a method for forming a spacer using the spacer film. The spacer film according to the present invention includes a first film having a glass transition temperature (Tg) of 130°C or more, and an adhesive layer arranged at a lower part of the first film. The spacer film according to the present invention includes the first film instead of a dummy wafer and has a value of (coefficient of thermal expansion/storage modulus) of 1-15 ppm/GPa. Thus, a die recognition failure occurring in a dicing process is suppressed and picking up properties can be improved.SELECTED DRAWING: Figure 5

Description

The present invention relates to a spacer film applied to a multi-chip package and a spacer forming method using the same.

2. Description of the Related Art With the development of semiconductor device manufacturing technology, much research has been conducted on the miniaturization and multi-functionalization of electronic devices. A multi-chip package (MCP) technology is one of semiconductor chip packaging technologies, and is a technology for realizing the same kind of semiconductor chips or different kinds of semiconductor chips in one package. Multi-chip packaging technology can achieve high-speed transmission in a small package area, and has advantages in size and weight compared to implementing each semiconductor chip in a separate package.

In order to obtain the effect of reducing the size of a multi-chip package, it is necessary to stack a plurality of semiconductor chips and arrange them in one package. Spacers are used here. For example, in a package in which two semiconductor chips are stacked, one of the semiconductor chips is directly attached to the package substrate, but the other semiconductor chip is not directly attached to the package substrate. A spacer plays a role of supporting a semiconductor chip that cannot be directly attached to such a package substrate.

Spacers are usually made of metal, polymer, photosensitive resist, or the like. When the spacers are made of metal or photosensitive resist, a method of depositing or coating the metal or photosensitive resist on the package substrate and then removing portions other than the spacers by etching can be used. When the spacer is made of metal or polymer, a method of fabricating the spacer in a predetermined shape and adhering it on the package substrate can be used.

The method of forming spacers by etching after deposition or coating of metal or photosensitive resist not only requires a complicated process such as photolithography, but also poses a problem of waste of materials. In the method of fabricating a spacer of a predetermined size and bonding it onto a package substrate, not only is it difficult to accurately fabricate a spacer of a desired size, but it is also difficult to accurately attach the spacer to the package substrate. There's a problem.

There is also a method of using (cutting) a dummy wafer to fabricate a spacer and bonding it onto a package substrate, but this method poses a problem of waste of the dummy wafer.

On the other hand, instead of using a dummy wafer, it is possible to use a polymer film containing a component such as polyimide as a spacer. Warp occurs, die recognition failure occurs, and pick-up property deteriorates.

An object of the present invention is to provide a spacer film that enables a dicing process without using a dummy wafer, suppresses die recognition failure, and improves pick-up properties.

Another object of the present invention is to provide a method of forming a spacer that enables a highly efficient dicing process without using a dummy wafer.

Another object of the present invention is to provide a multi-chip package that does not use dummy wafers.

The technical problem to be achieved by the present invention is not limited to the above problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A spacer film according to an exemplary embodiment includes a first film having a glass transition temperature (Tg) of 130° C. or higher, and an adhesive layer disposed under the first film. meet.

[Formula 1]
1 ppm/GPa ≤ (thermal expansion coefficient/storage modulus) ≤ 15 ppm/GPa

In Equation 1, the coefficient of thermal expansion and the storage modulus are values measured at 25°C.

In some embodiments, the coefficient of thermal expansion may be between 10 ppm and 50 ppm.

In some embodiments, the storage modulus may be between 2 GPa and 10 GPa.

In some embodiments, the first film can include at least one of polyimide, polyetheretherketone, polyamideimide, polyphenylene sulfide, polyphthalamide, polysulfone, polyethersulfone, and polyetherimide. can.

In some embodiments, the first film can include a coating layer on the bottom.

In some embodiments, the coating layer comprises at least one of a compound containing polyimide functional groups, a compound containing polyamideimide functional groups, a compound containing epoxy functional groups, and a compound containing urethane acrylate functional groups. be able to.

In some embodiments, the adhesive layer can include at least one of an acrylic compound and an epoxy resin.

In some embodiments, the spacer film may further include a first pressure-sensitive adhesive layer disposed below the adhesive layer.

In some embodiments, the first pressure sensitive adhesive layer can include an acrylic compound.

In some embodiments, the edges of the top surface of the first pressure sensitive adhesive layer may be exposed.

