JP2022111042A - Semiconductor device and method of manufacturing semiconductor device - Google Patents

Abstract

To provide a semiconductor device and a method of manufacturing the semiconductor device capable of comparatively suppressing adhesion unevenness in attaching a plurality of semiconductor chips to a substrate in a state interposing an adhesion sheet.SOLUTION: A method of manufacturing a semiconductor device implements a semiconductor chip attaching step for sequentially pressing a plurality of semiconductor chips by a first pressing member so as to adhere them to a plurality of mounting areas by using a plurality of semiconductor chips B1 and B2, a lead frame substrate D having a plurality of mounting areas on which the plurality of semiconductor chips are mounted, a plurality of adhesion sheets 2 containing sinterable metal particles which can be sintered by heating to a temperature not higher than 400°C, and the first pressing member (collet A) which presses the semiconductor chips to the substrate in a state interposing the adhesion sheet so as to adhere the plurality of semiconductor chips to the plurality of mounting areas. In the semiconductor chip attaching step, the pressing of the semiconductor chips is implemented by using the first pressing member heated to a temperature at which the sinterable metal particles can be sintered.SELECTED DRAWING: Figure 5

Description

The present invention relates to a semiconductor device and a method for manufacturing a semiconductor device.

Conventionally, in the manufacture of semiconductor devices, a method of bonding a semiconductor chip (hereinafter also referred to as a die) to a substrate (lead frame substrate, etc.) with a film containing sinterable particles interposed therebetween is known (for example, , the following patent document 1).

Patent Document 1 below describes forming a dry film (hereinafter also referred to as a sheet) using a paste composition containing sinterable particles, and bonding the die to the substrate through the film. It is
Further, in Patent Document 1 below, after disposing at least one die on the substrate with the film interposed therebetween to form an assembly, a pressure of less than 40 MPa is applied to the assembly, and It describes applying a temperature of 175° C. to 400° C. to the substrate and mounting at least one die on the substrate.

Japanese Patent Application Publication No. 2014-503936

By the way, according to the method described in Patent Document 1, when the plurality of semiconductor chips are attached to the substrate at once by pressing while heating with a sheet containing sinterable particles interposed therebetween, the substrate The bonding state of the plurality of semiconductor chips may be uneven (bonding unevenness may occur).
However, in attaching the plurality of semiconductor chips to the substrate with the sheet (adhesive sheet) interposed therebetween, it is difficult to say that sufficient studies have been made to suppress uneven adhesion.

Accordingly, the present invention provides a method for manufacturing a semiconductor device capable of relatively suppressing uneven adhesion in attaching a plurality of semiconductor chips to a substrate with an adhesive sheet interposed therebetween, and a semiconductor device manufactured by the method. An object is to provide a semiconductor device.

A method for manufacturing a semiconductor device according to the present invention includes:
a plurality of semiconductor chips;
a substrate having a plurality of mounting areas on which the plurality of semiconductor chips are mounted;
a plurality of adhesive sheets containing sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less;
a first pressing member that presses the semiconductor chip toward the substrate with the adhesive sheet interposed therebetween to bond the plurality of semiconductor chips to the plurality of mounting regions;
performing a semiconductor chip mounting step of sequentially pressing the plurality of semiconductor chips with the first pressing member to bond them to the plurality of mounting regions;
In the semiconductor chip mounting step, the semiconductor chip is pressed using the first pressing member heated to a temperature at which the sinterable metal particles can be sintered.

According to such a configuration, in the semiconductor chip mounting step, the plurality of semiconductor chips are sequentially pressed by the first pressing member to adhere to the plurality of mounting regions, and in addition, the sinterable metal particles Since the semiconductor chips are pressed using the first pressing member heated to a temperature at which the semiconductor chips can be sintered, the plurality of semiconductor chips are compared one by one with the adhesive sheet interposed therebetween. can be attached to the mounting area in a substantially uniform manner.
As a result, when a plurality of semiconductor chips are attached to a substrate with an adhesive sheet interposed therebetween, uneven adhesion can be relatively suppressed.

Further, in the method for manufacturing the semiconductor device,
After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
Preferably, in the secondary heating step, the heating is performed without pressing part or all of the plurality of semiconductor chips toward the substrate.

According to such a configuration, some or all of the plurality of semiconductor chips can be more firmly attached to the substrate with the adhesive sheet interposed therebetween.
That is, it is possible to improve connection reliability of some or all of the plurality of semiconductor chips to the substrate.
Further, the equipment used in the second heating step can be made simple without a pressing member for pressing a part or all of the plurality of semiconductor chips.

Further, in the method for manufacturing the semiconductor device,
Preferably, in the secondary heating step, the heating is performed without pressing all of the plurality of semiconductor chips toward the substrate.

According to such a configuration, all of the plurality of semiconductor chips can be attached more firmly to the substrate with the adhesive sheet interposed therebetween.
That is, it is possible to improve the connection reliability of all of the plurality of semiconductor chips to the substrate.

Further, in the method for manufacturing the semiconductor device,
After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
Preferably, in the secondary heating step, the heating is performed while pressing some or all of the plurality of semiconductor chips toward the substrate.

According to this configuration, in the secondary heating step, the heating is performed while pressing some or all of the plurality of semiconductor chips toward the substrate. can be more firmly attached to the substrate with an adhesive sheet interposed therebetween.
That is, it is possible to further improve the connection reliability of some or all of the plurality of semiconductor chips to the substrate.

Further, in the method for manufacturing the semiconductor device,
Preferably, in the secondary heating step, the heating is performed while pressing all of the plurality of semiconductor chips toward the substrate.

According to such a configuration, all of the plurality of semiconductor chips can be more firmly attached to the substrate with the adhesive sheet interposed therebetween.
That is, it is possible to further improve the connection reliability of all of the plurality of semiconductor chips to the substrate.

Further, in the method for manufacturing the semiconductor device,
Preferably, in the semiconductor chip mounting step, the first pressing member is heated to a temperature of 250° C. or higher.

According to such a configuration, each of the plurality of semiconductor chips can be attached more firmly to the substrate with the adhesive sheet interposed therebetween.
That is, it is possible to improve connection reliability of each of the plurality of semiconductor chips to the substrate.

A semiconductor device according to the present invention includes:
A semiconductor device manufactured by the method for manufacturing a semiconductor device according to any one of the above,
A shear strength at 25° C. between one semiconductor chip of the plurality of semiconductor chips and the mounting region is 2 MPa or more.

According to such a configuration, the semiconductor device has improved connection reliability of each of the plurality of semiconductor chips to the substrate.

According to the present invention, there is provided a method for manufacturing a semiconductor device capable of relatively suppressing uneven adhesion in attaching a plurality of semiconductor chips to a substrate with an adhesive sheet interposed therebetween, and a semiconductor device manufactured by the method. A semiconductor device can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic sectional drawing which shows the structure of the laminated body which concerns on one Embodiment of this invention. 4A is a schematic cross-sectional view showing how the collet lifts the first semiconductor chip from the dicing tape; FIG. 4B is a schematic cross-sectional view showing how the collet lifts the second semiconductor chip from the dicing tape; FIG. 4A is a schematic cross-sectional view showing how a part of the adhesive sheet of the laminate is transferred to the first semiconductor chip; FIG. 4B is a schematic cross-sectional view showing how a part of the adhesive sheet of the laminate is transferred to the second semiconductor chip; FIG. 4A is a schematic cross-sectional view showing how the collet lifts the first semiconductor chip with the adhesive sheet from the laminate; FIG. 4B is a schematic cross-sectional view showing how the collet lifts the second semiconductor chip with the adhesive sheet from the laminate; FIG. 4A is a schematic cross-sectional view showing how a first semiconductor chip with an adhesive sheet is attached to a first die pad of a lead frame; FIG. 4B is a schematic cross-sectional view showing how a second semiconductor chip with an adhesive sheet is attached to a second die pad of a lead frame; FIG. (a) is a schematic sectional drawing which shows an example of a secondary heating process. (b) is a schematic cross-sectional view showing another example of the secondary heating process.

