JPH01179767A - Method for soldering ceramics - Google Patents

Abstract

PURPOSE:To obtain a soldered part having satisfactory airtightness, high strength and superior reliability by metallizing the surface of ceramics, removing part of the resulting surface layer and plating or soldering the metallized surface. CONSTITUTION:At least one kind of IVa metal selected among Ti, Zr and Hf is added to at least one kind of metal (alloy) selected among Cu, Ni and Ag by >=0.5wt.% to obtain an active brazing filler metal. The surface of ceramics is coated with the filler metal by printing and metallized by heating. The resulting surface layer is removed by >=3mum thickness to remove the oxide layer and then the metallized surface is plated or soldered.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of soldering ceramics, and in particular,
The present invention relates to a ceramic soldering method suitable for obtaining high-strength soldering for various ceramics.

[Conventional technology]

Conventionally, Cu has been used as a method for joining ceramics to ceramics or ceramics to metals.

T j, , Z r in Ni or silver solder
A direct bonding method using an active metal solder added with an active metal such as I-I f is disclosed in U.S. Pat. No. 2,739,375.
No. (1956).

It is already known from US Pat. No. 2,857,663 (1958) and the like.

However, the surface of ceramics has not been metalized using active metal solder and joined to other members by soldering. The reason for this is that when soldering is performed directly on a metallized surface using the active metal method or after applying plating such as Ni or Cu plating, low strength is generated from the interface between the metallized surface and the solder or plating. This was due to the problem that some parts of solder with high reliability could not be obtained due to peeling. Until now, the cause of this problem had not been elucidated and no countermeasures had been taken.

[Problem to be solved by the invention]

The above conventional technology uses N] or Cu applied to the metallized surface.
The problem that the plating peels off from the metallized surface with low strength is not considered, and there is a problem that a highly reliable soldered part cannot be obtained.

An object of the present invention is to obtain a highly reliable soldering part by solving the problem.

[Means to solve the problem]

The above object is achieved by plating with Ni or Cu after removing the compound layer formed on the metallized surface by polishing.

[Effect]

In the process of metallizing the ceramic surface using the active metal method, Ti or Z added to copper or silver solder
It was revealed that active metals such as r not only aggregate at the bonding interface with ceramics, but also partially aggregate on the metallized surface, forming an oxide (Tio, Zro) layer approximately 3 μm thick on the metallized surface. did.

The above object is achieved by removing the oxide layer formed on the metallized surface, plating with Ni or Cu, and performing soldering. That is, the metallized surface layer and N
Since there is no oxide layer between i or Cu plating,
The bonding strength between the metallization and the plating interface is improved.

The oxide layer can be removed by mechanical methods such as polishing and honing, or chemical methods such as etching.

Note that the width of the oxide layer varies depending on the amount of Ti or Zr added in the brazing filler metal, but the width of the Ti or Zr layer is
The amount of Zr added is 0.5 wt%. The thickness of the oxide layer in this case is approximately 3 μm, and therefore, this objective can be achieved by removing 3 μm or more of the metallized surface.

〔Example〕

<Example I> On the surface of an AIN ceramic with a thickness of 2 mm and a length of 25 m, a paste-like active metal solder with 3 wt% Ti powder added to silver solder powder was applied by printing to a thickness of 100 μm, and this was applied in a vacuum. Metallization was carried out by heating in an oven at 860°C. A specimen with Ni plating applied to the metallized surface as it is, and a specimen with Ni plating applied to the metallized surface after polishing.
A strength test was conducted on each of the plated specimens. When the metallized surface is not polished, the bonding strength is less than 3 kgf/no'', whereas when it is polished, a high bonding strength of 10 kgf/mn+2 or more is obtained.If the metallized surface is removed by polishing, the metallized surface A high bond is obtained between the layer and the Ni plating, which results in
Reliable ceramic soldering becomes possible.

<Example ■> On the surface of AIN ceramics with a thickness of 2 mm and 25 horizontal and vertical strokes, a paste-like active metal solder containing 3 wt% Ti powder added to copper powder was printed and coated to a thickness of 100 mm. is heated in a vacuum at 1000°C for metallization,
A strength test similar to Example I was conducted. In this case as well, it was clear that the specimens with polished metallized surfaces had higher strength.

〔Effect of the invention〕

According to the present invention, the bonding strength between the metallized layer and the Ni plating can be increased, and ceramic soldering with good airtightness and high strength can be obtained.

Claims (1)

[Claims] 1. In a method for soldering ceramics, the surface of the ceramic is metalized by an active metal solder in which at least one of group IVa metals such as Ti, Zr, and Hf is added to any one of Cu, Ni, and Ag alone or in an alloy. After that, a surface layer of 3 μm or more of the metallized metallization is removed, and the surface of the metallized metallization is plated or soldered.