JPH093637A - Split sputtering target - Google Patents

Abstract

PURPOSE: To provide a slit sputtering target in which no bonding material enters the space of joints by welding recessed parts formed at notched parts formed on joints on a rear of the targets to join a plurality of targets. CONSTITUTION: A notched part 7 or a chamfer-finished part is formed on a joint part of a rear 9 of a target 1. The target 1 and the other targets 2... which are similarly worked are continuously arranged, and the recessed part formed by the corresponding notched parts 7 is welded 8. The joined split targets 1... are joined with a backing plate 5 through a bonding material 6 on the rear 9. No bonding material 6 enters the space between the joints even when the temperature rises in sputtering the split targets 1..., and deterioration, warpage, etc., of the target can be prevented from being generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering target used for forming a thin film. More specifically, it relates to a divided metal (including alloy) sputtering target.

[0002]

2. Description of the Related Art Generally, a target used in a sputtering method is used by bonding a backing plate with a bonding material.

In recent years, the sputtering apparatus used for the sputtering method has become larger and larger in order to improve the mass productivity of thin films and increase the area of thin films. In this case, it is often impossible to manufacture a single target due to the problem of warpage that occurs when manufacturing a large target and processing techniques such as cutting and polishing. For this reason, it is the current situation that a so-called split sputtering target is produced, in which a plurality of targets are manufactured, and the targets are joined and bonded to a backing plate with a bonding material.

There are also cases where different types of metal targets are bonded to the same backing plate and their alloy thin films are formed by the sputtering method. Also in this case, a split sputtering target is required.

[0005]

In the case of the split sputtering target described above, a gap is likely to be formed at the joint between the target and another target adjacent thereto. In general, an indium alloy, a solder, a brazing material, or the like is used as the bonding material, but these bonding materials are fluids when they are joined to the backing plate, so they easily penetrate into the gaps.
In addition, heat may be generated when the target is sputtered, and the bonding material may be melted by the generated heat, and the bonding material may enter the gap between the targets.

When the target is sputtered in such a state, the bonding material is also sputtered, and the bonding material is mixed as an impurity in the formed thin film, which causes the film characteristics to be significantly deteriorated.

In order to eliminate such a defect, it is conceivable to weld the entire seam of each target as shown in FIG. In the figure, 8 is a welded portion. However, in this case, due to the welding heat, the metal structure such as the coarsening of the crystal grains of the joint portion of each target is deteriorated, or the target warpage occurs, which is a disadvantage in the manufacturing technology of the sputtering target. is there. For example, when the target warps, it becomes impossible to bond the target to the backing plate with the bonding material, and when the crystal grains in the bonded portion become coarse, the uniformity of the sputter rate is impaired.

The present inventor has, in order to eliminate such drawbacks,
Previously, a patent application was filed for an invention that a backing material such as a polymer heat-resistant sheet or a metal sheet of the same quality as the target is attached to the joint of each target to prevent the bonding material from entering the gap between the targets (Japanese Patent Application No. -75963).

An object of the present invention, like the above-mentioned invention, is to provide a split sputtering target in which the bonding material does not enter the gap between the joints of the target.

[0010]

DISCLOSURE OF THE INVENTION According to the present invention, in a joint between targets of a divided metal (including alloy) sputtering target, a notch or a chamfered finish is provided at a joint on the back surface of the target, The recesses formed in the notched portion or the chamfered finished portion of the target are joined by welding.

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view of a rectangular plate-shaped target, in which a notch portion 7 is provided on the back surface 9 of the target. FIG. 2 is a perspective view of a split sputtering target 20 in which four targets are installed on a backing plate. Reference numeral 5 is a backing plate, 6 is a bonding material, 1 to 4 are targets, and the recesses formed by the notches of the opposing targets are welded in a state in which the targets are close to each other so that there is no gap between them. . 8 is a welded part.
In this case, if a welding projection is formed, it is cut off and finished into a flat surface, and the target back surface 9 is bonded to the backing plate side by the bonding material 6.

Next, another embodiment will be described with reference to the drawings. However, if the specifications are the same as those of the previous embodiment, the description is omitted. FIG. 3 is a perspective view of a square plate-shaped target having a chamfered finish 7 '. FIG. 4 is a perspective view of a split sputtering target 30 in which four targets of FIG. 3 are installed. In this case, the concavities formed by the chamfered finishes of the opposing targets are welded. As is clear from the figure, the cross section of the recess of the previous embodiment is square, but the cross section of the recess of this embodiment is triangular.

It is obvious that the above-mentioned structure prevents the bonding material from entering the gap between the joints of the target.
Further, as shown in FIG. 5, since the joint is not entirely welded but the target rear surface is partially welded, the metal structure of the sputter surface is not deteriorated and the target is not warped.

The sectional structure of the welded part is not limited to the above-mentioned embodiment, and any structure may be used without departing from the gist of the present invention. Further, in the above embodiment, an example of four targets was shown as a split sputtering target, but the number of targets is not limited and the number is not limited. Further, the present invention can be applied not only to a rectangular plate-shaped split sputtering target but also to a disk-shaped or other-shaped split sputtering target.

The welding member used in the present invention may be any welding member, but it is preferable to use a welding member of the same metal (including alloy) as the target if possible.

Recently, a so-called integral structure type sputtering target in which a sputtering target and a backing plate are made of the same material has been widely used. This sputtering target also tends to be large in size, and is often difficult to manufacture for the above reasons. However, since the back surface of this sputtering target is in direct contact with cooling water, it cannot be divided.

However, according to the present invention, at the seam between the targets, the recesses formed by the notched portions or the chamfered finish portions of the opposing targets are joined by welding, so that water leakage does not occur, and therefore the splitting is performed. This makes it possible to manufacture a large-scale integral structure type sputtering target, and its industrial value is extremely large.

[0018]

According to the present invention, the split sputtering target is characterized in that the bonding material does not enter the gap between the joints of the target, and therefore impurities are not mixed into the formed film. In addition, when there are a relatively large number of division targets, Japanese Patent Application No. 1-75
In No. 963, since the seam of each target is only lined with a lining material and the adhesive strength is poor, if the amount of heat generated during sputtering is unevenly distributed among the split sputtering targets, some of the overheated targets will be packed. Easy to peel off from the plate. However, according to the present invention, since each target is completely welded on the back surface of the target, there is an advantage that such partial peeling of the target does not occur.

[Brief description of drawings]

FIG. 1 is a perspective view of a target provided with a cutout portion according to the present invention.

FIG. 2 is a split sputtering target 2 according to the present invention.
It is a perspective view of 0 .

FIG. 3 is a perspective view of a target provided with a chamfered finish according to the present invention.

FIG. 4 is a split sputtering target 3 according to the present invention.
It is a perspective view of 0 .

FIG. 5 is a perspective view of a split sputtering target in which the entire seam of each target is welded.

[Explanation of symbols]

 1, 1 ', 1 "to 4, 4', 4" Target 5, 5'Backing plate 6, 6 'Bonding material 7 Notch 7' Chamfer finish 8 Weld 9, 9 'Target backside

Claims (1)

[Claims] 1. A seam between the targets of the divided metal sputtering target is provided with a notch portion or a chamfered finish portion at a joint portion on the back surface of the target, and the notch portion or the chamfered finish portion of the facing target is formed. A split sputtering target characterized in that the recesses are joined by welding.