An embodiment of the present invention will be described below.

[Adhesive sheet]
Before describing the method for manufacturing a semiconductor device according to this embodiment, first, an adhesive sheet used in the method for manufacturing a semiconductor device according to this embodiment will be described.

One side and the other side of the adhesive sheet are adhesive surfaces to be adhered to adherends, respectively.
The adhesive sheet contains sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less.
In this way, since the adhesive sheet contains the sinterable metal particles as described above, when the adhesive sheet is heated at a temperature at which the sinterable metal particles can be sintered, the sinterable metal particles can be sintered. A bonding layer is formed to ensure adhesion to the adherend on one side and adhesion to the adherend on the other side.
Further, by forming the sintered layer, the adherend adhered to one surface side of the adhesive sheet and the adherend adhered to the other surface side of the adhesive sheet are electrically connected. .
In the present specification, sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less mean that necking is observed on the outer surfaces of the particles when heated at a temperature of 400° C. or less. means something
The sintering temperature of the sinterable metal particles can be measured using a thermogravimetric differential thermal analyzer.
Specifically, a thermogravimetric differential thermal analyzer (for example, a differential thermal balance TG8120 manufactured by Rigaku) is used for measurement under the following conditions to obtain a Tg curve and a DTA curve, and a Tg curve can be obtained by obtaining the temperature of the largest peak of the DTA curve observed near the falling edge of .

<Measurement conditions>
・Temperature increase rate: 10°C/min
・Measurement atmosphere: Air ・Measurement temperature range: Room temperature (23±2°C) to 500°C

Sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less include particles of gold, silver, copper, palladium, tin, nickel, and alloys thereof.
Moreover, a metal oxide is also mentioned as said sinterable metal particle. Examples of the metal oxide include silver oxide, copper oxide, palladium oxide and tin oxide.
The sinterable metal particles may be particles having a core-shell structure. Examples of the particles having a core-shell structure include particles containing a core made of copper and a shell covering the core and made of gold, silver, or the like.
The sinterable metal particles are selected from the group consisting of silver, copper, silver oxide, and copper oxide from the viewpoint that the adhesive sheet can become a sintered layer that is firmly adhered to the adherend after sintering. It preferably contains at least one particle that is
Furthermore, from the viewpoint that the adhesive sheet can be excellent in electrical conductivity and thermal conductivity after sintering, the sinterable metal particles are at least one particle selected from the group consisting of silver and copper. preferably contains
Moreover, from the viewpoint of improving oxidation resistance, the sinterable metal particles preferably contain silver particles. Since the sinterable metal particles contain silver particles, oxidation of the sinterable metal particles can be suppressed when the sinterable metal particles are sintered in an air atmosphere. .
Furthermore, particles containing a core made of copper and a shell made of silver covering the core (hereinafter also referred to as silver-coated copper particles), and a combination of silver particles, the sinterable metal particles may be
The sinterable metal particles are contained in the adhesive sheet in the form of either primary particles or secondary particles in which the primary particles are aggregated.

The sinterable metal particles preferably have a volume average particle diameter _D50 of 0.01 μm or more, more preferably 0.1 μm or more.
The sinterable metal particles preferably have a volume average particle diameter _D50 of 10 μm or less, more preferably 5 μm or less, and particularly preferably 1 μm or less.
When the sinterable metal particles are composed of two or more types of particles, the volume average particle diameter _D50 means a value measured in a state in which two or more types of particles are mixed.

The volume average particle diameters _D50 and _D90 of the sinterable metal particles are measured on a volume basis using, for example, a laser diffraction/scattering flow particle size analyzer (Microtrac MT3000II series manufactured by Microtrac Bell). can be measured.

The adhesive sheet contains a binder in addition to sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less.
The adhesive sheet may contain a plasticizer and the like in addition to the sinterable metal particles and binder.
The binder includes a polymer binder and a binder other than polymer (hereinafter also referred to as a low-molecular-weight binder).

The polymeric binder is preferably a thermally decomposable polymeric binder.
The thermally decomposable polymer binder is a binder thermally decomposed at a temperature at which the sinterable metal particles can be sintered.
Further, the thermally decomposable polymer binder retains the shape of the adhesive sheet until the sinterable metal particles are sintered.
In the present embodiment, the thermally decomposable polymer binder is preferably solid at room temperature (23±2° C.) from the viewpoint that the shape of the adhesive sheet can be easily maintained. Examples of such thermally decomposable polymer binders include polycarbonate resins and acrylic resins.

Examples of the polycarbonate resins include aliphatic polycarbonates and aromatic polycarbonates.
The aromatic polycarbonate contains benzene rings between carbonate ester groups (--O--CO--O--) in the main chain.
The aliphatic polycarbonate contains an aliphatic chain without a benzene ring between the main chain carbonate groups (--O--CO--O--).
Examples of the aliphatic polycarbonate include polyethylene carbonate and polypropylene carbonate.
Examples of the aromatic polycarbonates include polycarbonates containing a bisphenol A structure in the main chain.

The acrylic resin contains a (meth)acrylic acid ester as a structural unit.
Examples of the (meth)acrylic acid esters include (meth)acrylic acid esters having a linear or branched alkyl group having 4 to 18 carbon atoms.
Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, heptyl group, cyclohexyl group, 2- Examples include ethylhexyl, octyl, isooctyl, nonyl, isononyl, decyl, isodecyl, undecyl, lauryl, tridecyl, tetradecyl, stearyl and octadecyl groups.

The acrylic resin may contain a monomer other than the (meth)acrylic acid ester as a structural unit.
Examples of monomers other than (meth)acrylic acid esters include carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and the like.

Examples of the carboxy group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid.
Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride.
Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, 4-(hydroxymethyl)cyclohexylmethyl (meth)acrylate and the like.
Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, (meth) ) acryloyloxynaphthalenesulfonic acid and the like.
Examples of the phosphoric acid group-containing monomer include 2-hydroxyethyl acryloyl phosphate.

In addition, in this specification, "(meth)acryl" is a concept including acryl and methacryl.
Moreover, "(meth)acrylate" is a concept including acrylate and methacrylate.

The weight average molecular weight of the polymeric binder is preferably 10,000 or more.
In addition, a mass average molecular weight means what was measured by a gel permeation chromatography (GPC) and converted into polystyrene.
For example, the mass average molecular weight is measured by using Tosoh's GPC "HLC-8320GPC" as an apparatus, Tosoh's column "TSK guardcolumn H _HR (S)" and Tosoh's column "TSK GMH _HR -H. (S)” and a column “TSK GMH _HR -H(S)” manufactured by Tosoh Corporation are connected in series, and “TSK gel SuperH-RC” is used as a reference column. , using tetrahydrofuran (THF) as an eluent, a column temperature of 40 ° C., a flow rate of 0.5 mL / min calculated from the results of GPC measurement, it can be obtained as a value in terms of polystyrene.

The low-molecular-weight binder preferably contains a low-boiling-point binder having a boiling point lower than the thermal decomposition initiation temperature of the thermally decomposable polymer binder.
Also, the low molecular weight binder is preferably liquid at 23°C.
Further, the low-molecular-weight binder preferably exhibits a viscosity of 1×10 ⁵ Pa·s or less at 23°C.
The viscosity can be measured with a dynamic viscoelasticity measuring device (trade name “HAAKE MARS III”, manufactured by Thermo Fisher Scientific). In this measurement, parallel plates of 20 mmφ are used as jigs, the gap between the plates is 100 μm, and the shear rate in rotational shear is 1 s ⁻¹ .

