JPS6144174A - Sputtering device - Google Patents

Abstract

PURPOSE:To improve the defective film thickness distribution owing to the ruggedness of a target surface by improving the cathode side construction of a sputtering device which executes electric discharge between a substrate and cathode in a vacuum and forming a target material as a thin film on the substrate. CONSTITUTION:The target 3 of the batch type magnetron sputtering device is formed to an annular belt shape and is rotationally moved by means of a roller 9. The substrate 5 is carried by a conveyor 6 to the position below the target 3 and when the substrate 5 is brought to a desired position relative to the cathode, the electric discharge is started between the cathode and the substrate 5 by a high-voltage power source 1. The roller 9 is at the same time rotated by a motor and the target 3 rotates as if the belt rotates. Then the relative positional relation between the target 3 and the magnet changes momentarily and since the erosion of the target 3 progresses uniformly without biasing to the specific position, the thin film having the uniform film thickness is obtd.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a sputtering apparatus for forming a thin film of a target material on a substrate by generating a discharge between a substrate and a cathode in a vacuum, and particularly to a sputtering apparatus for forming a thin film of a target material on a substrate. It is about improvement.

[Prior art]

Conventionally, the cathode of a sputtering apparatus is flat or columnar. Therefore, this is particularly noticeable in sputtering equipment such as magnetron sputtering equipment, which applies a magnetic field to a specific part of the cathode, confines electrons in this magnetic field, promotes ionization of the introduced gas, and increases the sputtering speed. Non-uniform erosion of the target occurs.

[Problem that the invention seeks to solve]

Due to this non-uniform erosion, there are disadvantages such as a reduction in the effective utilization of the target material and poor film thickness distribution. In view of the above-mentioned problems, the present invention aims to eliminate these drawbacks.

[Means for solving problems]

The present invention has a target made of a film forming substance in a predetermined vacuum atmosphere and a substrate disposed opposite to this target, and the film material flying from the target is attached to the substrate by a predetermined discharge operation. The sputtering apparatus is characterized in that the target is formed in the shape of an annular belt and is configured to be rotated by a roller.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In Figures 1 to 4, 1 is a DC or AC high-voltage power source for causing discharge, 2 is an impedance matching device, and 3 is a target made flexible by making it into a thin flat belt or caterpillar shape. , becomes the cathode side during discharge. 4 is a vacuum chamber, 5 is a substrate for attaching a film substance, 6 is a conveyor for moving the substrate 5, 7 is a valve, 8 is a vacuum pump, and 9 is a roller for supporting and rotating the target 3. By rotating this roller 9 with a motor or the like, the target 3 can be rotated like a belt. 1
0 is a target cooling device made of non-magnetic material, which is airtight and allows cooling water to flow inside to cool the target surface whose temperature has increased due to discharge. Furthermore, in the magnetron sputtering apparatus, a magnet is also housed inside, and both can be cooled with cooling water.

11 is an earth shield plate for preventing unnecessary discharge. 12 is a tray for moving the substrate, and 13 is a conveyor for moving the tray. 14 is an insulator that electrically insulates the vacuum chamber 4 and the cathode, 15 is a ring for maintaining airtightness, and 16 is a pipe for sending cooling water to the cooling device 10, and the open ends 16a and 16b of the pipe are Cooling water can be supplied from one side and recovered from the other (Figure 3). 17 is a conductor for supplying high voltage to the cathode. 18 is a magnet attached to the magnetron cathode. 19 is a shaft for rotating the roller 9. 20 is a tensioner for applying a constant tension to the target 3.

21 supports the shaft 9 via a bearing (not shown), and also supports the cooling device 10 and the pipe 1.
It is a support body that supports 6. 22 is an insulator that electrically insulates the cathode terra assembly to which a high voltage is applied and the shafts 19a and 19b. 23 is a rotation introducer that introduces rotational motion from the outside while maintaining airtightness in a vacuum, 24 is a gear box, and 25 is a motor. 26
1 schematically shows a part of the magnetic lines of force generated by the magnet 18.

The operation will be explained below in accordance with the above configuration.

Figure 1 shows the state of a batch-type sputtering device before a substrate is inserted and discharge starts; in an in-line-type device, the state is shown after the pretreatment process, which is not shown on the left or right side of the figure, is completed. This is a state in which the substrate 5 has been carried under the target 3 by the conveyor 6 for sputtering. When the substrate is at a desired position relative to the cathode, the high-voltage power supply 1 starts discharging between the cathode and the substrate 5 for film formation. The motor 25 is activated at the same time as the discharge starts. The rotation of the motor 25 is transmitted to the rotation introducer 23 via the gear box 24. The rotational motion introduced into the vacuum by the rotation introducer 23 causes the shaft 19b, the insulator 2
2. Rotate the roller 9 via the shaft 19a. As the roller 9 rotates, the target 3 rotates as if a belt were rotating.

Generally, in a magnetron sputtering device, electrons are confined in a magnetic field (indicated by magnetic lines of force 26) created by a magnet. Therefore, the gas introduced into the sputtering apparatus is actively ionized in this portion. As a result, erosion of the target progresses in this area, and the target undergoes the erosion and deforms unevenly, resulting in uneven film thickness distribution, and the target must be replaced before it is fully used up.

However, if the configuration of this embodiment is adopted, the target 3
As the target 3 rotates, the relative positional relationship between the target 3 and the magnet 18 changes every moment. Target 3 for this
The erosion progresses uniformly without being concentrated in any particular location. As a result, unevenness in film thickness distribution due to irregularities on the target surface is improved. The number of targets 3 decreases in an average manner, and there is no need to replace them while leaving a large amount of unused portions, so there are advantages such as being economical.

[Other Examples]

In the above embodiment, as shown in FIGS. 1 and 2, the traveling direction of the substrate 5 and the rotating surface of the target 3 are parallel to each other, whereas in this embodiment, as shown in FIG. The rotating surface is parallel to the plane of the paper, and the direction in which the substrate moves is perpendicular to the plane of the paper. In such a case,
Even if the substrate 5 is a long object with a fixed cross-sectional shape, the target 3 is flexible. It is possible to match the curvature. By doing this, the distance between the substrate 5 and the target 3 can be made uniform, thereby eliminating unevenness in film thickness distribution caused by unevenness in the distance between the target 3 and the substrate 5, and allowing continuous film formation. Can be done.

〔Effect of the invention〕

As described above, according to the present invention, the target is formed in the shape of an annular belt and is configured to be rotated by a roller, so that the erosion of the target progresses uniformly without being concentrated in a particular location. As a result, the non-uniformity of the film thickness distribution due to the unevenness of the target surface is improved, and the amount of Kugett is reduced evenly.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is an overall configuration diagram, FIG. 2 is an enlarged configuration diagram of main parts, and FIGS. 3 and 4 are side views of a target portion. and a perspective view, and FIG. 5 is an enlarged configuration diagram of main parts showing another embodiment of the present invention. 1...High voltage power supply, 3...Target, 4...Vacuum chamber. 5... Board, 6... Conveyor, 9... Roller.

Claims (1)

[Claims] A sputtering apparatus having a target made of a film-forming substance in a predetermined vacuum atmosphere and a substrate disposed opposite to the target, and in which the film material flying from the target is attached to the substrate by a predetermined discharge operation,
A sputtering apparatus characterized in that the target is formed in the shape of an annular belt and configured to be rotated by a roller.