JP7045052B2 - Semiconductor mounting method - Google Patents

Description

The present invention relates to a semiconductor mounting method using a film-shaped semiconductor encapsulant.

In order to meet the demand for narrowing the gap between the semiconductor chip and the substrate, a semiconductor mounting method using a film-shaped semiconductor encapsulant has been proposed.

The semiconductor mounting method using the film-shaped semiconductor encapsulant is carried out by the following procedure.
(1) A film-shaped semiconductor encapsulant is laminated on one surface of a semiconductor wafer having electrodes on the circuit surface.
(2) The semiconductor wafer is diced and separated into individual pieces.
(3) The surface of the fragmented semiconductor wafer (semiconductor chip) on which the film-shaped semiconductor encapsulant is laminated is thermocompression bonded (TCB) to the substrate using a flip chip bonder or the like. ..

In semiconductor mounting using a film-shaped semiconductor encapsulant, good bondability and a sealed state without defects such as voids are required. Film-shaped semiconductor encapsulant compositions and mounting methods have been proposed to achieve these defect-free encapsulation states. In order to eliminate void defects, film-like semiconductor encapsulation is performed under a pressurized atmosphere after TCB. A method of curing the material is also being studied (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-126120

The method of curing the film-like semiconductor encapsulant under a pressurized atmosphere after the TCB is performed is effective for curing without void defects, but a sufficient effect is obtained if the void volume before curing is too large. It became clear that it could not be done.
In order to prevent such defects from occurring, it is an object of the present invention to provide a semiconductor mounting method that more reliably cures under a pressurized atmosphere and does not cause defects.

In the present invention, the film-shaped semiconductor encapsulant is laminated on a semiconductor chip on which a protruding electrode containing solder is formed, the film-shaped semiconductor encapsulant is heat-pressed against the substrate, and then the film-shaped semiconductor encapsulant is sealed. In a method of mounting a semiconductor device in which a stop material is heat-cured and a semiconductor chip is mounted on the substrate.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip is 2.2 μm or less, and the lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
Provided is a method (1) for mounting a semiconductor device in which the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more.

Further, in the present invention, the film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, the film-shaped semiconductor encapsulant is heat-pressed against a substrate, and then the film-shaped semiconductor encapsulant is heat-pressed. In a method for mounting a semiconductor device in which a semiconductor encapsulant is heat-cured and a semiconductor chip is mounted on the substrate.
The process of individualizing a semiconductor wafer laminated with the film-shaped semiconductor encapsulant.
The process of aligning the individualized semiconductor chip with the substrate electrode,
It has a step of pressure-welding the aligned semiconductor chip and the substrate while heating, and a step of heat-curing the film-shaped semiconductor encapsulant under a pressure atmosphere after the pressure welding.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor wafer and then separated into pieces is 2.2 μm or less.
The lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
Provided is a method (2) for mounting a semiconductor device in which the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more.

Further, in the present invention, the film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, the film-shaped semiconductor encapsulant is heat-pressed against a substrate, and then the film-shaped semiconductor encapsulant is heat-pressed. In a method for mounting a semiconductor device in which a semiconductor encapsulant is heat-cured and a semiconductor chip is mounted on the substrate.
A step of reducing the thickness of a semiconductor wafer on which the film-shaped semiconductor encapsulant is laminated by polishing.
The process of individualizing a semiconductor wafer laminated with the film-shaped semiconductor encapsulant.
The process of aligning the individualized semiconductor chip with the substrate electrode,
The process of pressure-welding the aligned semiconductor chip and the substrate while heating, and
It has a step of heating and curing the film-like semiconductor encapsulant under a pressure atmosphere after pressure welding.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor wafer and then separated into pieces is 2.2 μm or less.
The lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
Provided is a method (3) for mounting a semiconductor device in which the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more.

In the semiconductor mounting methods (1) to (3) of the present invention, it is preferable that the protruding electrodes have a structure in which a copper layer and a solder layer are laminated in this order on a semiconductor chip surface or a semiconductor wafer surface.

In the semiconductor mounting methods (1) to (3) of the present invention, the height of the protruding electrode is preferably 5 μm or more and 50 μm or less.

According to the semiconductor mounting methods (1) to (3) of the present invention, defects such as void defects can be prevented and a reliable connection can be achieved.

Hereinafter, the present invention will be described in detail.