Examples of the low-molecular-weight binder include alcohols and ethers.
Terpene alcohols are mentioned as said alcohol.
Examples of the terpene alcohols include isobornylcyclohexanol, citronellol, geraniol, nerol, carveol and α-terpionol.
Examples of alcohols other than terpene alcohols include pentanol, hexanol, heptanol, octanol, 1-decanol, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, and 2,4-diethyl-1,5- Pentanediol may be mentioned.
Examples of the ethers include alkylene glycol alkyl ethers.
Examples of the alkylene glycol alkyl ethers include ethylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, diethylene glycol isobutyl ether, diethylene glycol hexyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, and diethylene glycol butyl. methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, propylene glycol propyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, di Propylene glycol butyl ether, dipropylene glycol dimethyl ether, tripropylene glycol methyl ether, tripropylene glycol dimethyl ether and the like.
Examples of ethers other than the alkylene glycol alkyl ethers include ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate, and dipropylene glycol methyl ether acetate.

The low-molecular-weight binder is preferably a terpene alcohol, more preferably isobornylcyclohexanol.
Here, isobornylcyclohexanol is an organic compound having a boiling point of 308 to 318° C., and the temperature is raised from room temperature to 600° C. at a temperature elevation of 10° C./min under a nitrogen gas stream of 200 mL/min. At 100 ° C. or higher, the mass is greatly reduced, and at 245 ° C., it evaporates and disappears (no further mass loss is observed).
As described above, isobornylcyclohexanol exhibits an extremely high viscosity at 25° C., so that when contained in the adhesive sheet, it can maintain the sheet shape at room temperature.
Further, in the present embodiment, the sinterable metal particles contained in the adhesive sheet are metal particles that can be sintered by heating at a temperature of 400° C. or less, and such sinterable metal particles are usually , and sintered at a temperature of about 200 to 300°C. That is, a temperature of 200 to 300° C. is adopted as the sintering temperature.
Therefore, when isobornylcyclohexanol is contained in the adhesive sheet, the isobornylcyclohexanol volatilizes out of the adhesive sheet during sintering when the sintering temperature as described above is employed. As a result, the sinterable metal particles have a close positional relationship in the adhesive sheet. Thereby, in the adhesive sheet, the sintering of the sinterable metal particles can be further promoted.
The above mass reduction is a value when the mass reduction rate at the measurement start temperature (room temperature) is assumed to be 0%.

The content ratio (particle filling rate) of the sinterable metal particles in the adhesive sheet is preferably 85% by mass or more and 97% by mass or less, more preferably 88% by mass or more and 96% by mass or less.
When the adhesive sheet contains the sinterable metal particles in an amount of 85% by mass or more, it becomes easy to exhibit sufficient conductivity after sintering.
Further, when the adhesive sheet contains 97% by mass or less of the sinterable metal particles, the shape of the adhesive sheet is easily maintained.
The content ratio of the sinterable metal particles in the adhesive sheet is the content ratio before sintering the sinterable metal particles.

The content of the polymer binder in the adhesive sheet is preferably 0.1% by mass or more and 10% by mass or less, and more preferably 0.5% by mass or more and 5% by mass or less.
When the adhesive sheet contains 0.1% by mass or more of the polymer binder, the shape of the adhesive sheet is easily maintained.
In addition, since the front adhesive sheet contains 10% by mass or less of the polymer binder, residual components derived from the polymer binder can be reduced after sintering.

The content of the low-molecular-weight binder in the adhesive sheet is preferably 1% by mass or more and 20% by mass or less, and more preferably 2% by mass or more and 15% by mass or less.
When the adhesive sheet contains 1% by mass or more of the low-molecular-weight binder, the adhesive sheet has excellent transferability to the adherend.
In addition, when the adhesive sheet contains 20% by mass or less of the low-molecular-weight binder, residual components derived from the low-molecular-weight binder can be reduced after sintering.

The thickness of the adhesive sheet is preferably 5 μm or more, more preferably 10 μm or more.
Moreover, the thickness of the adhesive sheet is preferably 300 μm or less, more preferably 150 μm or less.
The thickness of the adhesive sheet can be obtained by, for example, using a dial gauge (PEACOCK, model R-205) to measure the thickness at five randomly selected points and averaging these thicknesses. can be done.

As shown in FIG. 1, the adhesive sheet 2 configured as described above is used in the manufacture of a semiconductor device in the state of a laminated body 10 laminated on the base sheet 1. As shown in FIG.
In the laminate 10, the adhesive sheet 2 is laminated on the base sheet 1 in a detachable manner.

The base sheet 1 is a resin layer containing resin.
Examples of the resin contained in the resin layer include polyolefin resin, polyester resin, polyurethane resin, polycarbonate resin, polyetheretherketone resin, polyimide resin, polyetherimide resin, polyamide resin, polyvinyl chloride resin, polyvinylidene chloride resin, poly Phenyl sulfide resins, fluororesins, cellulose resins, silicone resins and the like can be mentioned.

The thickness of the base sheet 1 is preferably 10 μm or more and 5000 μm or less, more preferably 20 μm or more and 4000 μm or less, and even more preferably 30 μm or more and 3000 μm or less.
The thickness of the base sheet 1 is obtained by, for example, using a dial gauge (PEACOCK, model R-205) to measure the thickness at five randomly selected points and averaging these thicknesses. be able to.

[Method for manufacturing a semiconductor device]
A method for manufacturing a semiconductor device according to an embodiment of the present invention (hereinafter also referred to as this embodiment) comprises:
a plurality of semiconductor chips;
a substrate having a plurality of mounting areas on which the plurality of semiconductor chips are mounted;
a plurality of adhesive sheets containing sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less;
a first pressing member that presses the semiconductor chip toward the substrate with the adhesive sheet interposed therebetween to bond the plurality of semiconductor chips to the plurality of mounting regions;
A semiconductor chip attaching step is performed in which the plurality of semiconductor chips are pressed in order by the first pressing member to adhere to the plurality of mounting regions.
In the method of manufacturing a semiconductor device according to the present embodiment, in the semiconductor chip mounting step, the semiconductor chip is mounted using the first pressing member heated to a temperature at which the sinterable metal particles can be sintered. Pressing is performed.

An example of a method for manufacturing a semiconductor device using the laminate 10 will be described below with reference to FIGS.
In the following description, the substrate is a lead frame substrate, the mounting area is a die pad, and the first pressing member is a collet.

First, a plurality of semiconductor chips are obtained by cutting a semiconductor wafer on a dicing tape.
Next, as shown in FIG. 2A, one semiconductor chip B1 (hereinafter also referred to as first semiconductor chip B1) among the plurality of semiconductor chips is lifted from the dicing tape C by the collet A. As shown in FIG.
In addition, the semiconductor chip usually has a rectangular shape in plan view, and more specifically, has a square shape in plan view.
Also, the thickness of the semiconductor chip is, for example, 10 μm or more and 500 μm or less, more specifically, 20 μm or more and 400 μm or less.
In addition, the area of the semiconductor chip in plan view is, for example, 0.01 mm ² or more and 1000 mm ² or less, more specifically 0.04 mm ² or more and 500 mm ² or less.
Furthermore, the dimension of the collet A on the side that abuts the semiconductor chip is a size corresponding to the chip size. That is, the area S1 (hereinafter also referred to as collet area S1) of the surface of the collet A in contact with the semiconductor chip in plan view corresponds to the area S2 (hereinafter also referred to as chip area S2) of the semiconductor chip in plan view. is. More specifically, the collet area S1 is 0.9 to 1.1 times as large as the chip area S2.

