Developing supply systems by 2025, promoting the recycling of limited precious metal resources, and contributing further to the circular economy

January 31, 2024

TANAKA Kikinzoku Kogyo K.K., which develops industrial precious metals products as one of the core companies of TANAKA Precious Metals, announced that it has established a jig cleaning method called TANAKA Green Shield. This cleaning method is characterized by nickel plating on the adhesion-preventing plate¹, a component of vacuum film formation equipment² used in semiconductor manufacturing and other processes. When using a nickel-plated adhesion-preventing plate, PGM³ sputtered films, including platinum and palladium, can be easily detached from the plate.

TANAKA is developing a recycling business for this use case. After detaching sputtered films adhering to components, mainly made from stainless steel, of vacuum film formation equipment such as sputtering and vacuum deposition equipment, the recovered precious metals are refined and returned to the customer with the precision-cleaned components.

This cleaning method takes advantage of a unique TANAKA technology related to base plating. Applying a nickel plating to an adhesion-preventing plate enables PGM sputtered films to be detached through chemical treatment without damaging the base material. This method makes it easier than previous methods to detach PGM sputtered films, so it is expected to reduce the amount of cleaning agent required when cleaning equipment, in turn contributing to reduced environmental impact. With an anticipated reduction in recovery loss of precious metals scattered around during the grinding process, this method is also expected to achieve higher PGM recovery rates with lower costs.

TANAKA aims to develop the TANAKA Green Shield system to support a wide variety of component shapes and sizes and to expand PGM film recovery rates by six times the current level by 2025.

¹ Adhesion-preventing plate: Plate installed to prevent film adhering to the interior wall of a film formation chamber (sealed reaction vessel used for producing physical or chemical reactions)
² Vacuum film formation equipment: Equipment used in thin film formation processes, including sputtering and deposition, employed in the manufacture of semiconductors
³ PGM: Platinum group metals comprising six precious metals (platinum, palladium, rhodium, ruthenium, iridium, and osmium)

20240131_TANAKA Establishes New Method of Recovering Precious Metals Adhering to Vacuum Film Formation Equipment Components.pdf