LONDON – Toshiba has announced that this month it will start production of white light emitting diodes intended for use by makers of general purpose and industrial lighting using Bridgelux technology.
The white LEDs are made using gallium nitride grown on 200-mm diameter wafers of silicon. Toshiba said it plans to ramp capacity up to 10 million LEDs per month and said it wants to secure a 10 percent market share by 2016.
Production of LED chips is typically done on 2- to 4-inch sapphire wafers. Bridgelux Inc. (Livermore, Calif.) developed a method of manufacturing gallium nitride LEDs on 200-mm silicon wafers, which provides a cost advantage. With backing for Bridgelux from Toshiba, that process was brought to Kaga Toshiba Electronics Corporation, a discrete products manufacturing facility in northern Japan. Plessey Semiconductors Ltd. (Plymouth, England) has also adopted a GaN-on-Si process for LED production but is presently ramping with 6-inch diameter wafers.
The first product of the Toshiba GaN-on-Si line is the TL1F1 series of LEDs that produce 112 lumens at 350-milliamps current. The packaged parts measure 6.4-mm by 5.0-m by 1.35-mm.
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