Next, as shown in FIG. 3A, the laminate 10 is placed on the stage G so that the adhesive sheet 2 of the laminate 10 faces upward.
Then, by pressing the first semiconductor chip B1 against the adhesive sheet 2 of the laminate 10 with the collet A, a part of the adhesive sheet 2 is transferred to the first semiconductor chip B1. As a result, the first semiconductor chip B1 with the adhesive sheet 2 is obtained.
The pressure for pressing the first semiconductor chip B1 against the adhesive sheet 2 is preferably 0.01 MPa or more and 10 MPa or less, and more preferably 0.1 MPa or more and 5 MPa or less.
The temperature of the collet A or the stage G when pressing the first semiconductor chip B1 against the adhesive sheet 2 is preferably 40° C. or higher and 150° C. or lower, and more preferably 50° C. or higher and 120° C. or lower.

Next, as shown in FIG. 4A, the collet A lifts the first semiconductor chip B1 with the adhesive sheet 2 from the laminate 10. Then, as shown in FIG.

Next, the lead frame substrate D is placed on the stage H as shown in FIG. 5(a).
Next, while the collet A is held at any temperature within the range of 25° C. or higher and 100° C. or lower, the collet A is vertically lowered to remove the first semiconductor chip B1 with the adhesive sheet 2 from the adhesive sheet 2. It is brought into contact with one die pad E1 (first die pad E1) on the lead frame substrate D from the side.
Next, while the adhesive sheet of the first semiconductor chip B1 with the adhesive sheet 2 is in contact with the first die pad E1 of the lead frame substrate D, the first semiconductor chip B1 with the adhesive sheet 2 is pressed with the collet A. By heating the collet A to a temperature at which the sinterable metal particles (the sinterable metal particles contained in the adhesive sheet 2) can be sintered (while pressing), the sinterable metal particles in the adhesive sheet 2 are The metal particles are primarily sintered (see FIG. 5(a)).
The pressure when the first semiconductor chip B1 with the adhesive sheet 2 is pressed against the first die pad E1 of the lead frame substrate D from the side of the adhesive sheet 2 is preferably 0.01 MPa or more and 50 MPa or less, more preferably 0.1 MPa or more and 30 MPa or less. is more preferable.
Collet A is preferably heated to a temperature of 250° C. or higher. By heating the collet A to a temperature of 250° C. or higher, the sinterable metal particles can be more sufficiently sintered, so that the semiconductor chip can be firmly attached to the substrate with the adhesive sheet interposed therebetween. can be attached to That is, it is possible to improve connection reliability of the semiconductor chip to the substrate.
Moreover, it is preferable that the collet A be rapidly heated (in about 5 seconds) to a temperature at which the sinterable metal particles can be sintered.
The collet A is preferably heated at 30° C./sec or more, more preferably 45° C./sec or more, to a temperature at which the sinterable metal particles can be sintered.
In addition to the collet A, the primary sintering may be performed by heating the stage H to a temperature higher than the temperature at which the sinterable metal particles can be sintered. As a result, since the adhesive sheet 2 can be heated from both sides, the sinterable metal particles can be more sufficiently sintered. As a result, the semiconductor chip can be more firmly attached to the substrate with the adhesive sheet interposed therebetween. That is, it is possible to further improve the connection reliability of the semiconductor chip to the substrate.
Moreover, the temperature for heating the stage H is preferably lower than or equal to the temperature at which the lead frame substrate D is prevented from being oxidized. For example, when the lead frame substrate D is made of a Cu alloy (Cu--Cr--Zr, Cu--Cr--Sn--Zn, Cu--Ni--Si--Mg, etc.), the temperature for heating the stage H is It is preferably 150° C. or less.

After the sinterable metal particles are primarily sintered, the collet A is lifted to separate from the first semiconductor chip B1 with the adhesive sheet 2, and the temperature of the collet A is adjusted so that the sinterable metal particles are sintered. The temperature is lowered to a temperature (eg, 50° C.) at which it becomes difficult to bond.

After the temperature of the collet A is lowered as described above, as shown in FIG. ) is lifted from the dicing tape C.
Next, as shown in FIG. 3B, by pressing the second semiconductor chip B2 against the adhesive sheet 2 of the laminate 10 with the collet A, a part of the adhesive sheet 2 is transferred to the second semiconductor chip B2. . As a result, the second semiconductor chip B2 with the adhesive sheet 2 is obtained.
Next, as shown in FIG. 4B, the collet A lifts the second semiconductor chip B2 with the adhesive sheet 2 from the dicing tape C. Then, as shown in FIG.
Next, while the collet A is held at any temperature within the range of 25° C. or higher and 100° C. or lower, the second semiconductor chip B2 with the adhesive sheet 2 is attached to another die pad on the lead frame substrate D from the adhesive sheet 2 side. It is brought into contact with E2 (second die pad E2).
Next, while the adhesive sheet of the second semiconductor chip B2 with the adhesive sheet 2 is in contact with the second die pad E2 of the lead frame substrate D, the second semiconductor chip B2 with the adhesive sheet 2 is pressed with the collet A. (While pressing), the sinterable metal particles contained in the adhesive sheet 2 are primarily sintered (see FIG. 5(b)).
The heating temperature of the collet A and the pressure when the first semiconductor chip B1 with the adhesive sheet 2 is pressed against the die pad E2 of the lead frame substrate D from the side of the adhesive sheet 2 are selected as described above.
After primary sintering of the sinterable metal particles, the collet A is lifted up to separate the collet A from the second semiconductor chip B2 with the adhesive sheet 2, and the temperature of the collet A is reduced to that of the sinterable metal particles. Lower the temperature to a point where the particles no longer sinter (eg, 50° C.).
The above steps are repeated until all the die pads of the lead frame substrate D are attached with semiconductor chips.
Thus, the semiconductor chip mounting process is performed.
After the semiconductor chips have been attached to all the die pads of the lead frame substrate D (after the semiconductor chip attachment step), bonding wires may be bonded to the necessary locations.

In the method of manufacturing a semiconductor device according to the present embodiment, as described above, a plurality of semiconductor chips are sequentially pressed by the first pressing member (collet A) to form a plurality of substrates (lead frame substrate D). In addition to bonding to the mounting area (first die pad E1, second die pad E2), the first pressing member (collet) heated to a temperature at which the sinterable metal particles contained in the adhesive sheet 2 can be sintered. A) is used to press the semiconductor chips (first semiconductor chip B1, second semiconductor chip B2).
Therefore, with the adhesive sheet 2 interposed, each of the plurality of semiconductor chips (the first semiconductor chip B1 and the second semiconductor chip B2) is relatively evenly distributed over the mounting area (the second semiconductor chip) of the substrate (lead frame substrate D). 1 die pad E1, second die pad E2).
As a result, when the plurality of semiconductor chips (the first semiconductor chip B1 and the second semiconductor chip B2) are attached to the substrate (the lead frame substrate D) with the adhesive sheet 2 interposed, uneven adhesion is relatively suppressed. be able to.

Further, in the method for manufacturing a semiconductor device according to this embodiment,
After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
Preferably, in the secondary heating step, the heating is performed without pressing part or all of the plurality of semiconductor chips toward the substrate.
Furthermore, in the method for manufacturing a semiconductor device according to this embodiment,
Preferably, in the secondary heating step, the heating is performed without pressing all of the plurality of semiconductor chips toward the substrate.