In some embodiments, the attachment force between the first pressure-sensitive adhesive layer and the adhesive layer is 20-200 N/m before UV curing of the first pressure-sensitive adhesive layer; After UV curing of the pressure-sensitive adhesive layer, it may be 15 N/m or less.

In some embodiments, the spacer film may further include a second film disposed below the first pressure-sensitive adhesive layer.

In some embodiments, the second film can include polyolefin-based resin.

Some embodiments may further include a second pressure-sensitive adhesive layer disposed on the first film, and a cover film disposed on the second pressure-sensitive adhesive layer.

A method for forming spacers according to an exemplary embodiment includes a fixing step of fixing the spacer film to a frame, a dicing step of dicing the spacer film into individual pieces, and separating the individual pieces from the resulting pieces. a picking up step of picking up spacers composed of a film and an adhesive layer; and a mounting step of mounting the picked up spacers onto a package substrate.

In some embodiments, the spacer film further comprises a first pressure-sensitive adhesive layer disposed under the adhesive layer, the top edge of the first pressure-sensitive adhesive layer being exposed. , the frame may be positioned on the edge of the top surface of the first pressure sensitive adhesive layer.

A multi-chip package according to an exemplary embodiment includes a package substrate, a spacer including the spacer film of claim 1 arranged on the package substrate, and a first semiconductor chip unit arranged on the package substrate. a second semiconductor chip unit stacked on the spacer and the first semiconductor chip unit; a chip pad of the first semiconductor chip unit and a first substrate pad corresponding thereto; wires electrically connecting chip pads and corresponding second substrate pads; and a package body sealing the first semiconductor chip unit, the second semiconductor chip unit, the wires and the spacers.

The spacer film according to the present invention includes a first film having a glass transition temperature (Tg) of 130 ° C. or higher instead of the dummy wafer, and the value obtained by dividing the thermal expansion coefficient by the storage elastic modulus is 1 ppm / GPa ~ 15 ppm/GPa.

As a result, the spacer film according to the present invention can suppress die recognition failure that occurs in the pick-up process after dicing, facilitate separation and pick-up between chips in the pick-up device, and improve reliability after package assembly is completed. can improve sexuality.

In addition, individualized spacers of a desired size can be easily produced from the spacer film according to the present invention by a dicing process.

In addition, according to the method of forming spacers according to the present invention, the individualized spacers can be easily attached to the package substrate by the pick-up process and the attachment process.

In addition, the present invention can provide a multi-chip package that does not use a dummy wafer by using the spacer film.

FIG. 1 is a cross-sectional view schematically showing an example of a multi-chip package including spacers according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a multi-chip package including spacers according to another embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a multi-chip package including spacers according to still another embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a multi-chip package including spacers according to still another embodiment of the present invention. FIG. 5 is a cross-sectional view schematically showing a spacer film according to one embodiment of the present invention. FIG. 6 is a cross-sectional view schematically showing a spacer film according to another embodiment of the present invention. FIG. 7 schematically shows a method of forming spacers using a dicing process according to the present invention. FIG. 8 is a plan view corresponding to (a), (b), and (c) of FIG.

In describing the present invention, if it is determined that the specific description of related known technologies may obscure the gist of the present invention, the detailed description will be omitted. In addition, the terms described below are defined in consideration of the functions of the present invention, and may differ according to the user's or operator's intentions or customs. Therefore, the definition should be based on the content throughout this specification.

The technical idea of the present invention is determined by the claims. Moreover, the following embodiments are merely means for efficiently explaining the technical idea of the present invention to those skilled in the art.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings, but these are merely examples and do not limit the present invention.

FIG. 1 is a cross-sectional view schematically showing an example of a multi-chip package including spacers.

Referring to FIG. 1 , a first semiconductor chip unit 120 is arranged on a package substrate 110 . The first semiconductor chip unit 120 may include a first adhesive layer 121 and a first semiconductor chip 122 . The first adhesive layer 121 serves to attach the first semiconductor chip 122 to the package substrate 110 . The first semiconductor chip unit 120 can be electrically connected to the package substrate 110 by connecting the chip pads and the corresponding first substrate pads via wires 125 .

A spacer 130 is arranged around the first semiconductor chip unit 120 . Spacer 130 includes adhesive layer 131 and support 132 . Adhesive layer 131 serves to attach support 132 to the substrate.