In the method (1) for mounting a semiconductor device of the present invention, a film-shaped semiconductor encapsulant is laminated on a semiconductor chip on which a protruding electrode containing solder is formed, and then the film-shaped semiconductor encapsulant is heat-pressed against a substrate. Then, the film-shaped semiconductor encapsulant is heat-cured to mount the semiconductor chip on the substrate.
In the mounting method (1) of the semiconductor device of the present invention, it is required to satisfy the following conditions (A) to (D).

Condition (A)
The thickness of the film-shaped semiconductor encapsulant shall be 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The condition (A) prevents oversupply and shortage of the film-shaped semiconductor encapsulant. If the thickness of the film-shaped semiconductor encapsulant is less than 0.8 times the height of the protruding electrode, the film-shaped semiconductor encapsulant is insufficient, and mounting defects such as void defects and delamination occur. If the thickness of the film-shaped semiconductor encapsulant is more than 1.3 times the height of the protruding electrode, the film-shaped semiconductor encapsulant will be oversupplied, and the film-shaped semiconductor encapsulant will crawl onto the semiconductor chip. It will rise and the mounting will be defective.
The thickness of the film-shaped semiconductor encapsulant is preferably 0.9 times or more and 1.25 times or less the height of the protruding electrode.

Condition (B)
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip shall be 2.2 μm or less.
According to the condition (B), the void volume generated when the film-shaped semiconductor encapsulant and the substrate come into contact with each other can be reduced, and mounting defects due to void defects can be prevented. If the difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip is more than 2.2 μm, the void volume generated when the film-like semiconductor encapsulant and the substrate come into contact with each other is large. This causes mounting defects due to void defects.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip is more preferably 2 μm or less.

Condition (C)
The lamination pressure when laminating the film-shaped semiconductor encapsulant on the semiconductor chip is 0.1 MPa or more and 0.8 MPa or less.
Depending on the condition (C), the void volume generated when the film-shaped semiconductor encapsulant and the substrate come into contact with each other can be reduced, and mounting defects due to void defects can be prevented. When the lamination pressure exceeds 0.8 MPa, the film-shaped semiconductor encapsulant becomes thin, the difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip becomes large, voids occur, and mounting defects occur. Will be. In addition, the protruding electrode may be damaged. If the lamination pressure is less than 0.1 MPa, poor adhesion of the film-shaped semiconductor encapsulant occurs due to underpressure, and poor connection or mounting failure due to void defects occurs.

Condition (D)
The film-shaped semiconductor encapsulant is heat-cured in a pressurized atmosphere of 0.4 MPa or more.
According to the condition (D), the curing of the film-shaped semiconductor encapsulant can be promoted while suppressing the generation and expansion of voids, and mounting defects due to void defects can be prevented. When the film-shaped semiconductor encapsulant is heat-cured in an atmosphere of less than 0.4 MPa, the generation and expansion of voids cannot be suppressed, and mounting defects due to void defects occur.

In the method (2) for mounting a semiconductor device of the present invention, a film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, and then the film-shaped semiconductor encapsulant is heat-pressed against a substrate. Then, the film-shaped semiconductor encapsulant is heat-cured to mount the semiconductor chip on the substrate.
The method (2) for mounting a semiconductor device of the present invention includes the following steps (a) to (d).
(A) Step of individualizing a semiconductor wafer laminated with a film-like semiconductor encapsulant (b) Step of aligning the fragmented semiconductor chip with a substrate electrode (c) With the aligned semiconductor chip Step of pressure contacting with the substrate while heating (d) Step of heating and curing the film-shaped semiconductor encapsulant in a pressure atmosphere after pressure welding