More specifically, after the semiconductor chips have been attached to all the die pads of the lead frame substrate D (after the semiconductor chip attachment process), all the lead frame substrates D have a die pad as shown in FIG. A temperature at which the sinterable metal particles contained in the adhesive sheet 2 can be sintered (for example, in the range of 200° C. or higher and 400° C. or lower) without pressing part or all of the semiconductor chip attached to the die pad. Any temperature) may be heated (secondary heating process may be performed).
In FIG. 6A, all the semiconductor chips (first semiconductor chip B1 and second semiconductor chip B2) to which all the die pads (first die pad E1 and second die pad E2) of the lead frame substrate D are attached are removed. An example of heating without pressing is shown.
By performing such a secondary heating step, the sinterable metal particles can be further sintered (secondary sintering can be performed), so that the semiconductor chip can be placed with the adhesive sheet interposed. It can be more firmly attached to the substrate (lead frame substrate D) in the state of being held. That is, the connection reliability of the semiconductor chip to the substrate can be improved.
Also, the equipment used in the secondary heating process can be made simple without a pressing member for pressing a part or all of the plurality of semiconductor chips.
Even when such a secondary heating process is performed, bonding wires may be bonded to necessary locations after the secondary heating process.

Further, in the method for manufacturing a semiconductor device according to this embodiment,
After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
In the secondary heating step, the heating may be performed while pressing some or all of the plurality of semiconductor chips toward the substrate.
Furthermore, in the method for manufacturing a semiconductor device according to this embodiment,
In the secondary heating step, the heating may be performed while pressing all of the plurality of semiconductor chips toward the substrate.

More specifically, after the semiconductor chips have been attached to all the die pads of the lead frame substrate D (after the semiconductor chip attachment step), all the lead frame substrates D have a die pad as shown in FIG. 6(b). Using a heating and pressurizing device F which has two flat plates (parallel plates) arranged so as to sandwich a part or all of the semiconductor chip attached to the die pad from above and below and is configured to be heatable, Some or all of the semiconductor chips attached to all the die pads of the lead frame substrate D may be heated at a sinterable temperature while applying pressure (a secondary heating step may be performed). .
In FIG. 6B, all of the semiconductor chips (first semiconductor chip B1 and second semiconductor chip B2) attached to all die pads (first die pad E1 and second die pad E2) of lead frame substrate D are An example of heating while pressing is shown.
By carrying out such a secondary heating process, it is possible to perform heating while pressing some or all of the plurality of semiconductor chips toward the substrate (lead frame substrate D). Some or all of them can be more firmly attached to the substrate (lead frame substrate D) with the adhesive sheet 2 interposed therebetween. That is, the connection reliability of the semiconductor chip to the substrate can be further improved.
Even when such a secondary heating process is performed, bonding wires may be bonded to necessary locations after the secondary heating process.

As the lead frame substrate D, various known lead frame substrates can be used. Examples of various known lead frame substrates include a lead frame substrate obtained by plating a Cu lead frame substrate with Ag, and a lead frame substrate obtained by plating a Cu lead frame substrate with Ni, Pd, and Au in this order (Palladium Prefabricated). Plated Lead Frame, Pd-PPF) and the like.

[Semiconductor device]
The semiconductor device according to this embodiment is a semiconductor device manufactured by the method for manufacturing a semiconductor device according to this embodiment.
Further, in the semiconductor device according to the present embodiment, the shear strength at 25° C. between one semiconductor chip of the plurality of semiconductor chips and the substrate is 2 MPa or more.
Since the shear strength at 25° C. is 2 MPa or more, the semiconductor device according to this embodiment has improved connection reliability of the semiconductor chip to the substrate.
The shear strength at 25° C. may be 200 MPa or less.

The shear strength at 25°C can be measured as follows.
Specifically, a test body in which a bare chip with an adhesive sheet is attached to the die pad of the lead frame substrate is obtained, and the test body is tested using a universal bond tester series 4000 manufactured by Nordson Advanced Technologies, Inc. as follows: The shear strength at 25°C is measured by adopting the conditions shown.

<Shear strength measurement conditions>
・Load cell: DS100kg
・Measurement range: 100 kg
・Test type: Destructive test ・Test speed: 100 μm/s
・Descent speed: 100 μm/s
・Test height: 100 μm
・Tool movement amount: 2000 μm
・ Destruction recognition point: low (10%)

The semiconductor device and the method for manufacturing the semiconductor device according to the present invention are not limited to the above embodiments. Moreover, the semiconductor device and the method for manufacturing a semiconductor device according to the present invention are not limited by the above-described effects. Various modifications can be made to the semiconductor device and the method of manufacturing the semiconductor device according to the present invention without departing from the gist of the present invention.

For example, in the method of manufacturing a semiconductor device according to the above-described embodiment, an example will be described in which a plurality of semiconductor chips are sequentially attached to a die pad of a lead frame substrate while one collet is heated and cooled while an adhesive sheet is interposed. However, the example of attaching a plurality of semiconductor chips to the lead frame substrate is not limited to this.
For example, while alternately heating and cooling two or more collets, a plurality of semiconductor chips may be sequentially attached to the die pad of the lead frame substrate with an adhesive sheet interposed therebetween.
In this way, after attaching one semiconductor chip of the plurality of semiconductor chips to one die pad of the lead frame substrate by one collet, waiting for the one collet to cool below the predetermined temperature. Instead, other semiconductor chips of the plurality of semiconductor chips can be attached to other die pads of the leadframe substrate by other collets.
As a result, the tact time can be shortened in the manufacture of semiconductor devices.

Also, in the method of manufacturing a semiconductor device according to the above-described embodiment, an example using a collet as the first pressing member has been described, but the first pressing member is not limited to the collet. If it is a member that can press a plurality of semiconductor chips against a plurality of die pads of the lead frame substrate while being sequentially heated (for example, the area of the pressing surface in plan view is 0.9 times the area of the semiconductor chip in plan view). Any member can be used as long as it is a member that is 1.1 times or less.

EXAMPLES Next, the present invention will be described more specifically with reference to examples. The following examples are intended to further illustrate the invention and are not intended to limit the scope of the invention.

<Laminate>
Using a hybrid mixer (trade name “HM-500”, manufactured by Keyence Corporation), a varnish was prepared by mixing for 3 minutes a composition in which the following materials were blended in the following mass ratio in the stirring mode of the hybrid mixer. .

Sinterable metal particles: 93.2 parts by mass The sinterable metal particles are first silver particles (trade name “DF-SNI-003” manufactured by DOWA, volume average particle diameter D ₅₀ is 60 nm) and Mixed particles of second silver particles (SPQ05S, manufactured by Mitsui Mining & Smelting Co., Ltd., volume average particle diameter _D50 is 1.1 μm), the mass ratio of the first silver particles is 83.9% by mass, and the second silver particles is 9.3% by mass.
Polymer binder: 1.4 parts by mass The polymer binder is polycarbonate resin (trade name “QPAC40”, manufactured by Empower Materials, weight average molecular weight 150000, solid at room temperature), which is a thermally decomposable polymer binder. be.
Low-molecular-weight binder: 5.4 parts by mass The low-molecular-weight binder is isobornylcyclohexanol (trade name: "Terusolve MTPH", manufactured by Nippon Terpene Chemical Industry Co., Ltd., liquid at room temperature), which is a low boiling point binder.
• Methyl ethyl ketone (MEK): appropriate amount Methyl ethyl ketone is used to adjust the viscosity of the varnish.

The varnish prepared as described above was applied to a porous polyethylene sheet (porous PE sheet) (thickness: 300 µm) as a base sheet and then dried to form an adhesive layer (adhesive sheet) having a thickness of 54 µm. , to obtain a laminate. The drying temperature was 110° C. and the drying time was 3 minutes. The content ratio (particle filling rate) of the sinterable metal particles in the adhesive layer (adhesive sheet) was 93.2% by mass.