A second semiconductor chip unit 140 is arranged on the spacer 130 . The second semiconductor chip unit 140 may include a second adhesive layer 141 and a second semiconductor chip 142 . The second adhesive layer 141 serves to attach the second semiconductor chip 142 to the support 132 of the spacer 130 . The second semiconductor chip unit 140 can be electrically connected to the package substrate 110 by connecting the chip pads and the corresponding second substrate pads via wires 145 . As another example, the second semiconductor chip 142 may be electrically connected to the package substrate 110 through via holes penetrating the spacer 130 .

After the first semiconductor chip unit 120, the spacer 130 and the second semiconductor chip unit 140 are arranged on the package substrate 110, and the wire bonding process is performed, the package body 150 is formed to seal them. The package body 150 can be made of an encapsulant such as epoxy resin.

As shown in FIG. 1, the height of spacer 130 may be higher than the height of first semiconductor chip unit 120 . As a result, the second semiconductor chip units 140 can be stacked using the spacers 130 as supports. As another example, the height of the spacer 130 may be the same as the height of the first semiconductor chip unit 120 . Moreover, since the height of the spacer 130 is the same as the height of the first semiconductor chip unit 120, the effect of embedding the first semiconductor chip unit 120 by the spacer 130 and the second semiconductor chip unit 140 can be obtained. can.

2 to 4 are cross-sectional views schematically showing other examples of multi-chip packages including spacers.

2 to 4, the second semiconductor chip unit ("140-1" to "140-4" in FIG. 2, "140-1" to "140-5" in FIG. 3, "140-1" in FIG. to 140-7) are electrically connected to another second semiconductor chip unit or package substrate 110 through wires (not shown) or via holes (not shown), as in the example shown in FIG. can be connected.

In the case of the multi-chip package shown in FIGS. 2 to 4 as well, semiconductor chip units can be stacked via spacers 130 arranged on the package substrate 110. FIG.

FIG. 5 is a cross-sectional view schematically showing a spacer film according to one embodiment of the present invention. Referring to FIG. 5 , the illustrated spacer film includes a first film 510 having a glass transition temperature (Tg) of 130° C. or higher and an adhesive layer 520 , which is disposed below the adhesive layer 520 . It can further include a first pressure sensitive adhesive layer 535 . A spacer film according to an embodiment of the present invention satisfies Equation 1 below.

[Formula 1]
1 ppm/GPa ≤ (thermal expansion coefficient/storage modulus) ≤ 15 ppm/GPa

In Equation 1, the thermal expansion coefficient and storage modulus are values measured at 25°C.

The value of (thermal expansion coefficient/storage modulus) in Equation 1 is preferably 1 to 30 ppm/GPa, more preferably 1 to 15 ppm/GPa. Within the range of the above values, it is easy to ensure pick-up processability and high-temperature reliability process after moisture absorption.

The thermal expansion coefficient is obtained by using a TMA (Thermomechanical Analysis, manufacturer: TA, model name: TMA Q400) device for a spacer film cut to 4 mm × 16 mm, and increasing the temperature from -30 ° C. at a rate of 10 ° C./min. However, it may be measured at 25°C. The thermal expansion coefficient is preferably 10 ppm to 50 ppm. If the thermal expansion coefficient exceeds 50 ppm, the expansion of the film increases during a high-temperature soldering process, causing interfacial peeling, which may reduce reliability.

The storage elastic modulus (E') was measured by using a DMA (dynamic mechanical analyzer, manufacturer: TA, model name: DMA850) device for a spacer film cut to 5 mm × 20 mm, at a temperature range of -30 ° C. to 10 ° C./min. and measured at 25°C. The storage modulus is preferably 1 GPa to 30 GPa, more preferably 2 GPa to 10 GPa. If the storage elastic modulus is less than 2 GPa, the pickup process cannot be performed due to poor die recognition during expansion and the height of the needle pin of the pickup device. If the storage elastic modulus exceeds 10 GPa, the hardness may increase too much to produce a roll-like product.

The first film The first film 510 is the part that becomes the support 132 of the spacer 130 of FIGS. 1-4.

The first film 510 preferably has a glass transition temperature (Tg) of 130° C. or higher. When the glass transition temperature is 130° C. or higher, resistance to thermal deformation can be imparted in a high-temperature soldering process, and peeling at the interface can be suppressed, thereby improving reliability.

If the glass transition temperature is 130° C. or higher, the desired effects of the present invention can be achieved, so the upper limit is not particularly limited, but considering the material of the first film, it may be 500° C. or lower.