While the target for laminating the film-shaped semiconductor encapsulant is a semiconductor wafer, the target for mounting on the substrate is a semiconductor chip.
Therefore, in the step (a), the semiconductor wafer is individualized by dicing to obtain a semiconductor chip on which the film-shaped semiconductor encapsulant is laminated.
Next, in step (b), while recognizing the alignment reference marks formed on the semiconductor chip and the substrate with a camera for visible light or the like, the individualized semiconductor chip is used as a substrate electrode. Align.
Next, in the step (c), the fragmented semiconductor chip is heat-pressed (TCB) with respect to the substrate using a flip chip bonder or the like. Here, the mounting of the semiconductor chip on the substrate and the connection between the projection electrode and the substrate electrode may be carried out at the same time, or the projection electrode and the substrate electrode may be connected after the semiconductor chip is mounted on the substrate. .. In the former case, TCB is carried out in a state of being heated to a temperature higher than the solder melting temperature. In the latter case, the semiconductor chip is mounted at a predetermined position on the substrate while being heated to the softening temperature or higher of the film-shaped semiconductor encapsulant, and further heated to the solder melting temperature or higher to form the protruding electrode and the substrate electrode. To connect. Further, in the latter case, the semiconductor chips may be individually heated to a temperature higher than the solder melting temperature to connect the protrusion electrodes and the substrate electrodes, or a plurality of semiconductor chips may be heated simultaneously to connect the protrusion electrodes and the substrate electrodes. You may.
Next, in step (d), the film-shaped semiconductor encapsulant is heat-cured under a pressure atmosphere, and the semiconductor chip is mounted on the substrate.

Also in the mounting method (2) of the semiconductor device of the present invention, it is required to satisfy the above-mentioned conditions (A) to (D). The points to be noted in the mounting method (2) of the semiconductor device of the present invention are shown below.
Since the semiconductor wafer is fragmented into semiconductor chips by the above step (a), it has a plurality of protruding electrodes according to the number of semiconductor chips after fragmentation. It is required that the condition (A) is satisfied for these plurality of protruding electrodes.
On the other hand, the condition (B) is required to be satisfied after the above step (a) is performed, that is, the semiconductor chip is separated into individual pieces.

In the method (3) for mounting a semiconductor device of the present invention, a film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, and then the film-shaped semiconductor encapsulant is heat-pressed against a substrate. After that, the film-shaped semiconductor encapsulant is heat-cured to mount the semiconductor chip on the substrate, which is the same as the mounting method (2) of the semiconductor device of the present invention. Therefore, the method (3) for mounting the semiconductor device of the present invention includes the above steps (a) to (d). However, the semiconductor device mounting method (3) of the present invention includes the following step (e) to be carried out before the step (a).
(E) The step step (e) of reducing the thickness of the semiconductor wafer on which the film-shaped semiconductor encapsulant is laminated by polishing is a so-called backgrinding step.

Also in the mounting method (3) of the semiconductor device of the present invention, it is required to satisfy the above-mentioned conditions (A) to (D). The points to be noted in the semiconductor device mounting method (3) of the present invention are the same as the points to be noted in the semiconductor device mounting method (2) of the present invention.

The mounting methods (1) to (3) of the semiconductor device of the present invention will be further described.

The semiconductor chip used in the mounting method (1) of the semiconductor device of the present invention has at least one protruding electrode. The number of protruding electrodes matches the number of substrate electrodes on the substrate on which the semiconductor chip is mounted.
The semiconductor wafer used in the mounting methods (2) and (3) of the semiconductor device of the present invention has a plurality of protruding electrodes according to the number of semiconductor chips after individualization.
These protruding electrodes may be composed of a single or composite structure of solder, gold, copper, etc., but have a structure in which a copper layer and a solder layer are laminated in this order on a semiconductor chip surface or a semiconductor wafer surface. It is preferable to have.
Further, it is preferable that the height of these protruding electrodes is 5 μm or more and 50 μm or less.
The semiconductor chip or semiconductor wafer is not particularly limited, and may be a silicon chip or a silicon wafer, or may be a compound semiconductor chip or a compound semiconductor wafer.

The film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention preferably satisfies the following conditions.

The film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention preferably has transparency to visible light. Specifically, it is preferable that the transmittance of light having a wavelength of 550 nm is 15% or more.
When the transmittance of light having a wavelength of 550 nm is 15% or more, when the alignment reference mark is formed on the semiconductor chip, the semiconductor wafer, or the substrate, these are passed through the film-like semiconductor encapsulant. This is because the reference mark of can be recognized by a camera for visible light or the like.

Further, it is preferable that the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention does not generate voids when the semiconductor chip is heat-pressed (TCB) with respect to the substrate. For example, when a semiconductor chip is heat-pressed (TCB) with respect to a substrate, it is heated to 230 ° C. or higher, so that voids may occur due to resin foaming caused by thermal decomposition of the resin material constituting the film-shaped semiconductor encapsulant. There is. Therefore, as the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention, it is preferable to select a material that does not cause resin foaming at 230 ° C. or higher.