(Production of semiconductor chip with adhesive sheet)
A semiconductor chip with an adhesive sheet was produced using FC3000W manufactured by Toray Engineering Co., Ltd.
First, after heating a collet of FC3000W to 90° C., one surface side of a Si mirror chip (planar dimension 5 mm×5 mm, thickness 200 μm) plated with silver on the entire surface is attached to the adhesive layer ( adhesive sheet) (the adhesive layer of the laminate was pressed on one side). Pressing (pressing) was performed by applying a load of 50 N for 5 seconds.
Next, by separating the collet from the laminate at a speed of 0.3 mm/sec, a semiconductor chip with an adhesive sheet attached to the collet was obtained.

[Example 1]
(Production of substrate with semiconductor chip)
By attaching three semiconductor chips with adhesive sheets to three die pads of a Cu lead frame substrate plated with Ag (hereinafter also referred to as an Ag-plated Cu lead frame substrate, thickness 3 mm), a semiconductor chip with a semiconductor chip is attached. A substrate was produced.
Attachment of the semiconductor chip with the adhesive sheet to the die pad of the Ag-plated Cu lead frame substrate was mainly performed using FC3000W manufactured by Toray Engineering Co., Ltd. Specifically, it was carried out as follows.
The Ag-plated Cu lead frame substrate was placed on a FC3000W stage and heated to 150.degree.

(1) The collet is heated to 100° C. in a state in which a semiconductor chip with an adhesive sheet (hereinafter referred to as a first semiconductor chip with an adhesive sheet) is attached to the collet.
(2) With the collet heated to 100° C., the collet is lowered vertically to attach the adhesive sheet of the first semiconductor chip with the adhesive sheet to the first die pad of the Ag-plated Cu lead frame substrate. abut.
(3) pressing the first semiconductor chip with the adhesive sheet with the collet while the adhesive sheet of the first semiconductor chip with the adhesive sheet is in contact with the first die pad of the Ag-plated Cu lead frame substrate; While pressing (pressing), the collet is heated to 250° C. to sinter the sinterable metal particles in the adhesive sheet (primary sintering), and the adhesive sheet is attached to the first die pad. Attach the attached first semiconductor chip. The pressing (pressing) by the collet is performed at 10 MPa. Moreover, pressurization heating time shall be 100 sec.
(4) After the collet is lifted and separated from the adhesive sheet-attached first semiconductor chip, the temperature of the collet is lowered to a temperature (50° C.) at which the sinterable metal particles are difficult to sinter. Let
(5) Using the collet, in the same manner as described above, a semiconductor chip with a second adhesive sheet attached to the collet is obtained, and the collet is heated to 100.degree.
(6) As in (2) and (3) above, the second semiconductor chip with the adhesive sheet is attached to the second die pad of the Ag-plated Cu lead frame substrate.
(7) In the same manner as in (4) above, after separating the collet from the second semiconductor chip with the adhesive sheet by lifting the collet, the temperature of the collet is lowered so that the sinterable metal particles are difficult to sinter. temperature (50° C.).
(8) A third semiconductor chip with an adhesive sheet is attached to the third die pad of the Ag-plated Cu lead frame substrate by the collet in the same manner as described above.

As described above, an Ag-plated Cu lead frame substrate with semiconductor chips according to Example 1 was obtained, in which three semiconductor chips were attached to the Ag-plated Cu lead frame substrate with the adhesive sheet interposed.

(Measurement of shear strength)
The shear strength at 25° C. was measured for the Ag-plated Cu lead frame substrate with a semiconductor chip according to Example 1 obtained as described above.
Specifically, the shear strength at 25° C. was measured using a universal bond tester series 4000 manufactured by Nordson Advanced Technologies under the following conditions.

<Shear strength measurement conditions>
・Load cell: DS100kg
・Measurement range: 100kg
・Test type: Destructive test ・Test speed: 100 μm/s
・Descent speed: 100 μm/s
・Test height: 100 μm
・Tool movement amount: 2000 μm
・ Destruction recognition point: low (10%)

The shear strength at 25° C. was obtained by measuring each of the semiconductor chips with the first adhesive sheet to the semiconductor chip with the third adhesive sheet and averaging these measured values.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 2]
(Production of substrate with semiconductor chip)
After removing the Ag-plated Cu lead frame substrate on which the first to third semiconductor chips are attached from the stage of FC3000W, it is placed in a dryer heated to 250 ° C. and heated for 10 minutes. An Ag-plated Cu lead frame substrate with a semiconductor chip according to Example 2 was obtained in the same manner as in Example 1, except that the contained sinterable metal particles were further sintered (secondary sintering).
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 3]
(Production of substrate with semiconductor chip)
Semiconductor chips were attached to the Ag-plated Cu lead frame substrate in the same manner as in Example 2, except that the pressure and heating time was set to 10 sec. A semiconductor chip-attached Ag-plated Cu lead frame substrate according to Example 3 was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 4]
(Production of substrate with semiconductor chip)
The semiconductor chip was attached to the Ag-plated Cu lead frame substrate in the same manner as in Example 2 except that the pressing (pressing) by the collet was performed at 20 MPa, and the Ag-plated Cu lead was interposed with the adhesive sheet. An Ag-plated Cu lead frame substrate with semiconductor chips according to Example 4, in which three semiconductor chips were attached to the frame substrate, was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 5]
(Production of substrate with semiconductor chip)
A semiconductor chip was attached to an Ag-plated Cu lead frame substrate in the same manner as in Example 1, except that primary sintering was performed by heating the collet to 300° C., and an adhesive sheet was interposed. A lead frame substrate with semiconductor chips according to Example 5, in which three semiconductor chips were attached to the Ag-plated Cu lead frame substrate, was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 6]
(Production of substrate with semiconductor chip)
The semiconductor chip was attached to the Ag-plated Cu lead frame substrate in the same manner as in Example 1 except that primary sintering was performed by heating the collet to 450 ° C. and the pressure heating time was set to 5 seconds, An Ag-plated Cu leadframe substrate with semiconductor chips according to Example 6 was obtained, in which three semiconductor chips were attached to the Ag-plated Cu leadframe substrate with an adhesive sheet interposed therebetween.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 7]
(Production of substrate with semiconductor chip)
Pd-PPF (Palladium Pre Plated Lead Frame. Cu lead frame plated with Ni, Pd and Au in this order. Thickness 0.2 mm). A substrate with a semiconductor chip was produced by attaching a semiconductor chip with an adhesive sheet.
The attachment of the semiconductor chip with the adhesive sheet to the Pd-PPF die pad was mainly performed using FC3000W manufactured by Toray Engineering Co., Ltd. Specifically, it was carried out as follows.
The Pd-PPF was placed on the stage of FC3000W and was not heated (the stage temperature was 25° C.).

(1) The collet is heated to 100° C. in a state in which a semiconductor chip with an adhesive sheet (hereinafter referred to as a first semiconductor chip with an adhesive sheet) is attached to the collet.
(2) With the collet heated to 100° C., the collet is lowered vertically to bring the adhesive sheet of the first semiconductor chip with the adhesive sheet into contact with the first die pad of the Pd-PPF. .
(3) With the adhesive sheet of the first semiconductor chip with the adhesive sheet in contact with the first die pad of the Pd-PPF, while pressing the first semiconductor chip with the adhesive sheet with the collet (pressing while), by heating the collet to 300° C., the sinterable metal particles in the adhesive sheet are sintered (primary sintering), and the first die pad with the adhesive sheet is formed. 1 Attach a semiconductor chip. The pressing (pressing) by the collet is performed at 10 MPa. Moreover, pressurization heating time shall be 5 sec.
(4) After the collet is lifted and separated from the adhesive sheet-attached first semiconductor chip, the temperature of the collet is lowered to a temperature (50° C.) at which the sinterable metal particles are difficult to sinter. Let
(5) Using the collet, in the same manner as described above, a semiconductor chip with a second adhesive sheet attached to the collet is obtained, and the collet is heated to 100.degree.
(6) As in (2) and (3) above, the second semiconductor chip with the adhesive sheet is attached to the second die pad of the Pd-PPF.
(7) In the same manner as in (4) above, after separating the collet from the second semiconductor chip with the adhesive sheet by lifting the collet, the temperature of the collet is lowered so that the sinterable metal particles are difficult to sinter. temperature (50° C.).
(8) A third semiconductor chip with an adhesive sheet is attached to the third die pad of Pd-PPF by the collet in the same manner as described above.