The glass transition temperature was measured by using a DMA (dynamic mechanical analyzer, manufacturer: TA, model name: DMA850) device for the first film cut to 5 mm x 20 mm under the condition of a temperature increase rate of 10 ° C./min. may be The glass transition temperature is the temperature at which tan δ of the first film is maximized.

Also, the first film 510 preferably has heat resistance. Therefore, in the present invention, the first film 510 is limited to those having a weight loss rate of 2% or less at 200°C and a coefficient of linear expansion of 50 ppm/°C or less at 100°C or less. If the weight loss rate at 200°C exceeds 2% or the linear expansion coefficient at 100°C or lower exceeds 50 ppm/°C, it can be said that the heat resistance is not good.

The heat-resistant first film 510 may include at least one of polyimide, polyetheretherketone, polyamideimide, polyphenylene sulfide, polyphthalamide, polysulfone, polyethersulfone, and polyetherimide. can. Among them, it is more preferable to use polyimide or polyetheretherketone, which are more excellent in heat resistance, as the material for the first film.

The first film 510 can have a single layer structure. As another example, the first film 510 can have a multilayer structure.

The first film 510 may include a coat layer underneath. The coating layer may have a higher elastic modulus or shrinkage rate than the first film 510 . The coating layer may preferably include at least one of a polyimide functional group-containing compound, a polyamideimide functional group-containing compound, an epoxy functional group-containing compound, and a urethane acrylate functional group-containing compound. The compound can be included in the form of a cured product.

The thickness of the first film layer can be determined by the thickness of the target spacer support (“132” in FIG. 1), and may range from 2 μm to 100 μm, but is not limited thereto. do not have.

Adhesive layer The adhesive layer 520 is the part that becomes the adhesive layer 131 of the spacer 130 in FIGS.

The adhesive layer 520 is arranged under the first film 510 . Adhesive layer 520 can have a thickness of about 3-60 μm, but is not limited thereto.

In the present invention, the adhesive layer 520 can contain an acrylic compound. Adhesive layer 520 may also include an epoxy resin for curing. As the epoxy resin, one or more of bisphenol A type, bisphenol F type, bisphenol S type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type, orthocresol novolak type, glycidylamine type, etc. may be used. can be done.

Also, the adhesive layer 520 may further include one or more additives. Examples of additives include curing agents (phenolic resins, amines, etc.), inorganic particles (silica, aluminum hydroxide, alumina, titanium dioxide, calcium carbonate, etc.), curing accelerators, silane coupling agents, and the like. It is not limited to these.

The acrylic compound that can be used for the adhesive layer 520 and the first pressure-sensitive adhesive layer 535 and the second pressure-sensitive adhesive layer 545, which will be described later, preferably contains a monomer derived from a (meth)acrylic acid ester. .

Examples of the monomer (meth)acrylic acid ester include (meth)acrylic acid alkyl ester, (meth)acrylic acid cycloalkyl ester, and (meth)acrylic acid aryl ester.

Acrylic compounds include carboxy group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, acrylonitrile Containing monomers and the like can be further included.

Also, the acrylic compound may further include one or more polyfunctional monomers. Polyfunctional monomers include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy (meth)acrylate (i.e. polyglycidyl (meth)acrylate), polyester ( meth)acrylates, urethane (meth)acrylates, and the like.

Second Film A spacer film according to an exemplary embodiment of the present invention may further include a second film 530 disposed below the adhesive layer 520 .

A first pressure sensitive adhesive layer 535 can be disposed between the second film 530 and the adhesive layer 520 . The first pressure sensitive adhesive layer 535 can be cast coated and dried directly onto the second film 530 or laminated to the second film 530 .

The second film 530 may serve as a support during the dicing process. The thickness of the second film 530 may be adjusted to 40 μm or more to ensure expandability and pick-up properties. On the other hand, if the thickness of the second film 530 is more than 300 μm, it may cause expanding defects and pick-up defects. The thickness of the second film 530 may range from 40-300 μm, preferably 50-250 μm, more preferably 60-200 μm, most preferably 70-150 μm.

The second film 530 may use polyolefin resin. Specifically, the second film 530 is made of low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolypropylene, polybutene, polymethylpentene, ethylene-acetic acid. One of vinyl copolymers, ionomer resins, ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-butene copolymers, and ethylene-hexene copolymers It can be formed of a material including the above.