Further, it is desirable that the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention contains a thermosetting component and a curing agent thereof. Examples of the thermosetting component include epoxy resin, bismaleimide resin, polyamide resin, polyimide resin, triazine resin, cyanoacrylate resin, unsaturated polyester resin, melamine resin, urea resin, benzoxazine resin, polyurethane resin, and polyisocyanate. Examples thereof include resins, furan resins, resorcinol resins, xylene resins, benzoguanamine resins, diallyl phthalate resins, silicone resins, polyvinyl butyral resins, siloxane-modified epoxy resins, siloxane-modified polyamideimide resins, acrylate resins, and acrylic resins. Of these, epoxy resin, benzoxazine resin, siloxane-modified epoxy resin, and siloxane-modified polyamide-imide resin are particularly preferable from the viewpoint of heat resistance. These can be used alone or as a mixture of two or more. For example, the film-shaped semiconductor encapsulant may contain a mixture of a polyimide resin and an epoxy resin as a thermosetting component.

Examples of the curing agent contained in the film-shaped semiconductor encapsulant include amine-based curing agents such as aliphatic amines, alicyclic amines, aromatic polyamines, and tertiary amines, aliphatic acid anhydrides, and alicyclic acid anhydrides. Acid anhydride-based curing agents such as products and aromatic acid anhydrides, phenol-based curing agents such as novolak phenol resin, dicyandiamide, organic acid dihydrazide, boron trifluoride amine complex, imidazoles, polyamide, organic peroxide, etc. Can be mentioned. These can be used alone or as a mixture of two or more.

Further, the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention may contain a polymer resin other than the above-mentioned thermosetting component. Examples of the polymer resin include polyester resin, polyether resin, polyamide resin, polyamideimide resin, polyimide resin, polyacrylate resin, polyvinyl butyral resin, polyurethane resin, phenoxy resin, polyacrylate resin, polybutadiene, and acrylonitrile butadiene copolymer. , Acrylonitrile butadiene rubber styrene resin, styrene butadiene copolymer, acrylic acid copolymer and the like. These can be used alone or in combination of two or more. Among these, polyimide resin and phenoxy resin are preferable from the viewpoint of heat resistance and film formability.

Further, the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention may contain an inorganic filler for low thermal expansion. In this case, the filler type, particle size, blending amount, etc. are set so that the transmittance at a wavelength of 550 nm is 15% or more.

Furthermore, the film-shaped semiconductor encapsulant used in the mounting methods (1) to (3) of the semiconductor device of the present invention is a curing accelerator, a flux agent, a silane coupling agent, a titanium coupling agent, and an antioxidant. , Additives such as leveling agents and ion trapping agents, and elastomer components may be blended. These may be used alone or in combination of two or more. The blending amount may be adjusted so that the effect of each additive is exhibited.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, a known laminating device can be used when laminating a film-shaped semiconductor encapsulant on a semiconductor chip or a semiconductor wafer. The laminating device to be used is not particularly limited, and for example, a roll laminator or a vacuum laminator can be used.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, the lamination temperature and the lamination time when laminating the film-shaped semiconductor encapsulant on the semiconductor chip or the semiconductor wafer are the film-like to be used. It can be appropriately selected depending on the semiconductor encapsulant.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, the conditions for heat-pressing (TCB) the semiconductor chip to the substrate are not particularly limited, depending on the film-shaped semiconductor encapsulant and solder used. It may be selected as appropriate.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, the heating temperature and the heating time when the film-shaped semiconductor encapsulant is heat-cured under a pressure atmosphere are not particularly limited, and the film-shaped semiconductor used is not particularly limited. It may be appropriately selected according to the sealing material.

The step (a) in the mounting method (2) and (3) of the semiconductor device of the present invention can be achieved by using a general dicing device and performing dry or wet dicing.

The step (e) in the mounting method (3) of the semiconductor device of the present invention can be achieved by a general back grinder.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, even if the substrate before heat pressure welding (TCB) is subjected to surface treatment such as plasma treatment in order to improve adhesion, wettability, etc. good.

In the mounting methods (1) to (3) of the semiconductor device of the present invention, the portion where the semiconductor chip is mounted is sealed with a known molded semiconductor encapsulant in order to protect from external impact and moisture intrusion. You may. The curing of the molded semiconductor encapsulant may be carried out at the same time as the curing of the film-shaped semiconductor encapsulant, or may be carried out after the curing of the film-shaped semiconductor encapsulant.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.

