JPS62136052A - Semiconductor device - Google Patents

Abstract

PURPOSE:To contrive to be low in cost to improve damp-proof property, by sealing an IC chip with resin and installing a window member above the IC chip to coat the side part of the window member with an adhesive. CONSTITUTION:Above an IC chip 11 formed of ROM die-mounted on a stage 12 of a lead frame, a window member 17, having the nearly same sectional area as the area of the IC chip, is installed. The window member 17 is made of a transmitting material such as ceramics. Side planes except upper and lower surfaces of the window material 17 are coated with an adhesive 18, such as polyimide, superior in adhesiveness, in order to improve adhesiveness between sealing resin 16 and the window member 17. A transmitting thin film 15 for protecting the IC chip 11, when resinous sealing being performed, is formed of silicone resin on the surface of the IC chip 11. Thus, a large decrease in cost is available, and the package sealed with resin becomes superior in damp- proof property.

Description

[Detailed Description of the Invention] [Summary] A resin material with excellent adhesion is coated on the side surface of a window material (
This is a plastic Er'ROM characterized by improved moisture resistance.

[Industrial application field]

The present invention relates to a semiconductor device, and more specifically, instead of a conventional ceramic EPROM (erasable/writable read-only memory), an EFROM is sealed with resin, and a window material that allows ultraviolet rays to pass is placed above the ROM. The present invention relates to an EFROM package having a structure in which the side surface of the window material is coated with a resin material having excellent adhesiveness and moisture resistance.

[Conventional technology]

The ceramic type EFROM package shown in the cross-sectional view of FIG. 4 is known, and in the same figure, 31 is 1
70M is formed IC chip, 32 is ceramic body, 33 is ceramic cap, 34 is camp 33
35 is a glass seal, 36 is a metallized layer, and 37 is a lead, the ICC lamp 1 is irradiated with light 38 through the glass window 34 to erase the memory formed in the IC tube 31, and Make a note.

[Problem that the invention seeks to solve]

The ceramic body 32 is formed by laminating and sintering ceramic green sheets, which has the problem of requiring a large number of steps and significantly increasing costs.

Therefore, it was proposed to form an EFROM package by resin sealing, and a structure shown in the cross-sectional view of FIG. 5 was proposed. In addition, in FIG. 5, 41 is a ROM
42 is a sealing resin such as epoxy resin, 43 is a ceramic window material, and 44 is a lead. Light 45 is irradiated through the ceramic window material 43 to erase and write in the ROM.

In such a structure, the adhesion between the ceramic window material 43 and the sealing resin (for example, epoxy resin) 42 is poor, and
The ceramic window material 43 has a different coefficient of thermal expansion.
There is a problem that a gap is formed between the contact surface of the epoxy resin 42 and the epoxy resin 42, and water and moisture enter from the gap, that is, the moisture resistance is poor.

The present invention was created in view of these points, and an object of the present invention is to provide an EFROM that is low in cost and has excellent moisture resistance.

[Means for solving problems]

FIG. 1 is a sectional view of an embodiment of the present invention, and in the same figure, 11
12 is the IC chip on which 120M is formed, 12 is the stage of the lead frame to which the IC chip 11 is attached, 13
14 is a lead, 14 is a wire connecting the electrode lead 13 of the IC chip 11, and 15 is a material coated on the IC chip 11, such as silicone resin, which has a property of transmitting ultraviolet rays (hereinafter referred to as translucency) and elasticity. 16 is a sealing resin such as epoxy resin, 17 is a transparent window material made of alumina, and 18 is a coating on the side surfaces of the window material 17 except for the upper and lower surfaces as seen in the figure. It is an adhesive material such as polyimide that has excellent adhesion.

In the embodiment shown in FIG. 1, an EFROM pancase in which an IC chip 11 is sealed with resin is provided. 18 is coated.