The second film 530 may have a single layer structure, or alternatively may have a multi-layer structure.

The first pressure-sensitive adhesive layer 535 can be formed with a thickness of about 5-30 μm, but is not limited thereto. The first pressure sensitive adhesive layer 535 can contain an acrylic compound. However, unlike the adhesive layer 520, the first pressure-sensitive adhesive layer 535 may not contain epoxy resin.

Also, the first pressure-sensitive adhesive layer 535 may further include one or more additives. Additives include, but are not limited to, thermal curing agents such as isocyanate curing agents and photoinitiators such as benzophenone.

The first pressure-sensitive adhesive layer 535 may exist in a B-stage state before UV curing in the dicing process.

On the other hand, the attachment force between the first pressure-sensitive adhesive layer 535 and the adhesive layer 520 can be 20 to 200 N/m before UV curing of the first pressure-sensitive adhesive layer and 15 N/m or less after UV curing. can. This is for picking up only the first film 510 and the adhesive layer 520 separated into individual pieces in the pickup process after dicing. Such control of the attaching force of the first pressure-sensitive adhesive layer 535 can be performed, for example, by controlling the adhesive component. For example, the acrylic compound of the first pressure-sensitive adhesive layer 535 is 10 to 40 parts by weight of 2-hydroxyethyl acrylate and 10 to 45 parts by weight of 2-methacryloyloxyethyl isocyanate per 100 parts by weight of 2-ethylhexyl acrylate. It may contain a copolymer obtained by a copolymerization reaction in parts by weight.

On the other hand, referring to FIG. 5, the edge of the top surface of the first pressure sensitive adhesive layer 535 may be exposed. This is for facilitating fixing of the spacer film to the ring frame in the dicing process. This will be described later with reference to FIG.

FIG. 6 is a cross-sectional view schematically showing a spacer film according to another embodiment of the present invention.

The spacer film shown in FIG. 6 includes a first film 510, an adhesive layer 520, a second film 530, and a first pressure-sensitive adhesive layer 535, similar to the spacer film shown in FIG. The first film 510, the adhesive layer 520, the second film 530, and the first pressure-sensitive adhesive layer 535 in the spacer film shown in FIG. 6 are the same as those in FIG. 5, so description thereof will be omitted.

The spacer film shown in FIG. 6 further includes a cover film 540 and a second pressure sensitive adhesive layer 545 .

Cover Film Cover film 540 functions as a protective film to protect first film 510 before the dicing process. The cover film 540 is previously removed in the dicing process. The cover film 540 can be made of materials such as polyethylene terephthalate, polyethylene, polypropylene, polyvinyl chloride, polycarbonate, polyimide, but is not limited to these.

A second pressure sensitive adhesive layer 545 can be disposed between the cover film 540 and the first film 510 .

The second pressure-sensitive adhesive layer 545 can be formed with a thickness of about 3-30 μm, but is not limited thereto. Like the first pressure-sensitive adhesive layer 535, the second pressure-sensitive adhesive layer 545 may contain an acrylic compound and may not contain an epoxy resin. The second pressure-sensitive adhesive layer 545 may further include at least one additive such as a curing agent such as a phenolic resin, amines, or a silane coupling agent.

It should be noted that, referring to FIG. 6, the edge of the bottom surface of the second pressure sensitive adhesive layer 545 may be exposed. This is to facilitate removal of the cover film 540 and the second pressure sensitive adhesive layer 545 just before the dicing process.

Method of Forming Spacers FIG. 7 schematically shows a method of forming spacers using the dicing process according to the present invention. FIG. 8 is a plan view corresponding to (a), (b), and (c) of FIG. 7, and will be referred to when describing the method of FIG.

Referring to FIG. 7, the method of forming a spacer according to the present invention includes a fixing step, a dicing step, a pick-up step and an attachment step.

First, as in the example shown in FIG. 7A, a spacer film including a first film 510, an adhesive layer 520, a first pressure-sensitive adhesive layer 535, and a second film 530 is provided from above. For example, by removing the second pressure-sensitive adhesive layer 545 and the cover film 540 from the spacer film shown in FIG. 6, a spacer film such as the example shown in FIG. 7(a) can be provided.

After that, the spacer film is fixed as in the example shown in FIGS. 7(b) and 8(b). A frame 610, such as a ring frame, can be used to secure the spacer films. On the other hand, if the edge of the top surface of the first pressure-sensitive adhesive layer 535 is exposed in the spacer film, the frame 610 can be easily placed on the edge of the top surface of the first pressure-sensitive adhesive layer 535 .