表中の各成分は以下に示す通り。
熱硬化性成分
ＮＣ３０００：ビフェニルアラルキル型エポキシ樹脂、日本化薬株式会社製
ＹＤＰＮ－６３８：フェノールノボラック型エポキシ樹脂、新日鉄住金化学株式会社製
ＥＸＡ８３０－ＣＲＰ：ビスフェノールＦ型液状エポキシ樹脂、ＤＩＣ株式会社製
ＥＸＡ８５０－ＣＲＰ：ビスフェノールＡ型エポキシ樹脂、ＤＩＣ株式会社製
硬化剤
ＥＨ１０５：アミン系硬化剤、株式会社ＡＤＥＫＡ製
ＫＡ－１１８０：フェノール樹脂系硬化剤、ＤＩＣ株式会社製
硬化促進剤
２ＰＨＺ：イミダゾール系硬化促進剤、四国化成工業株式会社製
無機フィラー
Ｓｃｉｑａｓ（０．１μｍ）：シリカフィラー、平均粒径０．１μｍ、堺化学工業株式会社製
高分子樹脂
ｊＥＲ４２５０：ビスフェノールＡ／ビスフェノールＦ共重合型フェノキシ樹脂、三菱化学株式会社製
ＦＸ３１６：ビスフェノールＡ型フェノキシ樹脂、新日鉄住金化学株式会社製
フラックス剤
８－キノリノール：シグマアルドリッチジャパン合同会社製
エラストマー
ＸＥＲ－３２Ｃ：ブタジエン・アクリロニトリル・メタクリル酸共重合体、ＪＳＲ株式会社製
シランカップリング剤
ＫＢＭ５７３：信越化学株式会社製 (Examples 1 to 11, Comparative Examples 1 to 4)
A semiconductor wafer in which 16 semiconductor chips of 7.3 mm □ were connected was prepared. On each semiconductor chip surface, a protruding electrode having a structure in which a copper layer and a solder layer (Sn—Ag solder) are laminated in this order is provided. A film-shaped semiconductor encapsulant having the composition shown in the table below was cut into 4 cm □ and placed on the surface of the semiconductor wafer provided with the protruding electrodes, and placed on it. A film-shaped semiconductor encapsulant was laminated on a semiconductor wafer under the conditions shown in the table below using Kikai Seisakusho).

Each component in the table is as shown below.
Thermosetting ingredient
NC3000: Biphenyl aralkyl type epoxy resin, YDPN-638 manufactured by Nippon Kayaku Co., Ltd., EXA830-CRP: Bisphenol F type liquid epoxy resin manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., EXA850-CRP: Bisphenol manufactured by DIC Co., Ltd. A type epoxy resin, manufactured by DIC Co., Ltd.
Hardener
EH105: Amine-based curing agent, ADEKA Corporation KA-1180: Phenol resin-based curing agent, manufactured by DIC Corporation
Curing accelerator
2PHZ: Imidazole-based curing accelerator, manufactured by Shikoku Chemicals Corporation
Inorganic filler
Sciqas (0.1 μm): silica filler, average particle size 0.1 μm, manufactured by Sakai Chemical Industry Co., Ltd.
Polymer resin
jER4250: Bisphenol A / Bisphenol F copolymer type phenoxy resin, Mitsubishi Chemical Corporation FX316: Bisphenol A type phenoxy resin, manufactured by Nippon Steel & Sumitomo Metal Corporation
Flux agent
8-Kinolinol: Made by Sigma-Aldrich Japan GK
Elastomer
XER-32C: Butadiene / Acrylonitrile / Methacrylic acid copolymer, manufactured by JSR Corporation
Silane coupling agent
KBM573: Made by Shin-Etsu Chemical Co., Ltd.

