JPH07161859A - Semiconductor device - Google Patents

Abstract

PURPOSE:To provide a semiconductor device which simplify the application process of a sealing without incurring the adhesion of foreign matter or damage of itself and improves the reliability by improving the sealing property. CONSTITUTION:In a semiconductor device where a glass lid 20 is bonded to a package through a sealing agent after a semiconductor chip is fixed inside the package, the adhesive face for the sealing agent of the glass lid is roughened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device such as a solid-state image pickup device and an EPROM in which a glass lid is adhered to an envelope, and more specifically, to a glass lid without causing foreign matter to adhere to or damage the glass lid. The present invention relates to a semiconductor device that simplifies the process of applying a sealant to a lid and improves the sealability to improve reliability.

[0002]

2. Description of the Related Art As a semiconductor device such as a solid-state image sensor and an EPROM, there is one as shown in FIG. That is,
This is an envelope in which a window frame 1a made of alumina and a base frame 1b are sandwiched by a lead frame 2 and bonded with a low melting point glass 11, and a bed portion 2b is formed at the center of the lead frame 2. This bed part 2b
A semiconductor chip (solid-state image sensor) 3 of a CCD image sensor is adhered to the central portion of the semiconductor chip 3 via a conductive adhesive layer 4, and a plurality of electrodes (not shown) formed on the inner surface of the semiconductor chip 3 And the inner lead at the tip of the lead 2a introduced from the side wall of the envelope 1 are connected by a bonding wire 5 of aluminum, gold or the like.

Further, a transparent glass lid 6 is hermetically adhered by a sealant 7 to the upper surface of the envelope 1, that is, the side on which light is introduced.

At the time of manufacturing a semiconductor device, the glass lid 6 is manufactured by a method using screen printing as shown in FIG. 6 or a method using baking as shown in FIG.
A sealant 7 is applied to the outer peripheral portion of the.

[0005]

In the method of screen printing shown in FIG. 6, a sealing agent 7 is placed on the screen 8 to be prepared, and the glass lid 6 is masked to cover a portion where the sealing agent is not applied. 9 is placed. As a result, the screen 8 descends and is pressed against the glass lid 6, and the sealant 7 is applied to the outer peripheral portion of the glass lid 6 except where the masking 9 is applied. Further, in this method, in order to secure a desired thickness of the sealant, the coating process using the screen 8 is repeated a plurality of times.

[0006] However, in this method, the coating process is complicated a plurality of times, and by repeating the coating a plurality of times, foreign matter from the masking 9 adheres to the portion of the glass lid 6 on which the masking 9 has been applied. Or, there was a problem that this part was damaged.

Next, in the method by baking shown in FIG.
As shown in FIG. 7A, on the outer peripheral portion of the glass lid 6,
Undercoat 10 using screen printing technique
Is applied, and the sealing agent 7a molded to have a desired thickness is placed and baked on it. As a result, the sealant 7a is applied to the outer peripheral portion of the glass lid 6. The reason for applying the undercoat is shown in FIG.
This is because, as shown in, when the sealing agent 7a is baked without applying the undercoat, the sealing agent 7a shrinks and the sealing agent 7a is not applied in a desired shape.

In this method, the sealing agent 7a need only be applied once, and the number of times of application itself can be small. However, since the undercoat 10 is applied by the screen printing technique, it is necessary to apply masking, and this masking causes a problem that foreign matter is attached to the glass lid 6 or the glass lid 6 is damaged. was there.

Further, when an organic sealant such as an epoxy resin is used as the sealant, moisture may enter from the interface of the organic seal, which may deteriorate the semiconductor chip. Therefore, in order to secure reliability as a semiconductor device, it is necessary to widen the seal width to which the sealant is applied.

The present invention has been made in view of the above-mentioned circumstances, and simplifies the step of applying a sealant and improves the sealing property without causing adhesion and damage of foreign matter. It is to provide a semiconductor device with improved reliability.

[0011]

To achieve this object, in a semiconductor device according to the present invention, after a semiconductor chip is fixed inside an envelope, a glass lid is bonded to the envelope via a sealant. The semiconductor device obtained by sealing the semiconductor chip is characterized in that the adhesive surface of the sealing agent of the glass lid is formed to be a rough surface.

[0012]

As described above, according to the present invention, the adhesive surface of the sealant of the glass lid is formed to be a rough surface, and high adhesiveness of the sealant is secured. Therefore, if the sealing agent is applied by the baking method, the undercoat can be eliminated and the masking step can be eliminated, thereby preventing foreign matter from adhering or being damaged due to the masking. In addition, by doing this, the number of times of application is only one,
The coating process can be simplified.

Further, since the adhesive surface of the glass lid sealant is formed to be rough, the adhesiveness can be improved and the reliability of the semiconductor device can be improved.
As a result of improving the reliability as described above, even if the seal width is shortened, the same reliability as the conventional one can be secured, and as a result, the semiconductor device can be downsized.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings. 1 is an exploded perspective view of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line [2]-[2] of FIG.