Thereafter, as in the example shown in FIG. 7(c), the spacer film is diced along predetermined cutting lines SL using a dicing saw 601 or a laser. INDUSTRIAL APPLICABILITY As described above, the spacer film according to the present invention can prevent the spacer film from being warped upward at the edge of the chip during expanding, thereby preventing expanding defects and pick-up defects. can be suppressed.

Thereafter, as in the example shown in FIG. 7(d), using the pushing means 620 and the adsorption means 630, the spacers composed of the first film 510 and the adhesive layer 520 are picked up from the singulated product.

After that, a spacer composed of a first film 510 and an adhesive layer 520 is attached on the package substrate 110, as in the example shown in FIG. 7(e).

<Example>
Hereinafter, preferred examples will be presented to aid understanding of the present invention, but these examples are merely illustrative to facilitate understanding of the present invention, and do not limit the content of the present invention. do not have.

In order to manufacture the adhesive film for spacers, a film for spacers comprising a first film (polyimide), an acrylic-epoxy adhesive layer, an acrylic pressure-sensitive adhesive layer and a second film (polyethylene film) was produced. As the first film, a film with a coat layer formed thereon and a film without a coat layer were used.

The coefficient of thermal expansion was measured by using a TMA apparatus at 25° C. with a heating rate of 10° C./min on a 4 mm×16 mm test piece of the produced spacer film.

The storage elastic modulus was measured using a DMA apparatus at 25° C. by preparing a test piece having a size of 5 mm×20 mm from the produced spacer film, and using a method with a heating rate of 10° C./min.

The glass transition temperature was measured by preparing a test piece of 5 mm×20 mm in size from the first film and using a DMA device under the conditions of a heating rate of 10° C./min.

Table 1 below shows the measurement results of the coefficient of thermal expansion, storage modulus and glass transition temperature of each sample.

Evaluation of Spacer Adhesive Film The spacer film was then secured by bonding a ring frame to the top edge of the acrylic pressure sensitive adhesive layer. After that, using a dicing machine DFD-6361 (manufactured by Disco), a dicing step was performed to divide each test piece into individual spacers of 9 mm×12 mm. After that, using a pick-up device SPA-300 (manufactured by Shinkawa Co., Ltd.), the individual spacers were expanded and picked up.

The following evaluations were performed, and the results are shown in Table 2.

Evaluation of chip recognition: In order to facilitate separation and pickup between chips in a pick-up device after dicing, an expanding process was performed to expand the second film, and the height of the expanding ring was 3 mm. We measured the chip recognition rate in A recognition rate of 95% or more was evaluated as good (O), and a recognition rate of less than 95% was evaluated as poor (X).

Evaluation of pick-up property: The height of the needle pin of the pick-up device was set to 0.35 mm and 0.45 mm. A pickup success rate of 95% or more was evaluated as good (O), and a case of less than 95% was evaluated as poor (X).

Reliability evaluation: A package was produced together with a silicon wafer, left for 168 hours under conditions of temperature and humidity of 85°C/85%, and then subjected to a high temperature reflow process of 260°C three times. At this time, when the amount of voids (black areas) measured in the SAT transmission mode was 5% or less, it was evaluated as good (O), and when it exceeded 5%, it was evaluated as bad (X).

Referring to Table 2 above, the glass transition temperature of the first film is 130 ° C. or higher, and the value of (thermal expansion coefficient/storage modulus) of the spacer film is 1 ppm/GPa to 15 ppm/GPa. In the case of 5, there were no defects in chip recognition, pick-up performance and reliability. On the other hand, in the case of Comparative Examples 1 to 3 in which the value of (thermal expansion coefficient/storage modulus) is more than 15 ppm/GPa or less than 1 ppm/GPa, at a needle pin height of 0.45 mm of the pickup device, Poor chip recognition, poor pick-up and poor reliability were confirmed. Even if the value of (thermal expansion coefficient/storage modulus) satisfies 1 ppm/GPa to 15 ppm/GPa, in the case of Comparative Example 4 in which the glass transition temperature is less than 130° C., chip recognition and pick-up performance are poor. No, but there was a lack of reliability.

