What is a metal target?

What is a metal target?

Target material is one of the main materials for preparing thin films. It is mainly used in integrated circuits, flat panel displays, solar cells, recording media, smart glass, etc., and has high requirements for material purity and stability.

Working principle of sputtering target material: Sputtering is one of the main technologies for preparing thin film materials. It uses ions generated by an ion source to accelerate and gather in a vacuum to form a high-speed energy ion beam to bombard the solid surface. The ions and the atoms on the solid surface exchange kinetic energy, causing the atoms on the solid surface to leave the solid and deposit on the substrate surface. The bombarded solid is the sputtering target material.

The development trend of target materials is: high sputtering rate, grain orientation control, large size, and high-purity metal.

The target material is welded by "target blank" and "back plate".

(1) The target blank is the target material bombarded by the high-speed ion beam. It is the core part of the sputtering target material and involves high-purity metal and grain orientation control. During the sputtering coating process, after the target blank is hit by ions, its surface atoms are sputtered and scattered and deposited on the substrate to form an electronic thin film.

(2) The back plate plays a major role in fixing the sputtering target, which involves welding processes. Since high-purity metals have low strength, the sputtering target needs to be installed in a dedicated machine to complete the sputtering process. The machine is in a high-voltage, high-vacuum environment. Therefore, the sputtering target blank of ultra-high-purity metal needs to be joined to the back plate through different welding processes. The back plate needs to have good electrical and thermal conductivity.