JP2001351945A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which a semiconductor device which has resistance to changeover aging can be manufactured through a simple process, in order to solve the problem of the change of the connection resistance between a semiconductor and metal balls caused by changeover when a semiconductor is connected electrically to metal balls, by bringing the semiconductor into contact with the balls at the time of mounting the semiconductor using an anisotropic conductive resin. SOLUTION: By making a film of a thermosetting resin 1 formed on a wiring board 5 carrying solder bumps 4 formed on be a surface and a semiconductor element 2 mounted on the board 5 by melting the solder bumps 4 heating, and then the element 2 is fixed on the board 5 through curing the resin 1, not only electrical connection and resin encapsulation can be made at the same time, but also accordingly the process can be simplified. In addition, since the electrical connection is obtained by a metallic bond by soldering, the change in the connection resistance due to changeover aging can be reduced significantly and a high reliability semiconductor device can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device in which a package is formed by using a solder bump and a thermosetting resin material.

[0002]

2. Description of the Related Art In recent years, demand for semiconductor devices has rapidly increased with the rapid development of small portable devices. Accordingly, there has been a demand for a method of manufacturing a semiconductor device which is advantageous at low cost and suitable for mass production. As a manufacturing method for realizing the demand, there has been proposed a method using an anisotropic conductive resin in which metal balls such as Ni and Au are dispersed in a thermosetting resin.

In this manufacturing process, as shown in FIG. 3, a layer of an anisotropic conductive resin 10 is formed on a wiring substrate (step a), and the semiconductor element 2 is aligned with the pattern of the wiring substrate 5 and mounted ( Step b), heating and pressurizing from above the semiconductor element 2 (step c).

[0004] This method can be said to be a low-cost and advantageous method for mass production because the resin sealing step for improving the electrical connection and reliability between the semiconductor element 2 and the wiring board 5 can be performed at once. In this case, electrical conduction between the semiconductor element 2 and the wiring board 5 is obtained by the metal balls 11 in the anisotropic conductive resin 10.

[0005]

However, in the semiconductor device fabricated by this method, the electrical connection between the semiconductor element and the wiring board is made by contacting the metal ball, so that the connection resistance value is changed by aging. There was a problem of fluctuation.

Accordingly, the present invention provides a semiconductor device in which electrical connection between a semiconductor element and a wiring board can be performed by metal bonding, and a resin sealing step for improving electrical connection and reliability between the semiconductor element and the wiring board can be performed at once. It is intended to provide a method of manufacturing the device.

[0007]

According to the present invention, there is provided a method of manufacturing a semiconductor device, comprising: connecting a semiconductor element to a wiring board via solder bumps; Forming a solder bump on a semiconductor element or a wiring board, forming a film of a thermosetting resin on the semiconductor element connection surface side of the wiring board, and forming the semiconductor element on the wiring board via the thermosetting resin. Is mounted, and while the solder bumps are heated and melted to obtain an electrical connection between the semiconductor element and the wiring board, the thermosetting resin is also heated and cured to fix the semiconductor element on the wiring board. It is characterized by doing. According to the present invention, the electrical connection between the semiconductor element and the wiring board is obtained by metal bonding using solder, so that a change in connection resistance due to aging can be significantly reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention relates to a method of manufacturing a semiconductor device in which a semiconductor element and a wiring board are electrically connected via solder bumps. Forming a solder bump, forming a film of a thermosetting resin on the semiconductor element connection surface side of the wiring board, mounting the semiconductor element on the wiring board via the thermosetting resin, While simultaneously heating and melting to obtain the electrical connection between the semiconductor element and the wiring board, the thermosetting resin is also heated and cured to fix the semiconductor element on the wiring board, Since the electrical connection between the semiconductor element and the wiring board and the resin encapsulation are performed simultaneously, the process can be simplified, and the electrical connection between the semiconductor element and the wiring board can be obtained by metal bonding using solder. The connection resistance value variation by reduction greatly reduced, it is possible to realize a highly reliable semiconductor device.