[Effect]

In the EFROM package having the above structure, the window material 1
7 is bonded to the epoxy resin 16 with adhesive 18 with good adhesion, so that external water and moisture are prevented from entering the package through the contact surface between the two, and RO
Light for erasing and writing M is irradiated onto the IC chip 11 through the transparent window material 17 and the transparent thin film 15.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

Thinning Referring to Figure 1, stage 1 of the lead frame
The IC chip 11 with the ROM formed thereon is sealed with, for example, an epoxy resin 16.
Unlike the conventional plastic type package in which the IC chip is completely sealed with resin, a window material 17 having a cross-sectional area approximately the same size as the area of the IC chip is arranged above the IC chip 11. The window material 17 is made of a translucent material such as ceramic. In order to improve the adhesion between the sealing resin 16 and the window material 17, that is, to prevent external moisture from entering through the contact surface between the two, the window material 17 is An adhesive material 18 with good adhesion, such as polyimide, is coated on the side surfaces of the window material 17 and the adhesive material 18, but the materials for the window material 17 and the adhesive material 18 are not limited to those mentioned above.

The window material 17 has the shape shown in the perspective view of FIG. 2, and its side surfaces are coated with an adhesive 18.

The window material 17 is dimensioned so that the extent of the surface not coated with the adhesive 18 almost covers the upper surface of the IC chip 11 .

A transparent thin film 15 made of, for example, silicone resin is formed on the surface of the IC chip 11 to protect the IC chip 11 during resin sealing. This thin film 15 is applied so as to completely cover the surface of the IC chip 11.

Fig. fiIJ3 is a cross-sectional view showing in detail the state in which the transparent thin film 15 is coated, and in this figure, lla indicates the cell portion of the IC chip. Since the wire 14 has already been bonded to the electrode of the IC chip, there is no problem in covering the bonded portion of the wire with silicone resin. In the illustrated example, the height of the ball-shaped adhesive portion 14a of the wire is 50 mm, the thickness of the IC chip 11 is 400 to 500 μm, and the thickness of the silicone resin is approximately 100 to 200 μm. The transparent thin film 15 may be formed of an elastic, transparent gel-like resin other than silicone resin.

The pan cage shown in Figure 1 is IC chip attachment/wire attachment silicone resin coating Attach window, cure and fix mold forming window installation It can be made by the process of

The light-transmitting thin film functions to protect the IC chip 11 during the above-described molding. For molding/forming, a normal metal mold can be used.

〔Effect of the invention〕

As described above, according to the present invention, the EFROM package is formed by resin sealing instead of the conventional expensive ceramic package, and the cost is reduced to 1/20 to 1/1.
In addition, the resin-sealed package has excellent moisture resistance.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of the window material of the device shown in FIG. 1, FIG. 3 is a cross-sectional view showing a part of the device shown in FIG. 1 in detail, and FIG. is a sectional view of a conventional example, and FIG. 5 is a sectional view of another conventional example. In Figures 1 to 3, 11 is an IC chip, 11a is a cell part of a C chip, 12 is a stage of a lead frame, 13 is a lead, 14 is a wire, 14a is an adhesive part of the wire, 15 is a translucent part 16 is an epoxy resin (sealing resin), 16a is an inner wall, 17 is a window material, 18 is an adhesive, 21a is a lower mold, 21b is an upper mold, 22 is a lead frame, 23 is a protrusion of the upper mold .Representative Patent attorney: Hajime Kuki Agent: Patent attorney Yoshiyoshi Osuga Figure 3 of the latter 9J nail resistance diagram of the former example #r surface Figure 5

Claims (1)

[Claims] An IC in which an erasable/writable read-only memory is formed.
The chip (11) is sealed with a resin into a plastic type package, and the surface of the IC chip (11) is provided with an elastic thin film (15) that transmits ultraviolet rays, and above the IC chip (11) is provided with an elastic thin film (15). A semiconductor device characterized in that a window material (17) having approximately the same area as the area of the window material (17) is arranged, and the side surface of the window material (17) is coated with an adhesive material (18) having adhesive properties.