JPH0745655A - Sealing structure of semiconductor element - Google Patents

Abstract

PURPOSE:To reduce the weight of the package when a TCP mounted on a TAB tape is sealed with a mold sealing material composed of a resin by using the transfer molding method. CONSTITUTION:Only the electrically connecting section between a semiconductor element 1 and external circuit is sealed with a resin by using the transfer molding method. After forming a TCP by jointing the element 1 to inner leads 4 on a TAB tape through bumps 3, a heat-resistant transparent resin, such as the silicone, etc., formed in a plate-like shape is stuck to a part to be opened on the circuit constituting surface of the element 1 with a ultraviolet curing bonding agent. After sticking, the connection between the element 1 and external circuit is sealed with the resin by using the transfer molding method. Then the plate-like resin is stripped off by reducing the adhesive strength of the bonding agent of the molded package by irradiating the bonding agent with ultraviolet rays. Or, only the electrically connecting section between the element 1 and external circuit and the active surface of the element 1 are sealed with the resin without opening by using the transfer molding method. Therefore, an UVEPROM, CCD, or optical, semiconductor element can be packaged in a TCP.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a container for semiconductor devices, and more particularly to a sealing structure for semiconductor devices in the form of a TAB system.

[0002]

2. Description of the Related Art Conventional TAB type mounting modes (hereinafter referred to as
Call it “TCP”. 3 is a sectional view of a semiconductor element sealing structure (hereinafter referred to as "package").

In FIG. 3, a circuit pattern is formed on the surface of a carrier tape 5 made of polyimide or the like with a conductive material such as copper to form a circuit board called "TAB tape". The portion 6 that connects the circuit pattern of the TAB tape to an external circuit is called an outer lead,
The portion 4 that connects the circuit pattern of the TAB tape and the semiconductor element is called an inner lead. The semiconductor device 1 is
Through the bumps 3 made of gold or the like for improving the electrical and mechanical bondability with the external circuit, the inner leads 4 of the TAB tape are collectively electrically connected together with other inner leads by thermocompression bonding called gang bonding. And TCP is obtained by mechanically joining. After that, in order to protect the connection portion and the semiconductor element, the outer leads are left and they are sealed by transfer molding with a mold sealing material 2 made of resin or the like to form a package. in this case,
The circuit configuration surface of the semiconductor element that needs to be protected (hereinafter,
Call it the "active surface". ) And the portion of the TAB tape other than the electrically joined portion with the inner lead, there is more sealing resin than necessary.

[0004]

However, due to the demand for light, thin, short, and small devices to be used, the semiconductor element is becoming highly integrated, and the outer shape of the semiconductor element is becoming larger, and the outer shape of the package is becoming larger than ever. Therefore, if a semiconductor element with a large outer shape is packaged as in the conventional case, the thickness of the semiconductor element is the same as in the conventional case, and the amount of mold resin used for sealing is large. Has a problem in that it becomes heavier in proportion to the size of the semiconductor element. In addition, a read-only memory that can be erased and rewritten with ultraviolet light (hereinafter, "U
VEPROM ") and charge coupled device (hereinafter referred to as" CC
D ". ) And the like, or a semiconductor element in which the optical junction of the optical semiconductor element cannot be molded and sealed, when TCP is used, there is a problem that packaging by transfer molding is difficult. It became a thing.

An object of the present invention is to reduce the weight of a package when TCP is sealed by a transfer mold using a mold encapsulant made of a resin, as compared with the prior art, and a semiconductor device such as UVEPROM or CCD. When a semiconductor element whose active surface is not mold-sealed is TCP, transfer molding enables packaging.

[0006]

The present invention adopts the following means in order to achieve the above object.

(Means 1) Only the electrical connection between the semiconductor element and the external circuit and the active surface are sealed with resin by transfer molding.

(Means 2) Only the electrical connection between the semiconductor element and the external circuit is sealed with resin by transfer molding.

