JPH10326800A - Manufacture of semiconductor device and mold for semiconductor manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the warping of a plastic package, practically, such a package that is formed by sealing one surface of a substrate, such as the BGA, etc., with a resin caused by the difference in coefficient of thermal contraction of the package. SOLUTION: A substrate is warped in advance in the direction opposite to the warping direction of the package before the substrate is sealed with a resin 8. In a mold (first mold) 1 a recessed section (cavity) 3 for enclosing the resin 8 and the flowing passage (runner) 4 for resin communicated with the cavity 3 are provided. In another mold (second mold) 2, a convex part 5 is provided at the position where the center of the convex part 5 comes to the center of the cavity 3 when the molds 1 and 2 are put together. A substrate 7 mounted with a semiconductor 6 is set in the mold 1 with the semiconductor 6 on the down side so that the semiconductor 6 may come to the center of the cavity 3. Therefore, the substrate 7 is curved by means of the convex part of the mold 2 and, while the substrate 7 is curved, the cavity 3 is filled up with the resin 8 through the runner 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing a package from being warped after a plastic package is sealed with a resin, and a manufacturing apparatus for preventing the warpage. The present invention relates to a semiconductor manufacturing method and a manufacturing apparatus suitable for a plastic package to be sealed.

[0002]

2. Description of the Related Art Conventionally, a resin encapsulation process of a plastic package involves forming a package called a cavity by sandwiching a substrate on which a semiconductor is mounted between upper and lower molds heated to about 150 ° C. to 200 ° C. In the process of taking out the resin-filled substrate after opening the mold after the resin is sealed in the cavity provided in the mold through a resin inflow path called a runner and curing by a certain degree of heat has progressed. However, at this time, the substrate on which the semiconductor was mounted was flat and sandwiched between molds.

[0003]

After the resin is sealed and the package is formed, when the package temperature falls to room temperature, the difference in the heat shrinkage between the sealed resin and the substrate causes the difference.
The package warps. In general, the heat shrinkage of a resin for forming a package containing silica particles as a main component is larger than the heat shrinkage of a material used for a substrate, for example, glass epoxy, BT resin, polyimide, etc. The package is bent so that the central portion on the substrate surface side is convex.

When the package is warped as described above,
When a package is mounted on a substrate, the connection terminals of the package may not uniformly contact the connection lands provided on the substrate, resulting in a mounting failure.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device, wherein an external terminal is formed on one surface of a circuit board. A method for manufacturing a semiconductor device in which a semiconductor chip is mounted on the other surface side of the circuit board and the semiconductor chip is sealed with a plastic resin, wherein the semiconductor chip is sealed with the plastic resin In the step, sealing is performed in a state where the substrate on which the semiconductor chip is mounted is curved.

According to a second aspect of the present invention, in addition to the method of the first aspect, the circuit board is formed of the plastic resin in a state where the circuit board is curved to a side opposite to a side on which the semiconductor chip is mounted. Sealing is performed. That is, in order to improve the warpage of the package due to the difference in the thermal shrinkage between the substrate and the resin, the substrate is characterized in that the substrate is warped in the direction opposite to the warping direction after the package is completed before sealing the resin.

According to a third aspect of the present invention, an external terminal is formed on one surface of a circuit board and the other surface of the circuit board is formed on the other surface of the circuit board. A semiconductor chip is mounted, the semiconductor chip is a mold for a semiconductor manufacturing apparatus for sealing with a plastic resin, and is located on a surface side of the circuit board on which the semiconductor chip is mounted, and the semiconductor chip is A first mold in which a concave portion into which resin is injected is formed, and a convex shape is formed at a position in contact with the surface of the circuit board on a surface side of the circuit board opposite to a surface on which the semiconductor chip is mounted. And a second mold provided with the second mold. In other words, here, as means for warping the substrate, a convex shape is added to a portion in contact with a portion of the mold that warps the substrate, and when the substrate is sandwiched between the upper and lower molds, the convex portion of the mold pushes the substrate. As a result, the substrate is warped. The convex shape of the mold is preferably a shape in which no gap is formed between the substrate and the mold when the substrate is warped, since the heat of the mold is most easily transmitted to the substrate, but it may be supported at one point like an ejector pin. Absent. The location where the warp is greatest is located at the center of the package.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a state in which a substrate on which a semiconductor is mounted is mounted on a mold used for resin sealing, and FIG. 2 is a cross-sectional view of a state in which the substrate on which the semiconductor is mounted is sandwiched between upper and lower dies. Drawing 3 is a drawing showing the package immediately after resin encapsulation,
FIG. 4 is a drawing showing the package when it has been cooled to room temperature.