As described above, a semiconductor chip-attached Pd-PPF according to Example 7, in which three semiconductor chips were attached to the Pd-PPF with the adhesive sheet interposed, was obtained.
In addition, in Example 7, secondary sintering was not performed.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 8]
(Production of substrate with semiconductor chip)
After pressing (pressing) with the collet at 5 MPa and removing the Pd-PPF attached with the first to third semiconductor chips (Pd-PPF after (8) in Example 7 above) from the stage of FC3000W , except that this was placed in a dryer heated to 300 ° C. and heated for 60 minutes to further sinter the sinterable metal particles contained in the adhesive sheet (secondary sintering). In the same manner as in Example 8, semiconductor chips were attached to Pd-PPF, and three semiconductor chips were attached to Pd-PPF with an adhesive sheet interposed. Pd- with semiconductor chips according to Example 8 PPF was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 9]
(Production of substrate with semiconductor chip)
The semiconductor chips were attached to the Pd-PPF in the same manner as in Example 7, except that the FC3000W stage was heated to 150 ° C., and three semiconductor chips were attached to the Pd-PPF with an adhesive sheet interposed. A Pd-PPF with the attached semiconductor chip according to Example 9 was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 10]
(Production of substrate with semiconductor chip)
The semiconductor chip was attached to the Pd-PPF in the same manner as in Example 7, except that the collet was heated to 400 ° C. to perform primary sintering, and the Pd-PPF with an adhesive sheet interposed. A semiconductor chip-attached Pd-PPF according to Example 10 was obtained, in which three semiconductor chips were attached to the .
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 11]
(Production of substrate with semiconductor chip)
After removing the Pd-PPF attached with the first to third semiconductor chips (the Pd-PPF after (8) in Example 7 above) from the FC3000W stage, it was placed in a dryer heated to 300°C. Semiconductor chips to Pd-PPF in the same manner as in Example 10, except that the sinterable metal particles contained in the adhesive sheet were further sintered (secondary sintering) by heating for 60 minutes. to obtain a semiconductor chip-attached Pd-PPF according to Example 11, in which three semiconductor chips were attached to the Pd-PPF with an adhesive sheet interposed therebetween.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 12]
<Laminate>
Using a hybrid mixer (trade name “HM-500”, manufactured by Keyence Corporation), a mixture containing each material at the mass ratio shown in Table 1 below was stirred and mixed in a “stirring mode” to prepare a varnish.
Stirring and mixing by the hybrid mixer were performed in three steps. Specifically, first, a primary mixture containing a thermosetting resin and a thermoplastic resin as a polymer binder is stirred and mixed for 3 minutes (primary stirring), and then conductive particles and a low-molecular binder are added to the primary mixture. A secondary mixture obtained by adding a volatile material is stirred and mixed for 6 minutes (secondary mixing), and a tertiary mixture obtained by adding a catalyst and a solvent to the secondary mixture is stirred and mixed for 3 minutes (tertiary mixing). It was done by
After applying this varnish to one side of a release treatment film (trade name “MRA38”, manufactured by Mitsubishi Chemical Corporation, thickness 38 μm), it is dried at a temperature of 100 ° C. for 2 minutes to form an adhesive layer (adhesion layer) with a thickness of 30 μm. sheet) to obtain a laminate.
In addition, as each material shown in the following Table 1, the following were used.

・ Phenolic resin MEHC-7851S manufactured by Meiwa Kasei Co., Ltd. (bisphenol type phenolic resin, phenol equivalent 209 g / eq)
・ Solid epoxy resin KI-3000-4 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. (cresol novolac type polyfunctional epoxy resin, epoxy equivalent 200 g / eq)
Liquid epoxy resin DIC EXA-4816 (aliphatic modified bisphenol A type epoxy resin (bifunctional type), epoxy equivalent 403 g / eq)
・Silver (Ag)-coated copper (Cu) particles Dowa Electronics Co., Ltd. product name AOP-TCY-16 (EN) (Spherical copper particles coated with 20% by mass of silver particles. Particle shape is spherical. Volume average particle Diameter _D50 is 2.8 μm)
・Silver (Ag) particles Dowa Electronics Co., Ltd. trade name AG-2-47J (surface-treated silver particles. Particle shape is spherical. Volume average particle diameter _D50 is 0.5 μm)
・Volatile material (isobornylcyclohexanol (MTPH))
MTPH manufactured by Nippon Terpene Co., Ltd.
・ Acrylic resin Teisan Resin SG-70L manufactured by Nagase Chemitex Co., Ltd. (containing MEK and toluene as solvents, solid content 12.5% by mass, glass transition temperature -13 ° C., mass average molecular weight 900,000, acid value 5 mg / KOH, Carboxy group-containing acrylic copolymer)
Coupling agent KBE-846 (bis (triethoxysilylpropyl) tetrasulfide) manufactured by Shin-Etsu Chemical Co., Ltd.
・ Catalyst TPP-MK (tetraphenylphosphonium tetra-p-tolylborate) manufactured by Hokko Chemical Industry Co., Ltd.
・Solvent methyl ethyl ketone (MEK)

(Production of semiconductor chip with adhesive sheet)
A semiconductor chip with an adhesive sheet was produced in the same manner as in Example 1, except that the adhesive sheet configured as described above was used.
(Production of substrate with semiconductor chip)
The semiconductor chip was attached to the Pd-PPF in the same manner as in Example 10, except that the collet was pressed (pressed) at 3 MPa, and three pieces were attached to the Pd-PPF with an adhesive sheet interposed. A semiconductor chip-attached Pd-PPF according to Example 12, to which the semiconductor chip was attached, was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 13]
<Laminate>
In the same manner as in Example 12, a laminate in which an adhesive layer (adhesive sheet) having a thickness of 30 μm was formed on one surface of a release treated film (trade name “MRA38”, manufactured by Mitsubishi Chemical Corporation, thickness 38 μm). got
(Production of semiconductor chip with adhesive sheet)
A semiconductor chip with an adhesive sheet was produced in the same manner as in Example 1, except that the adhesive sheet configured as described above was used.
(Production of substrate with semiconductor chip)
Using the adhesive sheet configured as described above, primary sintering was performed by heating the collet to 400° C., and pressing (pressing) with the collet was performed at 3 MPa in the same manner as in Example 8. , Pd-PPF with semiconductor chips according to Example 13, in which three semiconductor chips are attached to Pd-PPF and three semiconductor chips are attached to Pd-PPF with an adhesive sheet interposed. Obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Example 14]
<Laminate>
In the same manner as in Example 12, a laminate in which an adhesive layer (adhesive sheet) having a thickness of 30 μm was formed on one surface of a release treated film (trade name “MRA38”, manufactured by Mitsubishi Chemical Corporation, thickness 38 μm). got
(Production of semiconductor chip with adhesive sheet)
A semiconductor chip with an adhesive sheet was produced in the same manner as in Example 1, except that the adhesive sheet configured as described above was used.
(Production of substrate with semiconductor chip)
Three semiconductor chips were attached to Pd-PPF in the same manner as in Example 12, except that the FC3000W stage temperature was heated to 150 ° C., and three semiconductor chips were attached to Pd-PPF with an adhesive sheet interposed. A semiconductor chip-attached Pd-PPF according to Example 14, to which the semiconductor chip was attached, was obtained.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Comparative Example 1]
(Production of substrate with semiconductor chip)
A substrate with a semiconductor chip was produced as follows.
First, three semiconductor chips with adhesive sheets were temporarily fixed to three die pads of an Ag-plated Cu lead frame substrate. As the adhesive sheet, the one described in the section of Example 1 was used.
FC3000W manufactured by Toray Engineering Co., Ltd. was used to temporarily fix the semiconductor chip with the adhesive sheet to the die pad of the Ag-plated Cu lead frame substrate. Specifically, it was carried out as follows.
The Ag-plated Cu lead frame substrate was placed on the FC3000W stage.

