JPH06252281A - Cap for semiconductor device and its manufacture - Google Patents

Abstract

PURPOSE:To absorb reflected light and prevent stray light, by forming a corrosion-resistant base plating film on a cap main body, and forming a cobalt or cobalt alloy plating film so as to be almost black on the corrosion resistant base plating film. CONSTITUTION:A transmission hole 22 is formed on the upper surface of the cap main body 21, and a corrosion resistant base plating film 23 is formed on the surface of the transmission hole 22. A cobalt or cobalt alloy plating film 24 is formed on the film 23. By fusing low melting point glass 25, a light transmission window body 26 composed of rigid glass is fixed so as to cover the transmission hole 22. By heat treatment for about 30 minutes, the cobalt or cobalt alloy plating film 24 is oxidized to form a black oxide film. Thereby generation of stray light is prevented to the utmost, and malfunction can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device cap and a method of manufacturing the cap.

[0002]

2. Description of the Related Art A light emitting and receiving device for an LD (laser disk) is inevitably required to be downsized as home electric appliances and the like into which it is incorporated are downsized. FIG. 3 shows the above-mentioned light projecting / receiving device, in which a laser device 11 for projecting light and a laser device 12 for receiving light are mounted at required portions of the stem 10.
These elements are hermetically sealed by a cap 14 having a light transmitting window 13 made of hard glass or the like. Reference numeral 15 is a monitor element corresponding to the laser elements 11 and 12.
The light transmitting window body 13 is welded by a low melting point glass 16 covering the through hole 18 of the cap body 17. Reference numeral 19 is a hologram glass.

[0003]

Conventionally, these devices have been
Although the light-transmitting device and the light-receiving device were separately provided, in recent years, a device for both light-transmitting and light-receiving has been developed in which an element is mounted on a common stem due to the demand for miniaturization as described above. The biggest problem with the downsizing of the device and the combined use of light emitting and receiving devices is a problem of malfunction due to stray light during light reception. FIG. 4 shows a laser element mounting device of a type that does not have the light transmitting window body 13. In this device, the hologram glass 19 is bonded to the cap body 17 with a resin adhesive. As described above, the product of the type that does not have the light transmitting window has a problem due to stray light.

Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a cap for a semiconductor device capable of absorbing reflected light and preventing stray light, and a method for manufacturing the same. is there.

[0005]

The present invention has the following constitution in order to achieve the above object. That is, in the semiconductor device cap, a corrosion-resistant undercoat plating film is formed on the cap body, and a cobalt or cobalt alloy plating film is formed on the corrosion-resistant undercoat plating film in a substantially black color. Further, in a cap for a semiconductor device in which a window for light transmission is hermetically sealed in the cap body, a corrosion-resistant undercoat plating film is formed on the cap body, and cobalt or cobalt alloy plating is performed on the corrosion-resistant undercoat plating film. It is characterized in that the film is formed almost black. In the method for manufacturing a cap for a semiconductor device, electrolytic nickel plating, electroless nickel plating, or other corrosion-resistant undercoat plating is applied to the cap body, and a cobalt or cobalt alloy plating film is formed on the corrosion-resistant undercoat plating film. It is characterized in that the plating film is formed to be almost black by heat treatment. Further, in the method for manufacturing a cap for a semiconductor device in which a light-transmitting window is hermetically sealed in the cap body, the cap body is subjected to corrosion-resistant base plating such as electrolytic nickel plating and electroless nickel plating, It is characterized in that a cobalt or cobalt alloy plating film is formed on the plating film, and the light-transmitting window body is heat-welded on the plating film by using a low melting point glass. Further, the present invention is characterized in that after the plating film is formed into a substantially black color by heat treatment, the light transmitting window body is heat-welded onto the plating film by using a low melting point glass.

[0006]

According to the present invention, a black film is formed on the surface of the cap by the oxidation of the cobalt or cobalt alloy plating film. Therefore, a cap for a semiconductor device capable of absorbing reflected light and preventing stray light from being generated is provided. sell. Further, by forming an oxide film of a cobalt or cobalt alloy plating film on the cap body, it is possible to improve the adhesion between the low melting point glass and the cap body. Further, according to the method of the present invention, a black film can be easily formed on the inner surface of the cap, and the plating step is completed in the step before welding the light transmitting window body, and the low melting point glass undergoes the wet step. Since it does not occur, it is possible to eliminate the situation that the low melting point glass deteriorates due to erosion by the plating solution.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an example of a laser device mounting device cap 20. 21 is a cap body, which is iron-
It is made of metal such as nickel alloy. A through hole 22 is formed in the upper surface of the cap body 21. On the surface of the cap body 21, first, a corrosion-resistant base plating film 23 is formed. Electrolytic nickel plating or electroless nickel plating is suitable as the corrosion-resistant base plating. The thickness of the corrosion-resistant base plating film 23 is not particularly limited, but is preferably about 2 to 7 μm.

A cobalt or cobalt alloy plating film 24 is formed on the corrosion-resistant base plating film 23. For cobalt alloy plating, Ni-Co, Sn-Ni-C
O, Sn-Co, Cr-Co alloy plating and the like are possible. Since the cobalt or cobalt alloy plating film 24 is subsequently subjected to an oxidation treatment to form an oxide film, if the oxide film is too thick, it will be an obstacle in the capping process such as laser welding to the stem in a subsequent process. Do not make it so thick, 0.5-3 μm, preferably 1.5-2 μm
It is about m.

