JPH06108248A - Sputtering source - Google Patents

Abstract

PURPOSE:To prevent the breakdown of insulation caused in such a manner that a deposit deposited on a projecting part formed on an annular anode is peeled and its small pieces stick to a backing plate or the like by covering the side faces of a planar target. CONSTITUTION:The distance of a gap 23 provided between a planar target 3 and an annular anode 6 is made sufficiently smaller than the mean free pass of ions formed by a sputtering stage, and it is not allowed to reach a backing plate 4 or the like as well as the annular anode 6 is not provided with a projecting part. Furthermore, the surface of the planar target 3 is placed on the plane same as the surface of the annular anode or above the annular anode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a sputtering source used in a sputtering apparatus, particularly a planar type magnetron sputtering apparatus.

[0002]

2. Description of the Related Art When thick film sputtering is performed by the planar magnetron sputtering apparatus shown in FIG. 1, a deposition layer composed of components constituting the target 3 is formed on the inner wall of the film forming chamber 1 other than the substrate 2, in particular. When it becomes thicker, it often peels off partially, and the small piece 19 may drop on the target 3 located below.

For this reason, among the small pieces 19 which have fallen off, those which have been adsorbed and attached to the outer edge E (see FIG. 1) on the target 3 come into contact with the annular anode 6 located adjacently and inclined outward. In some cases, this caused dielectric breakdown and stopped the discharge.

Further, the relationship between the target 3, the backing plate 4 and the annular anode 6 will be described with reference to FIG. That is, the annular anode 6 is arranged on the outside of the backing plate 4 which is longer than the target 3, but 2
A gap e of about mm is provided, and the protrusion 20 of the annular anode 6 that covers the gap e is formed. This protrusion 20
Thus, a structure is adopted in which argon ions due to the sputtering process are prevented from etching the backing plate 4 through the gap e. Therefore, the protruding portion 20 is located above the surface of the target 3 and covers the outer edge E of the target 3.

[0005]

Backing plate 4
The formation of the protruding portion 20 of the annular anode 6 which is installed to prevent the etching of FIG.
This causes the small piece 19 to fall.

The present invention has been made under the above circumstances, and an object thereof is to provide a novel sputtering source.

[0007]

A coolable backing plate, a plate-shaped target arranged in contact with the backing plate, an annular anode arranged apart from the periphery of the plate-shaped target, and the plate-shaped target surface. The sputtering source according to the present invention is characterized by an annular anode surface that is equal to or lower than the plate-shaped target and intersects in the thickness direction of the plate-shaped target, and a void located between the annular anode end and the plate-shaped target end.

[0008]

As described above, the side surfaces of the annular anode and the plate-shaped target are provided with the gaps so that the backing plate can be seen from the outside, and the surface of the plate-shaped target is flush with or higher than the surface of the annular anode. Moreover, since the sputtering is performed under a pressure of about 0.1 to 10 Pa, it has been found that if the void is sufficiently small with respect to the mean free path (mean free path), the ions do not reach the backing plate and are not etched. .
The present invention has been completed based on such knowledge.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described with reference to FIGS. FIG. 2 is a cross-sectional view showing an outline of a planar-type sputtering apparatus equipped with the sputtering source of the present invention, and FIG. 3 is a cross-sectional view showing an example of a target having a thickness larger than that of the anode. Take over the one used in the technical column.

As shown in FIG. 2, a magnetic field device 5, a plate-shaped target 3 and a substrate 2 necessary for sputtering are installed.
The film forming chamber 1 is composed of a plate-shaped target 3, a substrate 2 made of polycarbonate, which is opposed to the plate-shaped target 3, and an anode surrounding the plate-shaped target 3.

The magnetic field device 5 effective for sputtering the plate-like target 3 is arranged eccentrically from the center of the film forming chamber 1 and hence the center of the plate-like target 3. The surface portion of the plate-shaped target 3 which is parallel to the magnetic lines of force (not shown) generated from the outer magnet 5 _b and the inner magnet 5 _a forming the magnetic field device 5 is most sputtered. Therefore, it surrounds the inner magnet 5 _a constituting a permanent magnet arranged outside the magnet 5 _b circular. The central axis A of the film forming chamber 1 is connected to, for example, a motor (not shown) and eccentrically rotated from the center of the plate-shaped target 3. Further, the backing plate 4 is attached to the plate-like target 3 to which a discharge power of about 25 W / cm ² or less is applied, and the cavity 8 is provided inside to provide the water supply pipe 2
Connect to 1. Thereby, the cooling water is circulated to maintain the surface temperature of the plate-shaped target 3 at about 100 ° C.

As a result, it is possible to prevent the plate-shaped target 3 from being deformed and prevent a gap from being formed between the plate-shaped target 3 and the backing plate 4.

The Alcon gas required for the sputtering process is supplied from the introduction section 7, and then sputtering power is supplied to bombard the target surface with argon ions to sputter the target material, for example, Al, to deposit Al on the substrate 2. . The exhaust port 22 is used to exhaust gas and the like generated by such a sputtering process.

The sputtering process in the planar type magnetron sputtering apparatus having such a structure has a
It is carried out under a pressure of about Pa to 10 Pa, but the annular anode 6
The surface of the plate-shaped target 3 and the surface of the plate-shaped target 3 may be located on the same plane or above the surface of the annular anode 6, and the latter is shown in FIG.

The plate-shaped target 3 and the annular anode 6 are also provided.
A space 23 of about 1 mm is formed between them, as shown in FIG. This distance is 0.
This is a sufficiently small value for the mean free path of ions generated under a pressure of about 1 Pa to 10 Pa.

Therefore, the backing plate 4 is not etched by the ions, and the material of the backing plate 4 is not mixed into the coating formed on the substrate 2.

[0017]

The sputtering source according to the present invention has a space 23 between the plate-shaped target 3 and the annular anode 6,
The distance is kept small enough for the mean free path of the ions produced by the sputtering process. As a result, the backing plate 4 is not etched, and peeling of small pieces deposited on the protrusion 20 formed on the annular anode 6 as in the conventional case is eliminated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main part of a conventional sputtering apparatus, showing a state in which a deposit is peeled off and attached.

FIG. 2 is a sectional view showing a main part of a sputtering apparatus to which a sputtering source according to the present invention is applied.

FIG. 3 is a cross-sectional view of an example of a sputtering source applicable to a sputtering apparatus, in which the surface of the plate-shaped target 3 is located above the surface of the annular anode 6.

[Explanation of symbols]

 1: film forming chamber, 2: substrate, 3: plate-like target, 4: backing plate, 5: magnetic field device, 6: annular anode, 23: void.

Claims (1)

[Claims] 1. A coolable backing plate, a plate-shaped target arranged in contact with the backing plate, an annular anode arranged away from the periphery of the plate-shaped target, and a surface equal to or lower than the surface of the plate-shaped target. A sputtering source, comprising: an annular anode surface that intersects the thickness direction of the plate target located therein; and a void located between the annular anode end and the plate target end.