SAN FRANCISCO—Japan's Toshiba Corp. announced it would start mass production of white light-emitting diodes (LEDs) on a production line that the company will build within its 200-mm wafer fab at subsidiary Kaga Toshiba Electronics Corp. in northern Japan.
Toshiba (Tokyo) said it expects mass production of the LEDs to commence in October.
According to Toshiba, thanks to their energy efficiency, white LEDs are winning wide acceptance in general purpose lighting, TV backlighting and other applications. The company estimates that the market for white LEDs will grow from about 700 billion yen (roughly $8.75 billion) to 1 trillion yen (about $12.5 billion) in fiscal 2013.
Toshiba said it would use gallium nitride-on-silicon—a technology that secures growth of gallium nitride (GaN) crystals on a silicon substrate—to the development of white LEDs. The company said it has collaborated with Bridgelux Inc., a developer a of LED lighting technologies, in white LED chip development since January.
The combination of Bridgelux's crystal growth and LED chip structure and Toshiba's advanced silicon process and manufacturing technology has succeeded in developing a prototype chip with a maximum optical output of 614mW, Toshiba said. Toshiba will build on this achievement to start mass production of white LEDs, the company said.
Toshiba said it considers white LEDs a next-generation growth area in the discrete business. By advancing the establishment of white LEDs production in addition to power devices, a current strategic focus product area, Toshiba said it intends to enhance the discrete business.
Kris, it has been mostly GaN on Sapphire so far because the epitaxy buffer layer AlN and the active layer InGaN have so far been processed mostly on Sapphire. That is not the only substrate of choice, there is bulk GaN, SiC (early Cree versions), Si and composites.
If yield issues are proven, it makes sense to move away from Sapphire. Ideally, the LED industry has to work toward vertical designs with backside contact which can result in smaller chips. It is not clear if moving to Si substrate achieves that.
It is ironic, Toshiba on one end announced cut in its NAND Flash production by 30%.