Next, a low-melting glass 25 is used to form a light-transmitting window body 26 made of hard glass into the through hole 22 of the cap body 21.
Cover and weld. As the low melting point glass 25, a tablet formed by molding powder glass into a ring shape is used, and the cap main body 21, the tablet, and the light transmitting window body 26 plated as described above are loaded into a jig (not shown), Heat treatment is performed in an oven at 450 to 500 ° C. for about 30 minutes in an oxidizing atmosphere. As a result, the low melting point glass 25 is melted, and the light transmitting window body 26 can be welded to the cap body 21. At that time, the cobalt or cobalt alloy plating film 2 is formed by the above heat treatment.
4 is oxidized to form a black oxide film. This oxide film is formed at the same time as the tablet is melted, and the adhesiveness with the low melting point glass is improved, and the fixing strength of the light transmitting window body 26 to the cap body 21 also increases.

In addition, the light transmitting window 26 is formed of the low melting point glass 2
The cobalt or cobalt alloy plating film 24 may be blackened by heat treatment before being welded at 5, and then the light transmitting window 26 may be welded by the low melting point glass 25. When the laser element mounting device cap 20 obtained as described above was fixed to the stem on which the laser element was mounted by laser welding and the light emitting and receiving characteristics were examined, particularly when receiving light, the reflected light of the light received was reflected. Was absorbed by the blackened inner surface of the cap body 21, and the generation of stray light could be prevented.

FIG. 2 shows an embodiment of a type which is a cap for a laser device mounting apparatus and which does not have a window 13 for transmitting light. In this embodiment, first, the cap body 12 is subjected to corrosion resistant undercoating such as electrolytic nickel plating, and then the cobalt or cobalt alloy plating film 24 is provided on the corrosion resistant undercoating film 23, and then the cap body 12 is placed in a furnace and exposed to an oxidizing atmosphere. A blackening process is performed by heat treatment. The obtained product had a black film formed on the surface of the cap, as in the above-mentioned Examples, and was able to prevent stray light and could be used as a suitable cap for a laser device mounting apparatus.

Of course, the laser element mounting device cap 20 of the above embodiment can be used not only as a device for both projecting and receiving light, but also as a device for projecting and receiving light. In addition, the inner surface of the cap body 21 is not a mirror surface, but by performing satin finish or the like, it is possible to further improve light absorption.

[0013]

According to the cap for a semiconductor device of the present invention, a black film is formed by the oxidation of the cobalt or cobalt alloy plating film, so that it is possible to prevent the occurrence of stray light as much as possible and prevent malfunctions. it can. In addition, in the product having the window body for transmitting light, the oxide film of the cobalt or cobalt alloy plating film is formed on the cap body, so that the adhesion between the low melting point glass and the cap body can be improved. Further, according to the method of the present invention, it is possible to easily form a black film on the inner surface of the cap, and the plating step is completed in the previous step of welding the window body for light transmission, and the low melting point glass is wet. Since it does not pass through, it has a remarkable effect that it can solve the situation that the low melting point glass is deteriorated due to erosion by the plating solution.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a cap for a laser device mounting apparatus.

FIG. 2 is a cross-sectional view showing an example of a cap for a laser device mounting apparatus.

FIG. 3 is a sectional view of a conventional laser device mounting apparatus.

FIG. 4 is a cross-sectional view of a conventional laser element mounting device.

[Explanation of symbols]

 20 Cap for Laser Device Mounting Device 21 Cap Main Body 22 Through Hole 23 Corrosion Resistant Undercoat Plating Film 24 Cobalt or Cobalt Alloy Plating Film 25 Low Melting Glass 26 Light Transmitting Window

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 31/12 J 7210-4M

Claims (5)

[Claims] 1. A cap for a semiconductor device, wherein a corrosion-resistant underlayer plating film is formed on a cap body, and a cobalt or cobalt alloy plating film is formed on the corrosion-resistant underlayer plating film in a substantially black color. 2. A cap for a semiconductor device in which a window for light transmission is hermetically sealed in a cap body, wherein a corrosion-resistant underlayer plating film is formed on the cap body, and cobalt or cobalt alloy is formed on the corrosion-resistant underlayer plating film. The cap for semiconductor device is characterized in that the plating film of is formed almost black. 3. A method for manufacturing a cap for a semiconductor device, wherein the cap body is subjected to corrosion resistant undercoating such as electrolytic nickel plating or electroless nickel plating, and a plating film of cobalt or cobalt alloy is formed on the corrosion resistant undercoat plating film. Then, the method for producing a cap for a semiconductor device, wherein the plating film is formed into a substantially black color by a heat treatment. 4. A method of manufacturing a cap for a semiconductor device, in which a window for light transmission is hermetically sealed in a cap body, wherein the cap body is subjected to corrosion-resistant base plating such as electrolytic nickel plating or electroless nickel plating, Manufacturing of a cap for a semiconductor device, characterized in that a cobalt or cobalt alloy plating film is formed on the corrosion-resistant undercoating film, and the light-transmitting window body is heat-welded to the plating film by using a low melting point glass. Method. 5. The semiconductor according to claim 4, wherein after the plating film is formed into a substantially black color by heat treatment, the window for light transmission is heat-welded on the plating film by using a low melting point glass. Method for manufacturing device cap.