The thickness of the film-shaped semiconductor encapsulant before cutting was measured by the following procedure, and the difference between the maximum height and the minimum height of the semiconductor encapsulant surface after laminating was measured by the following procedure.
Thickness of film-shaped semiconductor encapsulant
The film-like semiconductor encapsulant formed on the base film (PET film) is measured using a surface roughness / shape measuring machine (SURFCOM1500SD2, manufactured by Tokyo Seimitsu Co., Ltd.) with the surface of the base film as the reference height, and the thickness is measured. I asked.
Difference between the maximum height and the minimum height of the semiconductor encapsulant surface after laminating
The film-like semiconductor encapsulant laminated on the semiconductor chip (7.3 mm □) is scanned with a confocal microscope (Lasertec, OPTELICS H1200), unevenness is measured, and the film surface height is used as a reference. From the standard height, the highest point was set as the highest height, and the lowest point was set as the lowest height, and the difference between the two heights was calculated.
In Example 10, the back surface side of the semiconductor wafer was back grinded using abrasive grains (coarse (# 320), finish (# 2000)) of different sizes.
Next, for the semiconductor wafer laminated with the film-shaped semiconductor encapsulant, a dicing machine manufactured by Tokyo Seimitsu Co., Ltd. (model number: A-WD-100A) was used, and the speed was 20 mm / sec and the blade rotation speed was: along the dicing line. Dicing was performed under the condition of 30,000 rpm, and the chips were separated into predetermined sizes (7.3 mm × 7.3 mm) and used as test chips.
Then, a flip chip bonder (manufactured by Panasonic Factory Solutions Co., Ltd., trade name FCB3) was used to heat-press weld (TCB) the test chip and the silicon substrate. In Example 9, heat pressure welding (TCB) was carried out in the following procedure (b), and in the remaining Examples and Comparative Examples, heat pressure welding (TCB) was carried out in the following procedure (a).
Procedure (a)
After the test chip heated to 80 ° C. was brought into contact with the silicon substrate, the temperature was raised to 260 ° C. in that state to connect the protruding electrode of the test chip and the substrate electrode.
Procedure (b)
The test chip heated to 80 ° C. was mounted on a silicon substrate. Then, the heating head of the flip chip bonder heated to 300 ° C. was pressurized from above the mounted test chip, and the protrusion electrode of the test chip and the substrate electrode were connected.
Next, the film-shaped semiconductor encapsulant was heat-cured under a predetermined pressure atmosphere. Examples 1 to 7, 9, 10 and Comparative Examples 2 to 4 were heat-cured at 175 ° C. for 2 hours under a pressure atmosphere of 0.7 MPa. Example 8 was heat-cured at 175 ° C. for 2 hours under a pressure atmosphere of 0.4 MPa. Example 11 was heat-cured at 185 ° C. for 4 hours under a pressure atmosphere of 0.7 MPa. Comparative Example 1 was heat-cured at 175 ° C. for 2 hours under a pressure atmosphere of 0.3 MPa.
The above procedure was carried out at N = 5, and the following evaluation was carried out.
Visibility: During the alignment process with the flip-chip bonder, if no recognition error occurred at all of N = 5, it was evaluated as ◯, and if a recognition error occurred even with one test piece, it was evaluated as x.
Crawling up: The prepared test piece was visually observed. The case where the film-like semiconductor encapsulant was not observed to crawl up in all of N = 5 was evaluated as ◯, and the case where the film-like semiconductor encapsulant was observed to crawl up was evaluated as x.
Void: The prepared test piece was observed by a reflection method using an ultrasonic flaw detector (Scanning Acoustic Tomography, SAT). The case where no shadow / delamination shadow was observed on the image in all of N = 5 was marked with ◯, and the case where shadow was observed even with one test piece was marked with x.
Connection: Of the prepared test pieces, one test piece was taken out, and the peripheral portion was observed in a row in a cross section obtained by cutting out the connection cross section by polishing. Check with a scanning electron microscope whether there is solder wetting at the interface between the solder of the test chip and the pad of the Bottom chip. And said.