First, a semiconductor manufacturing apparatus for resin encapsulation will be described with reference to FIG. The apparatus used for resin sealing is composed of a mold 1 and a mold 2 heated to about 150 ° C. to 200 ° C. The mold 1 (first mold) is provided with a cavity 3 (hereinafter referred to as a cavity) for enclosing the resin, and a resin flow path 4 (hereinafter referred to as a runner) leading to the cavity 3.

The mold 2 (second mold) is provided with a convex shape 5 which is a feature of the present invention.
When the two are superimposed, the center of the two is located at the center of the cavity 3 of the mold 1.

The substrate 7 on which the semiconductor 6 is mounted is set in the mold 1 with the semiconductor 6 facing downward so that the semiconductor 6 is at the center of the cavity 3.

FIG. 2 shows that after the substrate 7 is set in the mold 1,
The figure shows a state where the resin is sandwiched by the mold 2 to fill the resin.

The substrate 7 is curved by the convex shape 5 provided on the mold 2, and the resin 8 is filled into the cavity 3 through the runner 4.

FIG. 3 shows the package 9 immediately after resin sealing. The package is curved by the convex shape 5 of the mold 2 so that the central portion on the substrate side is concave.

FIG. 4 shows a state where the temperature of the package 9 has been lowered to room temperature. The curvature of the package is corrected by the difference in the thermal shrinkage between the resin 8 and the substrate 7 constituting the package 9, and as a result, the package 9 has a flat shape.
Thereafter, when solder balls are mounted on the substrate 7, a package of a ball grid array is completed.

[0017]

According to the present invention, the warpage due to the difference in the thermal shrinkage of the plastic package having one side of the substrate resin-sealed can be improved and the package can be mounted smoothly when mounted on the substrate.

[Brief description of the drawings]

FIG. 1 is a diagram in which a substrate on which a semiconductor is mounted is placed on a mold used for resin sealing.

FIG. 2 is a diagram in which the mold of FIG. 1 is clamped for resin sealing.

FIG. 3 is a view showing a plastic package immediately after resin sealing by the apparatus and method of FIG. 1;

FIG. 4 is a diagram showing a state in which the package of FIG. 3 has cooled to room temperature.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Die (lower die) 2 ... Die (upper die) 3 ... Cavity 4 ... Runner 5 ... Convex shape 6 ... Semiconductor 7 ... Substrate 8 ...・ Resin 9 ・ ・ ・ Plastic package

Claims (3)

[Claims] An external terminal is formed on one side of a circuit board, a semiconductor chip is mounted on the other side of the circuit board, and the semiconductor chip is sealed with a plastic resin. A method of manufacturing a semiconductor device, wherein in the step of sealing the semiconductor chip with the plastic resin, sealing is performed in a state where a substrate on which the semiconductor chip is mounted is curved. 2. The method according to claim 1, wherein said circuit board is sealed with said plastic resin in a state where said circuit board is curved to a surface opposite to a surface on which said semiconductor chip is mounted.
The manufacturing method of the semiconductor device described in the above. 3. A semiconductor manufacturing method in which external terminals are formed on one side of a circuit board, a semiconductor chip is mounted on the other side of the circuit board, and the semiconductor chip is sealed with a plastic resin. An apparatus mold, which is located on a side of the circuit board on which the semiconductor chip is mounted,
A first mold including the semiconductor chip and having a recess into which resin is injected, and a surface of the circuit board facing the surface of the circuit board on a surface side opposite to a surface on which the semiconductor chip is mounted; The second having a convex shape at the position
A mold for a semiconductor manufacturing apparatus, comprising: a mold;