According to a second aspect of the present invention, there is provided a method of manufacturing a semiconductor device according to the first aspect, wherein a solder bump is formed on a wiring board and a semiconductor element is heated on the wiring board. Since the semiconductor device is mounted and heating is performed at the same time as mounting the semiconductor element, the manufacturing time can be further reduced as compared with the method according to the first aspect.

According to a third aspect of the present invention, there is provided the method of manufacturing a semiconductor device according to the second aspect, wherein the thermosetting resin is formed thinner than the height of the solder bump. Since the solder bump in contact with the previously heated semiconductor element is melted to electrically connect the semiconductor element and the wiring board, and then the curing reaction of the thermosetting resin starts,
Conduction failure due to curing of the thermosetting resin before the electrical connection between the semiconductor element and the wiring board hardly occurs.

According to a fourth aspect of the present invention, there is provided the method of manufacturing a semiconductor device according to the third aspect, wherein the wiring board is cooled until the semiconductor element and the wiring board are electrically connected. By cutting off the cooling operation to the wiring substrate side, the thermosetting resin is completely cured, and in an uncured state of the thermosetting resin, the electrical connection between the semiconductor element and the wiring substrate can be performed. No conduction failure occurs.

According to a fifth aspect of the present invention, there is provided the method for manufacturing a semiconductor device according to the first aspect, wherein a thermosetting resin having a curing temperature characteristic higher than a melting temperature of the solder bump is used. The solder bumps melt first to make electrical connection with the wiring board, and then the curing reaction of the thermosetting resin starts, so thermosetting before the electrical connection between the semiconductor element and the wiring board The conduction failure due to the hardening of the conductive resin does not occur.

According to a sixth aspect of the present invention, there is provided the method of manufacturing a semiconductor device according to the first aspect, wherein the surface of the solder bump is plated with gold. Poor connection can be prevented.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
FIG. 6 is a cross-sectional view showing the method for manufacturing the semiconductor device in FIG. In FIG. 1, 1 is a thermosetting resin, 2 is a semiconductor element, 3 is an input / output terminal, 4 is a solder bump, 5 is a wiring board, and 6 is a wiring pattern.

As shown in FIG. 1, in the method of manufacturing a semiconductor device according to the present embodiment, a solder bump 4 is formed on a semiconductor element 2 (step a), and a layer of a thermosetting resin 1 is formed on a wiring board 5. After forming (step b), the semiconductor element 2 is mounted on the wiring board 5 via the thermosetting resin 1 (step c), and the solder bumps 4 and the thermosetting resin 1 are heated and pressurized, thereby forming the semiconductor element. 2 and the wiring board 5 are electrically connected via the solder bumps 4, and the resin sealing is performed by curing the thermosetting resin 1 (step d).

As the thermosetting resin 1, a paste or a filter is used. In this case, since the electrical connection and the resin sealing are performed at the same time, not only the process is simplified, but also the electrical connection is obtained by the metal bonding of the solder bumps. Semiconductor device can be realized.

In this embodiment, the configuration in which the solder bumps are formed on the semiconductor element side has been described. However, the same effects can be obtained by forming them on the wiring board side.

In this embodiment, the solder bumps and the thermosetting resin are heated from above the semiconductor element. However, the same applies when the solder bumps and the thermosetting resin are heated from the substrate side or exposed to a high-temperature atmosphere. The effect of is obtained.

(Embodiment 2) FIG. 2 shows Embodiment 2 of the present invention.
FIG. 6 is a cross-sectional view showing the method for manufacturing the semiconductor device in FIG.

As shown in FIG. 2, in the method of manufacturing a semiconductor device according to the present embodiment, the solder bumps 4 are formed on the wiring board 5 (step a), and the surface of the wiring board 5 on which the solder bumps 4 are formed is thermoset. The layer of the conductive resin 1 is formed thinner than the height of the solder bumps 4 (step b), and the semiconductor element 2 is mounted on the surface of the wiring board 5 on which the thermosetting resin 1 is formed while heating. First, the top of the protruding solder bump 4 contacts the heated semiconductor element 2, the solder bump 4 melts and is connected to the input / output terminal 3 of the semiconductor element 2. The heated semiconductor element 2 comes into contact, the curing reaction of the thermosetting resin 1 proceeds, and the semiconductor element 2 is sealed and fixed (step c).