[0009]

EXAMPLES Examples of the present invention will be described below with reference to FIGS.
This will be described with reference to FIGS. 5 and 6. TC based on (Means 1)
A sectional view of an example in which the present invention is applied to P is shown in FIG. As shown in FIG. 1, the inner lead 4 of the TAB tape and the semiconductor element 2 are joined together via the bump 3 by, for example, gang bonding to form a TCP. Next, the semiconductor element and TA
Only the joint portion of the inner lead of B and the active surface of the semiconductor element are resin-molded by transfer molding.
In the transfer mold, as shown in FIG. 6, a cavity called a cavity 10 formed by injecting a resin is provided on the dividing surface of a molding die 9 that can be divided into upper and lower parts or left and right parts. The semiconductor element 2 connected to the TAB to be sealed is sandwiched, the mold is closed, and resin is injected into the cavity and cured to form a package. According to the present invention, in order to prevent the portion of the semiconductor element to be sealed with resin from protruding outside the outer peripheral portion when the circuit configuration surface of the semiconductor element is a flat surface as shown in FIG. In the structure of the cavity 10 on the mold 9, the side surfaces of the cavity 10 and the semiconductor element 2 are formed such that the side surfaces of the cavity are separated by 10 μm or less so that the sealing resin does not enter. By fitting the semiconductor element into this cavity and molding the resin, only the connecting portion between the TAB tape and the semiconductor element and the active surface of the semiconductor element can be resin-sealed as shown in FIG.

An embodiment of the present invention by (means 2) will be described with reference to FIGS. 2, 4 and 5. 2 is a sectional view of an embodiment of the present invention, and FIGS. 4 and 5 are views showing an example of a manufacturing method of the embodiment of the present invention shown in FIG.

As shown in FIG. 4, the semiconductor element 1 and the TAB are
After bonding to the inner lead 4 of the tape via the bump 3 to form a TCP, a resin such as a heat-resistant transparent silicone is formed on a portion of the semiconductor element circuit configuration surface where an opening for exposure or the like is to be formed. 7 is formed into a plate shape so as to have the same thickness as the cross section to be sealed with resin when the circuit configuration surface of the semiconductor element is a flat surface, and is adhered by, for example, an ultraviolet curing adhesive 8. After that, resin sealing is performed by transfer molding as in the case of the means 1. Figure 5
The adhesive force of the adhesive is reduced by irradiating the adhesive 8 of the package after molding as shown in FIG.
Peels off. The package as shown in FIG. 2 is completed by the above method.

[0012]

According to the present invention, as compared with the conventional TCP, the volume occupied by the sealing resin 2 is shown in FIG.
The volume can be suppressed to about 20% of the volume of the sealing resin 2 and the TCP can be reduced in weight and size. In addition, elements such as UVEPROMs, CCDs, and optical semiconductor elements that have functions of receiving and emitting light, which have been difficult to form by transfer mold TCP, can be formed into TCP, and the linear expansion coefficient of the semiconductor element and the sealing resin can be reduced. There is an effect that the package does not warp due to the difference. Further, compared with the conventional manufacturing process, only the shape of the molding die used in the transfer molding process is different, and there is an effect that the production process in implementing the present invention is significantly less affected. .

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment according to means 1 of the present invention.

FIG. 2 is a sectional view of an embodiment based on means 2 of the present invention.

FIG. 3 is a sectional view of a conventional TCP.

FIG. 4 is a cross-sectional view showing the forming process of an embodiment based on means 2 of the present invention.

FIG. 5 is a cross-sectional view showing the forming process of one embodiment based on means 2 of the present invention.

FIG. 6 is a cross-sectional view showing the forming process of one embodiment based on means 1 of the present invention.

[Explanation of symbols]

 1 Semiconductor Element 2 Sealing Resin 3 Bump 4 Inner Lead 5 Carrier Tape 6 Outer Lead 7 Heat-Resistant Resin 8 UV-Curing Adhesive 9 Mold Die 10 Cavity

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Claims (2)

[Claims] 1. A method of encapsulating a semiconductor element in a TAB mounting form, which is transfer-molded with a molding encapsulant made of a resin or the like only on an electrical joint between the semiconductor element and an external circuit and a circuit configuration surface. A sealing structure for a semiconductor element, characterized in that: 2. A method of encapsulating a semiconductor element having a TAB mounting structure, wherein transfer molding is performed only on an electrical junction between the semiconductor element and an external circuit with a mold encapsulating material made of resin or the like. Characteristic semiconductor element sealing structure.