(1) The collet is heated to 50° C. in a state in which a semiconductor chip with an adhesive sheet (hereinafter referred to as a first semiconductor chip with an adhesive sheet) is attached to the collet.
(2) While pressing the semiconductor chip with the first adhesive sheet from the side of the adhesive sheet to the first die pad of the Ag-plated Cu lead frame substrate with the collet (while pressing), the first die pad with the adhesive sheet is pressed against the first die pad. Attach the semiconductor chip. The pressing (pressing) by the collet is performed at 0.01 MPa. Moreover, pressurization time shall be 1 second.
(3) By lifting the collet, it is separated from the first semiconductor chip with the adhesive sheet.
(4) Using the collet, in the same manner as described above, a second semiconductor chip with an adhesive sheet attached to the collet is obtained. 2. Attach the semiconductor chip to the second die pad of the Ag-plated Cu lead frame. After attaching the second semiconductor chip with the adhesive sheet to the second die pad of the Ag-plated Cu lead frame, the collet is lifted to separate from the second semiconductor chip with the adhesive sheet.
(5) Using the collet, in the same manner as described above, a third semiconductor chip with an adhesive sheet attached to the collet is obtained. 3. Attach the semiconductor chip to the third die pad of the Ag-plated Cu lead frame. After attaching the third semiconductor chip with the adhesive sheet to the third die pad of the Ag-plated Cu lead frame, the collet is lifted to separate from the third semiconductor chip with the adhesive sheet.

As described above, the semiconductor chip with the adhesive sheet was temporarily fixed to the Ag-plated Cu lead frame substrate.
Next, a semiconductor chip with an adhesive sheet was attached (fixed) to the Ag-plated Cu lead frame substrate. Attaching (fixing) the semiconductor chip to the Ag-plated Cu lead frame substrate was performed using HTM-3000 manufactured by Hakuto Kiko. Specifically, it was carried out as follows.
The Ag-plated Cu lead frame substrate to which the semiconductor chip with the adhesive sheet was temporarily fixed was placed on the stage of the HTM-3000.

(1′) While pressing a parallel plate from the first semiconductor chip with the adhesive sheet to the third semiconductor chip with the adhesive sheet from above and below the stage (while being pressed by the parallel plate), the stage temperature is lowered to 200°C. to sinter the sinterable metal particles in the adhesive sheet (primary sintering), thereby separating the first semiconductor chip with the adhesive sheet from the third semiconductor chip with the adhesive sheet into the It is attached (fixed) to an Ag-plated Cu lead frame. The pressing (pressing) by the parallel plate is performed at 10 MPa. Moreover, pressurization heating time shall be 150 sec.

As described above, an Ag-plated Cu leadframe substrate with semiconductor chips according to Comparative Example 1, in which three semiconductor chips were attached to the Ag-plated Cu leadframe substrate with the adhesive sheet interposed, was obtained.

(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Comparative Example 2]
(Production of substrate with semiconductor chip)
After performing the above (1′), the pressing state of the parallel plates is released (as no pressure is applied), and the Ag-plated Cu lead frame substrate on which the first to third semiconductor chips are attached (fixed) After being removed from the HTM-3000 stage, it is placed in a dryer heated to 250° C. and heated for 10 minutes to further sinter the sinterable metal particles contained in the adhesive sheet (secondary firing). Conclusion) The procedure was carried out in the same manner as in Comparative Example 1 except that it was made.
Then, an Ag-plated Cu leadframe substrate with a semiconductor chip according to Comparative Example 2 was obtained, in which three semiconductor chips were attached to the Ag-plated Cu leadframe substrate with an adhesive sheet interposed therebetween.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

[Comparative Example 3]
(Production of substrate with semiconductor chip)
The same procedure as in Comparative Example 1 was performed except that the stage temperature of HTM-3000 was changed to 300.degree.
Then, an Ag-plated Cu leadframe substrate with a semiconductor chip according to Comparative Example 3 was obtained, in which three semiconductor chips were attached to the Ag-plated Cu leadframe substrate with an adhesive sheet interposed therebetween.
(Measurement of shear strength)
The shear strength at 25° C. was measured in the same manner as in Example 1.
The measurement results of shear strength at 25° C. are shown in Table 2 below.

Also, for each example, the standard deviation was calculated for the shear strength at 25°C and the shear strength at 250°C. Standard deviations are also shown in Table 2 below.

From Table 2, in Examples 1 to 14, the standard deviation of the shear strength at 25 ° C. is 7 or less, and there is no adhesion unevenness among the three semiconductor chips attached to the substrate with the adhesive sheet interposed. It can be seen that it is relatively small.
On the other hand, in Comparative Examples 1 to 3, the standard deviation of the shear strength at 25° C. is 8 or more, and there is no adhesion unevenness among the three semiconductor chips attached to the substrate with the adhesive sheet interposed therebetween. It can be seen that it is relatively large.

1 base sheet, 2 adhesive sheet, 10 laminate,
A collet, B1 first semiconductor chip, B2 second semiconductor chip C dicing tape, D lead frame substrate, E1 first die pad, E2 second die pad, F heating and pressurizing device G stage, H stage.

Claims (7)

a plurality of semiconductor chips;
a substrate having a plurality of mounting areas on which the plurality of semiconductor chips are mounted;
a plurality of adhesive sheets containing sinterable metal particles that can be sintered by heating at a temperature of 400° C. or less;
a first pressing member that presses the semiconductor chip toward the substrate with the adhesive sheet interposed therebetween to bond the plurality of semiconductor chips to the plurality of mounting regions;
performing a semiconductor chip mounting step of sequentially pressing the plurality of semiconductor chips with the first pressing member to bond them to the plurality of mounting regions;
In the semiconductor chip mounting step, the semiconductor chip is pressed using the first pressing member heated to a temperature at which the sinterable metal particles can be sintered.
A method of manufacturing a semiconductor device. After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
2. The method of manufacturing a semiconductor device according to claim 1, wherein in said secondary heating step, said heating is performed without pressing part or all of said plurality of semiconductor chips against said substrate. 3. The method of manufacturing a semiconductor device according to claim 2, wherein in said secondary heating step, said heating is performed without pressing all of said plurality of semiconductor chips toward said substrate. After the semiconductor chip mounting step,
further performing a secondary heating step of heating the substrate to which the plurality of semiconductor chips are attached at a temperature at which the sinterable metal particles can be sintered;
2. The method of manufacturing a semiconductor device according to claim 1, wherein in said secondary heating step, said heating is performed while pressing some or all of said plurality of semiconductor chips toward said substrate. 5. The method of manufacturing a semiconductor device according to claim 4, wherein in said secondary heating step, said heating is performed while pressing all of said plurality of semiconductor chips toward said substrate. 6. The method of manufacturing a semiconductor device according to claim 1, wherein said first pressing member is heated to a temperature of 250[deg.] C. or higher in said semiconductor chip mounting step. A semiconductor device manufactured by the method for manufacturing a semiconductor device according to any one of claims 1 to 6,
A semiconductor device, wherein a shear strength at 25° C. between one semiconductor chip of the plurality of semiconductor chips and the mounting region is 2 MPa or more.

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