Examples 1 to 11 had good mountability (visibility, creeping up, voids, connection). It should be noted that Examples 2 and 3 are examples in which the thickness of the film-shaped semiconductor encapsulant, the height of the projection electrode of the semiconductor wafer, and the lamination pressure are changed from those of Example 1. Example 4 is an example in which the thickness of the film-shaped semiconductor encapsulant and the lamination pressure are changed with respect to Example 2. Example 5 is an example in which the thickness of the film-shaped semiconductor encapsulant is changed from that of Example 4. Examples 6 and 7 are examples in which the lamination pressure is changed with respect to Example 5. Example 8 is an example in which the pressure conditions at the time of curing of the film-shaped semiconductor encapsulant are changed from those of Example 5. Example 9 is an example in which the procedure of heat pressure welding (TCB) is changed from the procedure (a) to the procedure (b) with respect to the fifth embodiment. Example 10 is an example in which backgrinding is performed between lamination and dicing with respect to Example 5. In Example 11, the composition of the film-shaped semiconductor encapsulant was changed from composition A to composition B, and the curing conditions (temperature, heating time) of the film-shaped semiconductor encapsulant were changed with respect to Example 5. This is an example.
Comparative Example 1 was an example in which the film-shaped semiconductor encapsulant was cured in a pressurized atmosphere of less than 0.4 MPa (0.3 MPa), and the mountability (void) was x. Comparative Example 2 is an example in which the lamination pressure is more than 0.8 MPa (0.9 MPa) and the difference between the maximum height and the minimum height of the semiconductor encapsulant surface is more than 2.2 μm (2.3 μm). The sex (void) was x. In Comparative Example 3, the thickness of the film-shaped semiconductor encapsulant is less than 0.8 times the height of the protruding electrode (0.75), and the difference between the maximum height and the minimum height of the semiconductor encapsulant surface is 2. It was an example of more than 2 μm (2.3 μm), and the mountability (void) was ×. Comparative Example 4 was an example in which the thickness of the film-shaped semiconductor encapsulant was more than 1.3 times the height of the protruding electrode (1.40), and the mountability (crawling up) was ×. Therefore, the mountability (void, connection) was not evaluated.

Claims (5)

After laminating the film-shaped semiconductor encapsulant on the semiconductor chip on which the protruding electrode containing solder is formed, the film-shaped semiconductor encapsulant is heat-pressed against the substrate to connect the protruding electrode and the substrate electrode . Then, in the mounting method of the semiconductor device in which the film-shaped semiconductor encapsulant is heat-cured and the semiconductor chip is mounted on the substrate.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor chip is 2.2 μm or less.
The lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
A method for mounting a semiconductor device, wherein the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more. The film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, and the film-shaped semiconductor encapsulant is heat-pressed against the substrate to connect the protruding electrode and the substrate electrode . Then, in the mounting method of the semiconductor device in which the film-shaped semiconductor encapsulant is heat-cured and the semiconductor chip is mounted on the substrate.
The process of individualizing a semiconductor wafer laminated with the film-shaped semiconductor encapsulant.
A process of aligning an individualized semiconductor chip with the substrate electrode,
It has a step of pressure-welding the aligned semiconductor chip and the substrate while heating, and a step of heat-curing the film-shaped semiconductor encapsulant under a pressure atmosphere after the pressure welding.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor wafer and then separated into pieces is 2.2 μm or less.
The lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
A method for mounting a semiconductor device, wherein the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more. The film-shaped semiconductor encapsulant is laminated on a semiconductor wafer on which a protruding electrode containing solder is formed, and the film-shaped semiconductor encapsulant is heat-pressed against the substrate to connect the protruding electrode and the substrate electrode . Then, in the mounting method of the semiconductor device in which the film-shaped semiconductor encapsulant is heat-cured and the semiconductor chip is mounted on the substrate.
A step of reducing the thickness of a semiconductor wafer on which the film-shaped semiconductor encapsulant is laminated by polishing.
The process of individualizing a semiconductor wafer laminated with the film-shaped semiconductor encapsulant.
A process of aligning an individualized semiconductor chip with the substrate electrode,
The process of pressure-welding the aligned semiconductor chip and the substrate while heating, and
It has a step of heating and curing the film-like semiconductor encapsulant under a pressure atmosphere after pressure welding.
The thickness of the film-shaped semiconductor encapsulant is 0.8 times or more and 1.3 times or less the height of the protruding electrode.
The difference between the maximum height and the minimum height of the semiconductor encapsulant surface laminated on the semiconductor wafer and then separated into pieces is 2.2 μm or less.
The lamination pressure is 0.1 MPa or more and 0.8 MPa or less.
A method for mounting a semiconductor device, wherein the heat curing is carried out in a pressurized atmosphere of 0.4 MPa or more. The method for mounting a semiconductor device according to any one of claims 1 to 3, wherein the protruding electrodes have a structure in which a copper layer and a solder layer are laminated in this order on a semiconductor chip surface or a semiconductor wafer surface. The method for mounting a semiconductor device according to any one of claims 1 to 4, wherein the height of the protruding electrode is 5 μm or more and 50 μm or less.