JPH02232943A - Manufacture of resin molding - Google Patents

Abstract

PURPOSE:To make perfect a fixing of a circuit board by the rodlike protrusions of a die by a method wherein when the circuit board of a semiconductor device, such as IC card and the like, is buried in a plastic and the board and the plastic are integrally formed, part of the die is provided with a plurality of protrusions for fixing the circuit board in parallel with the direction of the connection of the semiconductor device of a molded body with other device. CONSTITUTION:A circuit board, such as an IC and the like, is built in an IC card, an electrode terminal 2 for external connection use is exposed near one end of a card base body 1 and groovelike opening parts 4 are provided in the back surface of the terminal 2 from one end of the card. Polypropylene film 6, which have a prescribed thickness and are subjected to surface roughening, are respectively tacked temporarily at parts where the circuit board 3 of this IC card comes into contact with press protrusions 4a for a top force 9 facing downward the terminal 2 and placed at prescribed positions on a bottom force 8, and in this state, the force 9 is clamped on the force 8. At this time, the board 3 is fixed to the protrusions 4a for the force 9 through the films 6 and each one end of the film 6 pinched in near parts of the force 9 which are suppressed by the protrusions 4a of the formed card is exposed at the base part of each opening part 6 and the board 3 is completely buried in an injection resin 5.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of embedding a circuit board of a thin semiconductor device such as an IC card in plastic and integrally molding the circuit board. [Prior art] The production of such resin molded bodies has conventionally been carried out using the method shown in Fig. 4 or 5.
This was done using the method shown in the figure. In the one shown in Figure 4,
After setting the circuit board 3 between the embankment-like protrusions 8a of the lower mold 8 and covering it with the upper mold 9, the portion of the circuit board 3 in contact with the lower mold 8 is depressurized from the decompression port 1O to remove the circuit board 3. was fixed in a mold, and then the resin 5 was injected from the injection port 8b and molded into one piece. Alternatively, as shown in FIG. 5, a part of the circuit board 3 is provided in the upper mold 9, and a spring
A bottle energized by! After pressing and fixing it to the lower mold 8 with l, resin 5 was injected from the injection port 8b and molded as one piece. In addition, in FIGS. 4 and 5, 7 is an IC mounted on the board 3. [Problems to be Solved by the Invention] However, in the method shown in FIG. 4, it is necessary to increase the area of the circuit board 3 in contact with the lower mold 8, and
The method shown in the figure requires a complicated mold structure in which the bottle 11 is movable and a spring 12 applies the necessary biasing force in order to absorb variations in the thickness of the circuit board 3. This invention was made to eliminate the above-mentioned drawbacks.
The aim is to obtain a resin molded body with good dimensional accuracy using a simple mold structure. [Means for Solving the Problems] A method for manufacturing a resin molded body according to the present invention includes a method for manufacturing a resin molded body in which a protrusion for fixing a circuit board is formed in a part of a mold so that a semiconductor device of the molded body is connected to another device. At the same time, a film-like resin is inserted between the circuit board and the protrusions, and when the mold is fastened, the film-like resin is deformed by the protrusions to absorb the thickness of the circuit board. To provide a molded article in which the parts of the circuit board pressed by the protrusions of the circuit board are not exposed. [Function] The method for manufacturing a resin molded body according to the present invention ensures that the circuit board is fixed in the mold by the fastening force of the mold and the so-called rod-shaped protrusions, and that The depression caused by the protrusion becomes a groove-like opening from one end of the molded object,
The film-like resin sandwiched between the circuit board and the circuit board is completely embedded in the molded body. In this way, the circuit board can be completely embedded in the resin of the molded body except for the external electrode terminal surface, which improves the reliability of the molded body against the external environment and prevents the circuit board from falling out of the molded body. Therefore, it is possible to obtain a molded body of a semiconductor device with a large degree of freedom in the design of the molded body. [Example] An example of the present invention will be explained below with reference to the drawings. FIG. 1 is a diagram showing the external shape of an IC card obtained by implementing the present invention.The IC card has an electrode terminal 2 for external connection exposed near one end of a card base 1, and one end of the card An opening 4 in the shape of a branch is provided from the top. The internal structure of this IC card is as shown in Figure 3 (a), (b), and (c). FIG. 3(a) is a partial cross-sectional view of one end of the terminal portion of the IC card viewed from the edge.
The opening extends parallel to the direction of the electrode terminal 2 and extends to one end of the IC card. Figure 3 (a) ``mouth'' is a cross-sectional view of the state viewed from the side. Figure 2 shows the state of this IC card when it is molded. FIG. 2(a) is a diagram of the electrode terminal of the IC card viewed from the side, and FIG. 2(b) is a diagram of the IC card as viewed from the electrode terminal side. First, place the circuit board 3 into the upper mold 9 with the electrode terminal surface facing down.
0.0. A roughened polypropylene film 6 with a thickness of 25 mm is temporarily fixed and placed in a predetermined position on the lower mold 8. In this state, the upper mold 9 is fastened. At this time, the circuit board 3 is fixed by the holding projections 4a of the upper mold 9 via the polypropylene film 6. In this state, the polypropylene film 6 as a whole is designed in such a dimensional relationship that the presser protrusion 4a slightly bites into it and deforms it. In this state, the thermoplastic resin 5 is injected through the injection port 8b by a normal method and integrally molded. The cross section of the molded IC card in the vicinity of where it was pressed by the pressing protrusion 4a is shown in Fig. 3 (a), (b), and (opening).
As shown in Figure 6, the sandwiched polypropylene film 6
A part of it is exposed at the bottom of the opening groove 4, and its end is completely buried in the injected resin 5. Figure 3《b》(a),《
In this example, instead of the polypropylene film 6, a polyester film 6a is pasted on the entire surface of the electrode terminal portion of the circuit board 3 on the part where the pressing protrusion 4a contacts. In FIG. 3(C) <<A), approximately 0.0% of the two-component polyurethane resin 6b is applied to the area where the presser protrusion 4a contacts. This is an example of coating 25m thick. As explained above using examples, the gist of the present invention is to absorb variations in the thickness of circuit boards (generally glass-based printed circuit boards) by deforming the film-like resin, and to directly attach the circuit board to the surface of the molded body. The electrode terminal for external connection is positioned at the predetermined position of the molded body by ensuring that the circuit board, etc. is not exposed, and when molding the molded body, securely fixes the circuit board, etc. at a predetermined position within the mold. It is something. Therefore, in the examples, polypropylene and polyester films were shown as application examples, but
The material is not particularly important, and the mold is used to fix a circuit board, etc. through a deformable plastic thin piece. [Effects of the Invention] As described above, the present invention is effective in embedding electrode terminals for external connection in a resin molded body except for the terminal surface of a circuit board or a terminal board on which an IC or the like is mounted. The substrate can be embedded in the mold by being held down by the protrusions of the mold through a thin plastic piece, and in this state, resin is injected into the mold and molded into a thin semiconductor device. This makes it possible to obtain a thin resin molded body with good dimensional accuracy, regardless of variations in the thickness of the substrate, etc.

[Brief explanation of the drawing]

Claims (1)

[Claims] In the production of semiconductor devices that incorporate integrated circuits such as ICs and expose external connection electrode terminals on the surface, the above-mentioned Production of a resin molded article characterized in that a film-like resin is sandwiched between the mold and the substrate when the substrate is fixed to the mold by pressing the surface of the substrate covered with the molded resin with the mold. Method.