JPS61288066A - Target and its production - Google Patents

Abstract

PURPOSE:To obtain a target wherein the water cooling effect is sufficient and the generation of a crack is less and the sputtering velocity is large by utilizing amorphous C and bonding a thin strip made of metal to a target material used in the thin film formation due to the sputtering. CONSTITUTION:After coating C of an amorphous state on one side of a target material used in the thin film formation, a metallic or alloy thin strip is mounted thereon and press-contacted at high temp. to remove C and the thin strip is bonded on the target material to obtain a target. The used thin strip may be nearly the same shape as one side of the target material and may be divided into several pieces and combined with each other. C of the amorphous state has such a role that the joint of ceramic or an intermetallic compd. and metal or alloy is reinforced. In this method, the cooling effect of the target is made large and the bonding strength is large and therefore it is stable even in the high-velocity sputtering. As the thin strip, the following material is selected which is excellent in the wetting characteristics for a material having low m.p. such as In and solder and can be easily joined to oxygen free Cu used in a supporting plate at low temp.

Description

Detailed Description of the Invention - (Industrial Application Field) The present invention relates to a target used when forming a thin film on a substrate surface by sputtering or the like.

Material is ejected from the surface of the target in atomic form by ions, and is deposited on the substrate by a bias voltage.

(Prior Art) In sputtering, a target is constantly exposed to intense ion bombardment and becomes extremely hot.

During normal low-speed sputtering, the temperature rise was not so severe, and since tough metal materials were often used as target materials, it was a good idea to fix the target to the support plate with bolts or screws. However, recently, with the application of magnetron sputtering, target cooling has become an important issue due to local ion bombardment of the target and an increase in sputtering speed.
A strong bond between the support plate and the target has become an unavoidable problem.

Furthermore, the target materials used are brittle materials such as ceramics and intermetallic compounds, which tend to break when used without cooling, which has increased the importance of bonding. Conventional bonding has been performed using indium, solder, silver solder, or the like.

It has also been practiced to provide these materials with a backing coating of about 0.2 to 15 .mu.m.

(Problem to be solved by the invention) Among the conventional bonding methods, indium.

Methods using solder or silver solder cannot be used with target materials that have poor wettability with these metals in a molten state. In particular, most ceramics and intermetallic compounds have poor wettability. Furthermore, even when these are lined, the bonding strength between the backing material and the target material is low when using ceramics or intermetallic compounds, and when high-speed sputtering is performed, peeling or cracking occurs from the bonded portion.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a target with a sufficient water cooling effect, less occurrence of cracks, and a high sputtering speed, and a method for manufacturing the same.

(Means for solving the problem) Amorphous C is adhered to one side of the target material used for thin film formation, and pressure welding is performed at high temperature with a metal or alloy ribbon through the amorphous carbon. is removed, bonded, and then glued to the support plate. The ribbon to be used may have approximately the same shape as one side of the target material, or may be divided into several parts and combined.

(Function) Amorphous C has the role of strengthening the bond between ceramics or intermetallic compounds and metals or alloys. By joining the target material and the metal or alloy thin ribbon using this method, the cooling effect of the target is large, and the joint strength is also high, so it is stable even during high-speed sputtering.

For the metal or alloy ribbon, select one that has good wettability with low melting point materials such as indium and solder, and can be easily joined at low temperatures to oxygen-free copper used for the support plate.

These characteristics are: firstly, when the target and the support plate are joined, the distance between the target and the support plate, the target material and the Cu
- Greatly reduces the stress generated between the C plates. Similarly,
It increases the cooling effect during sputtering and withstands the stress generated in the target material with high bonding strength. If the thermal expansion coefficients of the target material and the metal or alloy ribbon are significantly different, it is also effective to divide the ribbon to absorb expansion and contraction.

(Example 1) The sputtering apparatus is as shown in FIG.

Inside the vacuum chamber 1 are a cathode 2 and an anode 3. A target 4, which is a thin film material, is attached to the cathode 2 on a support plate 5, and a substrate 6 on which Mll is to be formed is placed on the anode 3. The electrodes are structured so that a DC high voltage 7 of 1 to 2 KV can be applied between the anode 3 and the cathode 2 from the outside. The vacuum chamber 1 is equipped with a high vacuum exhaust hole 8 and a gas introduction pulp 9.

When starting sputtering, first evacuate the inside of the tank to a sufficiently high vacuum. This is to prevent residual gas in the tank from becoming an impurity material in the film produced during sputtering. Next, while the vacuum chamber 1 is connected to the exhaust system, Ar gas is introduced from the gas introduction pulp 9, and the pressure inside the vacuum chamber is controlled to a level that allows sputtering. In this state, a high DC voltage is applied between the cathode 2 and the anode 3. In this way, cathode 2 and anode 3
An electric field will be applied to the gas that exists between the two.

Target material 1100II 1φ x 6 used in sputtering equipment that uses a target of 100 + 1111φ
The plate was bonded to a support plate made of oxygen-free copper under the conditions shown in Table 1. C in an amorphous state was coated on the target material to a thickness of about 5 μm by sputtering. 900℃ in a vacuum of about 3X10-3Torr using a hot press machine.
When pressurized with a pressure of 200 ko/cn+' at a temperature of ℃, the carbon is blown away and the bond is formed. Table 1 shows the working conditions and bonding strengths of the conventional method using only backing and the method of the present invention.

A, 0. - H*t k et al. 11. Old jealousy 880.
Example 2 A MOSi2 target material of 220φ was joined to a Cu-C plate having a thickness of 111111 mm in the same manner as in Example 1. At this time, 42Ni-Fe having a width of 100III was used, and the circumferential portion of the target material was cut along the circumference so that the total diameter was 220φ.

As in Example 1, this target was also adhered to a support plate via indium. This target could be used without cracking even when 10KW of power was applied.

(Effects of the Invention) As described above, the present invention provides a sufficient cooling effect on the target material, the strength of the joint, and the use of indium.

Good bonding with solder and the like reduces the stress between the target material and the support plate, increasing the sputtering speed and stabilizing the nine conditions, resulting in a significant improvement in the production efficiency.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of an example of a sputtering apparatus.

Claims (2)

[Claims] (1) A target characterized in that a target material is coated with C in an amorphous state, and then a metal or alloy ribbon is placed on the target material and pressed at high temperature to remove C, and the ribbon is adhered to the target material. (2) After coating the target material with amorphous C, a thin metal or alloy ribbon is placed on the target material, the C is removed by pressure bonding at high temperature, and the ribbon is bonded to the target material to manufacture the target. Characteristic target manufacturing method.