Therefore, adjusting the thermal expansion coefficient and storage elastic modulus of the spacer film to maintain the value of (thermal expansion coefficient/storage elastic modulus) at 1 to 15 ppm/GPa is essential for chip recognition and pick-up. It can be confirmed that the glass transition temperature of the first film is 130° C. or higher, the reliability is also satisfied at the same time, and it can be confirmed that it is suitable for use as a spacer film.

Although the present invention has been described above, it should be understood that the present invention is not limited by the embodiments disclosed herein, and that various modifications can be made by those skilled in the art within the scope of the technical idea of the present invention. Self-explanatory. At the same time, even if the working effects of the configuration of the present invention are not explicitly described and explained while the embodiments of the present invention are described above, it should be understood that the predictable effects of the configuration must also be recognized. is.

110: Package substrate 120: First semiconductor chip unit 130: Spacer 131: Adhesive layer 132: Support 140: Second semiconductor chip unit 150: Package body 510: First film 520: Adhesive layer 530: Second film 535: First Pressure sensitive adhesive layer 540: Cover film 545: Second reduced pressure adhesive layer 601: Dicing saw 610: Frame 620: Push means 630: Adsorption means

Claims (17)

A first film having a glass transition temperature (Tg) of 130° C. or higher;
and an adhesive layer disposed under the first film,
A spacer film that satisfies Equation 1 below.
[Formula 1]
1 ppm/GPa ≤ (thermal expansion coefficient/storage modulus) ≤ 15 ppm/GPa
(In Equation 1, the coefficient of thermal expansion and the storage modulus are values measured at 25°C.) 2. The spacer film according to claim 1, wherein said thermal expansion coefficient is 10 ppm to 50 ppm. 2. The spacer film according to claim 1, wherein said storage modulus is 2 GPa to 10 GPa. The spacer film according to claim 1, wherein the first film includes at least one of polyimide, polyetheretherketone, polyamideimide, polyphenylene sulfide, polyphthalamide, polysulfone, polyethersulfone and polyetherimide. . 2. The spacer film according to claim 1, wherein said first film includes a coating layer on said lower portion. 6. The coating layer of claim 5, wherein the coating layer comprises at least one of a compound containing polyimide functional groups, a compound containing polyamideimide functional groups, a compound containing epoxy functional groups, and a compound containing urethane acrylate functional groups. Spacer film. 2. The spacer film according to claim 1, wherein the adhesive layer contains at least one of an acrylic compound and an epoxy resin. The spacer film of claim 1, further comprising a first pressure-sensitive adhesive layer disposed under the adhesive layer. 9. The spacer film according to claim 8, wherein said first pressure-sensitive adhesive layer comprises an acrylic compound. 9. The spacer film of claim 8, wherein the edge of the top surface of the first pressure sensitive adhesive layer is exposed. The attachment force between the first pressure-sensitive adhesive layer and the adhesive layer is 20 to 200 N/m before UV curing of the first pressure-sensitive adhesive layer, and UV curing of the first pressure-sensitive adhesive layer. 9. The spacer film according to claim 8, wherein the rest is 15 N/m or less. 9. The spacer film of claim 8, further comprising a second film disposed under the first pressure-sensitive adhesive layer. 13. The spacer film according to claim 12, wherein the second film contains a polyolefin resin. a second pressure-sensitive adhesive layer disposed on top of the first film;
The spacer film according to claim 1, further comprising a cover film disposed on top of the second pressure-sensitive adhesive layer. A fixing step of fixing the spacer film according to claim 1 to a frame;
a dicing step of dicing the spacer film into individual pieces;
a pick-up step of picking up spacers composed of the first film and the adhesive layer from the singulated result;
a mounting step of mounting the picked-up spacer onto a package substrate. the spacer film further comprising a first pressure-sensitive adhesive layer disposed under the adhesive layer;
an edge of the top surface of the first pressure-sensitive adhesive layer is exposed;
16. The method of forming a spacer of claim 15, wherein said frame is positioned on said edge of said top surface of said first pressure sensitive adhesive layer. a package substrate;
a spacer comprising the spacer film according to claim 1 arranged on the package substrate;
a first semiconductor chip unit arranged on the package substrate;
a second semiconductor chip unit stacked on the spacer and the first semiconductor chip unit;
wires electrically connecting the chip pads of the first semiconductor chip unit and the corresponding first substrate pads, and the chip pads of the second semiconductor chip unit and the corresponding second substrate pads;
A multi-chip package including a package body sealing the first semiconductor chip unit, the second semiconductor chip unit, the wires and the spacer.

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