JPH07331426A - Method for joining sputtering target material - Google Patents

Abstract

PURPOSE:To firmly braze a target to a cooling member at the time of brazing the difficult-to-braze Cr-base target to the cooling member consisting of a Cu- base metal, etc., by vapor-depositing an alloy of specified composition on the joining surfaces of the cooling member and target. CONSTITUTION:A sputtering target material 1 of Co-Cr-Ta, etc., is brazed to a cooling member 4 of Cu, Cu alloy or stainless steel with a brazing filler metal 3. In this case, the vapor-deposited film of Cr/Ni/Au/Sn alloy is previously formed on the joining surfaces of the target 1 and cooling member 4 to modify the surfaces, and the wettability with the brazing filler metal is improved. An In solder foil is then placed between the vapor-deposited films of the cooling member 4 and the target material 1 as the brazing filler metal 3, and the target 1 is brazed to the member 4. The target 1 is brazed to the member 4 in this way with a high adhesive strength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for brazing a target material of Cr-based difficult-to-bond material to a stainless steel cooling member which is copper or a copper alloy or a difficult-to-bond material.

[0002]

2. Description of the Related Art Conventionally, a cooling member is generally made of copper having a good thermal conductivity, and copper has a property of being very easily wet by any brazing material. Further, since the surface of copper can be easily modified by plating, it is necessary to consider the joining only when the target material is a difficult joining material.

Further, since the copper and the target materials have different thermal expansion coefficients, the targets in the cooling process of the brazing are as described in JP-A 1-262088, 1-268989 and 2-11759. The brazing is performed while heating the material and the cooling member so that the contraction amounts are the same, and providing a warp caused by a difference in thermal expansion and a warp in the opposite direction according to the warp amount.

However, it is practically difficult to control the temperature and to give a proper warp in the opposite direction.

In Japanese Patent Application No. 5-310038, Ti / Pt / Au / Sn is used as a vapor deposition material.
t / Au / Sn is very expensive, and joining is very expensive.

[0006]

The sputtering target material is usually bonded to a cooling member made of copper and a copper alloy, mounted on a sputtering apparatus, and water-cooled before use.

However, in some sputtering target materials, from the viewpoint of preventing the formation of rust due to water cooling, a difficult-to-bond material such as stainless steel may be used as a cooling member rather than copper as the component system.

[0008] Stainless steel is generally hard to be wet with most brazing filler metals and is difficult to join.

Co-based targets, Nb-based targets, and NiO targets are also unlikely to wet the brazing material.

Therefore, if no special flux is used,
The brazing material does not spread wet.

However, if a flux is used to bond the sputtering target material used in a high vacuum state, harmful gas is generated, which hinders sputtering.

Further, there is a method of vapor-depositing Ti / Pt / Au and Cr / Ni / Au on the target and the cooling member for surface modification. It is necessary to perform sputtering in. In the conventional method, the wettability and adhesion between Au and In solder was sufficient,
Under high vacuum, wetting and adhesion had to be further improved.

An object of the present invention is to provide an inexpensive method which can be used even when the difficult-to-join target and the difficult-to-join cooling member are used under high vacuum.

[0014]

[Means for Solving the Problems] Cr / Ni / Au / Su are vapor-deposited on a Co-based or Nb-based target, a NiO target, and a stainless steel cooling member, which are difficult-to-bond materials, to modify the surface.

According to this method, since no special flux is used, no harmful gas is generated even in a high vacuum state.

Sn in the uppermost film undergoes a eutectic reaction with Au to become Au-Su. Alternatively, since the In solder also contains Sn, it is very wettable, and Au and I are intercalated through Sn.
n Solder has improved wettability compared to the conventional one, and bonding with strong adhesion can be performed.

[0017]

[Function] The SUS material and the target material which are difficult to wet the brazing material 3 are vapor-deposited with Cr / Ni / Au / Su, which are very easily wetted.
Bonding with strong adhesion is possible.

By forming a film and modifying the surface, it is possible to easily perform brazing with higher adhesion strength than in the past.

[0019]

[Example] Cr / Ni / Au / on SUS304 20-square TP material
The thickness of the Sn vapor deposition film 2 is set to 0.1 μ / 0.2 μ / 0.2 μ.
Vapor deposition was performed at a value of 0.1 μm and a tape peeling test was performed.

As a result, no peeling was observed at all.

Similarly, Co-Cr-Ta target material 1
A Cr / Ni / Au / Sn vapor deposition film 2 was vapor-deposited on and a tape peeling test was conducted, but no peeling was observed.

In addition, conventional Cr / Ni / Au, Ti / Pt
/ Au and the SUS material were evaluated for adhesion strength by a die shear test.
A doubled value was obtained.

As a result of the preliminary test, it was confirmed that there was no problem in the vapor deposition property on the SUS cooling member 4 and the Co-Cr-Ta target material 1, and it was also confirmed that the strength was higher than before.

Next, φ130 / φ70 × 12t SUS
Cooling member 4 (SUS304) and φ240 × 6tCo-Cr-T
a The target material 1 was joined.

Since the SUS cooling member 4 has a ring shape,
Create a vapor deposition mask so that only that part is vapor-deposited, and
r / Ni / Au / Sn are 0.1 / 0.2 / 0.2 respectively
A vapor deposition film was formed with a film thickness of /0.1 μm.

Next, a mask is formed on the target material so as to be vapor-deposited on the bonding surface of the SUS ring, and Cr / Ni is used.
The vapor deposition film was formed so that the vapor deposition film 2 of / Au / Sn has the same thickness as the SUS material.

In is deposited on the bonding surface of the target after vapor deposition.
A solder foil is placed and heated to 180 to 200 ° C., and In solder welded on the joint surface is thinly spread on the entire surface of the target.

Similarly, In solder is thinly spread on the entire surface of the SUS cooling member 4 as well.

Next, an In solder foil was laminated between the target and the joining surface of the SUS cooling member 4 without slippage, and a clip of about 10 kg of weight was put on the foil and the ambient temperature was set to 20.
Place in a 0-230 ° C oven and hold for about 30 minutes.

As a result of joining in this way, joining without peeling or deformation was achieved.

As a result of the radiation inspection of the bonded product, the area ratio of the bonded portion was 95% or more, which was good. It was possible to easily join the SUS cooling member 4 and the Co-Cr-Ta target material 1 which have been difficult to join up to now, at low cost without using a special jig or tool.

[0032]

According to the present invention, Cr / Ni / Au / S
By performing n vapor deposition on the target and the cooling member, it can withstand use under high vacuum.

[Brief description of drawings]

FIG. 1 is an explanatory view showing stacking of respective members before joining.

[Explanation of symbols]

1 ... Co-Cr-Ta target material, 2 ... Cr / Ni /
Au / Sn vapor deposition film, 3 ... brazing material, 4 ... SUS cooling member.

Claims (1)

[Claims] 1. A method of joining a sputtering target material, comprising a target material and a cooling member made of copper and a copper alloy or stainless steel, which is heated and air-cooled with In-based solder to bond the target material and the cooling member. To Cr
/ Ni / Au / Sn is vapor-deposited and joined, The joining method of the sputtering target material characterized by the above-mentioned.