SMM Enters 6-inch Sapphire Substrate Commercial Production

Sumitomo Metal Mining (SMM) announced on Monday the firm starts commercial production of 6-inch diameter sapphire substrate, establishing an integrated production line from crystal growth to substrate manufacturing at Okuchi Electronics, the wholly owned subsidiary in Kagoshima, Japan. Sapphire substrate consumption is expected to increase mainly for light emitting diodes (LEDs) applied to luminaires. The commercial line construction will complete in October 2012. Capital expenditure will total 1.2 billion yen involving already implemented investment.

SMM has provided samples of 6-inch sapphire substrates those which were manufactured at SMM’s Ome District Division in Tokyo. SMM has procured sapphire crystal from third parties and then sliced and polished wafers at Ome. SMM plans to remain two productive sites, Ome and Okuchi Electronics, for a while. In future production and R&D of sapphire substrate will be integrated in Ome site.

Gallium nitride based on sapphire substrate is used for white and blue LEDs. Adoption of white LEDs is especially increasing for backlights of large-size liquid crystal panel TVs and indoor luminaires. Majorly used sapphire substrates are 2-4 inch diameter at present while LED makers strongly request cost cut. Then larger diameter substrates are expected to be used, from which more LED chips can be cut out.