As the thermosetting resin 1, a paste-like resin is used. In this case, there is no problem that the thermosetting resin undergoes a hardening reaction before the solder bumps are melted and connected to the semiconductor element, resulting in poor conduction.
Also, when mounting the semiconductor element, by cooling the substrate side until the semiconductor element and the solder bumps are electrically connected, by delaying the curing reaction timing of the thermosetting resin,
Further reliable conduction can be obtained. In particular, when a highly reactive thermosetting resin is used, this method is effective.

(Embodiment 3) A method of manufacturing a semiconductor device according to the present embodiment is the same as that of the first embodiment. The feature here is that a material having a curing temperature characteristic higher than the melting temperature of the solder bump is used for the thermosetting resin to be used. This eliminates the problem that the thermosetting resin is hardened before the solder bumps are melted, resulting in poor conduction.

(Fourth Embodiment) A method of manufacturing a semiconductor device according to the present embodiment is the same as that of the first embodiment. The feature here is that gold plating is applied to the solder bumps. This can prevent connection failure due to oxidation of the solder bumps.

[0025]

As described above, in the method of manufacturing a semiconductor device according to the present invention, a thermosetting resin serving as a sealing resin at the same time as electrically connecting a semiconductor element to a wiring board while melting solder bumps. In addition to the hardening, the process can be simplified and the method is advantageous in mass production at low cost.In addition, since the electrical connection between the semiconductor element and the wiring board is obtained by metal bonding with solder, the connection resistance value due to aging Variations can be significantly reduced, and a highly reliable semiconductor device can be realized.

[Brief description of the drawings]

FIG. 1 is a process sectional view illustrating a method for manufacturing a semiconductor device according to a first embodiment of the present invention;

FIG. 2 is a process sectional view illustrating the method for manufacturing the semiconductor device in the second embodiment of the present invention.

FIG. 3 is a process sectional view showing a conventional method for manufacturing a semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thermosetting resin 2 Semiconductor element 3 I / O terminal 4 Solder bump 5 Wiring board 6 Wiring pattern

Continued on the front page (72) Inventor Takeo Abo 1006 Kadoma, Kazuma, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 5F044 KK08 KK16 LL04 LL11 QQ01 RR17 RR18 RR19 5F061 AA01 BA04 CA10 CB02

Claims (6)

[Claims] In a method of manufacturing a semiconductor device, wherein a semiconductor element and a wiring board are electrically connected via a solder bump, a solder bump is formed on the semiconductor element or the wiring board.
A film of a thermosetting resin is formed on the semiconductor element connection surface side of the wiring board, the semiconductor element is mounted on the wiring board via the thermosetting resin, and the solder bumps are heated and melted. A method of manufacturing the semiconductor device, wherein the thermosetting resin is heated and cured while the electrical connection between the semiconductor element and the wiring substrate is obtained, thereby fixing the semiconductor element on the wiring substrate. 2. The method according to claim 1, wherein solder bumps are formed on a wiring board, and the semiconductor elements are mounted on the wiring board while heating. 3. The method according to claim 2, wherein the thermosetting resin is formed thinner than the height of the solder bump. 4. The method according to claim 1, wherein the wiring board is cooled until the semiconductor element is electrically connected to the wiring board, and then the cooling operation to the wiring board is stopped to completely cure the thermosetting resin. The method for manufacturing a semiconductor device according to claim 3. 5. The method for manufacturing a semiconductor device according to claim 1, wherein a thermosetting resin having a curing temperature characteristic higher than a melting temperature of the solder bump is used. 6. The method according to claim 1, wherein a surface of the solder bump is plated with gold.