As shown in FIGS. 1 and 2, the outer peripheral portion 21 of the glass lid 20 bonded to the envelope of the semiconductor device is formed in a rough surface. The method of forming this rough surface will be described later. A glass lid 2 having this rough outer peripheral portion 21
0, for example, when the sealing agent is applied by a baking method, as shown in FIG. 1, the sealing agent 22 of the low melting point glass molded into a frame shape by press molding is applied to the outer peripheral portion 2 of the rough surface.
1 is placed on the outer peripheral portion 21 and baked.
It has been burned into. At this time, since the outer peripheral portion 21 is a rough surface, the sealing agent easily fits into the outer peripheral portion 21, and there is no contraction of the sealing agent as in the case where the mirror surface is directly baked as in the conventional case. No coat is needed. As a result, the step of masking the undercoat becomes unnecessary, and as a result, it is possible to prevent foreign matter from adhering or being damaged due to masking. Further, in this case, the number of times of applying the sealant 22 is only one, and the applying step can be simplified.

Further, the outer peripheral portion 2 of the rough surface according to the present embodiment.
The glass lid 20 having 1 is not particularly shown,
The sealing agent may be applied by a screen printing method. In this case, since the outer peripheral portion 21 of the adhesive surface is a rough surface, the wettability and the wet area are increased, and the characteristics as a sealant are improved. Not only low-melting-point glass but also organic adhesive such as epoxy resin is used as the sealing agent, because the outer peripheral portion 21 is roughened to increase the sealing area, that is, the sealing path. The characteristics are improved.

Next, a method for forming the rough surface of the glass lid 21 will be described with reference to FIGS. 3 (a), 3 (b), 3 (c) and 3 (d). In this method, the glass plate 23 is melted to form a rough surface. As shown in FIG. 3A, a pair of carbon molds 31, 32 is prepared, and one carbon mold 31 is prepared.
In order to form the outer peripheral portion 21 of the rough surface, a rough surface 21a corresponding to this is formed, a surface forming portion 33 corresponding to the mirror surface 24 of the glass lid 20 is formed, and a pair of carbon A wedge 34 for separating the lids 21 and 21 is formed. Because of this structure, it is passed through the furnace and melted in the state shown in FIG.
Thereby, as shown in FIG. 3B, the molten glass plate 23 enters the carbon mold 31 and is molded. As a result, as shown in FIG. 3C, the outer peripheral portion 21 of the rough surface of the glass lid 20 corresponds to the rough surface 21 a of the carbon die 31.
Is formed, a surface to be the mirror surface 24 of the lid 20 is formed corresponding to the surface forming portion 33 of the carbon die 31, and this surface is polished to be the mirror surface 24. At this time, the outer peripheral portion 2 of the rough surface
1 is formed to be one step lower than the mirror surface 24. Therefore, even after the glass plate 23 is separated by the wedge 34 as shown in FIG. 3D, the outer peripheral portion 21 of this rough surface is not polished and remains as a rough surface. The surface on the opposite side of the glass lid 20 is also polished to be a mirror surface 25.

Next, referring to FIG. 4, the glass lid 20
Another method for forming the rough surface will be described. In this other method, masking 9 is applied to the portions to be left as the mirror surface 24 and the mirror surface 25, and only the outer peripheral portion 21 is left unmasked. After that, the glass lid 20 is dipped in a glass-melting chemical such as fluorine. As a result, only the unmasked outer peripheral portion 21 is attacked by the chemicals and is formed as the roughened outer peripheral portion 21.

The present invention is not limited to the above-described embodiment, but can be variously modified.

[0020]

As described above, according to the present invention, the adhesive surface of the sealant of the glass lid is formed to be a rough surface, and high adhesiveness of the sealant is secured. Therefore, it is possible to prevent the adhesion of foreign matter and the occurrence of damage due to masking,
Further, in this case, the number of times of application is only one, and the application process can be simplified. Further, since the adhesive surface of the sealing agent of the glass lid is formed to be a rough surface, the adhesiveness can be improved and the reliability of the semiconductor device can be improved. As a result of improving the reliability as described above, even if the seal width is shortened, the same reliability as the conventional one can be secured, and as a result, the semiconductor device can be downsized.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line [2]-[2] of FIG.

3 (a), (b), (c), and (d) are respectively FIG.
FIG. 6 is a diagram showing a step of forming a rough surface on the glass lid shown in FIG.

FIG. 4 is a perspective view of a semiconductor device according to a modification of the invention.

FIG. 5 is a sectional view of a conventional semiconductor device.

FIG. 6 is a diagram showing a process of applying a sealant to a conventional semiconductor device by a screen printing method.

7A and 7B are diagrams showing a process of applying a sealant to a conventional semiconductor device by a baking method, respectively.

[Explanation of symbols]

 3 Semiconductor Chip 20 Glass Lid 21 Outer Part (Rough Surface) 22 Sealant

Claims (1)

[Claims] 1. A semiconductor device in which a semiconductor chip is fixed to the inside of an envelope, and then a glass lid is adhered to the envelope via a sealant to seal the semiconductor chip. The semiconductor device, wherein the adhesive surface of the sealing agent is formed to be rough.