JPH04301074A - Target for sputtering - Google Patents

Abstract

PURPOSE:To offer a target for sputtering which enables extension of time for continuous sputtering and improves the effect of production control by suppressing peeling of particles adhered to the target or to a backing plate. CONSTITUTION:Whole or a part of the sputtering surface except for bonding surface, or the target surface except for the bonding surface and the whole or a part of the backing plate exposed to the sputtering atmosphere are made rough.

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 thin films.

0002

BACKGROUND OF THE INVENTION Sputtering is widely used as a technique for depositing various solid substances onto a substrate in the form of a thin film. However, among the target material particles ejected by such sputtering phenomenon,
Only some of the particles adhere to the substrate and form a thin film; other particles adhere to the inner walls of the device or redeposit to the surface of the target and its backing plate. Therefore, as sputtering is performed continuously, the amount of deposits on the inner walls of the apparatus, the target, and the backing plate surfaces increases, and when the amount of deposits exceeds a certain level, it becomes easy to peel off. In particular, in the case of an industrial in-line sputtering apparatus, when opening and closing the chamber partition walls, the above-mentioned deposits may peel off and fly up due to the pressure difference between the chambers and adhere to the substrate. Since such deposits cause defects such as pinholes in the thin film and increase the defective rate of products, it is desirable to avoid their occurrence as much as possible.

In practice, in order to prevent such deposits from peeling off, it is necessary to clean the inside of the device and the target surface to remove the deposits every time sputtering is performed continuously. Become. Cleaning the inside of the device and the target surface requires breaking the vacuum, which is a very inefficient process, including the time required for evacuation to resume operation. Therefore, in order to improve productivity, it is desired to extend the time during which sputtering can be performed continuously and reduce the number of times of cleaning.

The present invention extends the continuous sputtering time by suppressing the peeling of particles attached to the target or the target and its backing plate.
An object of the present invention is to provide a sputtering target that can significantly improve productivity.

[0005]

[Means for Solving the Problems] The present invention roughens all or a portion of the target surface excluding the bonding surface, or the surface of the target surface excluding the bonding surface and its backing plate exposed to the sputtering atmosphere. By making it a surface, the above-mentioned problem has been achieved.

The bonding surface in the present invention refers to the bonding surface between the target and the backing plate. Therefore, the target surface other than the bonding surface includes the target side surface or, in magnetron sputtering, the target center which is hardly subject to erosion due to the influence of the magnet shape. This includes departments, etc. Furthermore, the sputtering atmosphere refers to an atmosphere in which plasma is generated, a sputtering phenomenon occurs, and film formation is performed. Also, what is a rough surface?
This means creating a surface texture that can capture particles that are ejected and scattered from the target. Specifically, the roughening described above can be achieved by blasting with glass beads or the like or iron particles. The present invention will be explained below according to examples.

[0007]

[Example 1] Ta target (200mmφ, thickness 6m
The central part (50 mmφ) of the sample m) was blasted with #80 glass beads to make the central part surface rough. When a magnetron sputtering (side sputtering type) test was conducted using this target, it was possible to continuously form films on 30 batches of substrates without cleaning the apparatus. For comparison, a similar sputtering test was conducted using a similar target that was not subjected to the blasting process, and cleaning was required every three batches of sputtering. As a result, it was found that the number of possible batches for targets treated according to the present invention was increased approximately 10 times compared to targets that were not treated. When the center of the target was examined after the sputtering test, a large amount of powder was found to have adhered to the surface of the target, which had been roughened by the blasting process. This is because the roughened surface effectively traps coarse particles,
This indicates that scattering onto the substrate is prevented.

[0008]

[Example 2] Instead of the glass beads of Example 1, #30
When the same process as in Example 1 was carried out except that the blasting was performed using Fe shot of I understand.

[0009]

[Example 3] Similar to Example 2, the center part of the target was made of Fe.
Sputtering was carried out in the same manner as in Example 1 using a target and backing plate that had been roughened by shot blasting, and the side surface of the target with a thickness of 6 mm and the side surface of the backing plate with a thickness of 8 mm were subjected to the same blasting process. It was possible to continuously form a film on 40 batches of substrates without using any adhesive. When the sputtered target was observed, a large amount of deposits was observed in the blasted areas, indicating that the roughened target surface effectively trapped coarse particles.

0010

Effects of the Invention According to the present invention as described above, the time during which continuous sputtering can be performed can be extended by the extremely simple means of roughening a part of the target surface or the surfaces of the target and backing plate. This reduces the number of cleaning operations and significantly improves productivity.

Claims (1)

[Claims] [Claim 1] All or part of the target surface excluding the bonding surface, or the target surface excluding the bonding surface and its backing plate, which is exposed to the sputtering atmosphere, is characterized by having a rough surface. Target for sputtering.