Toshiba Electronics Europe (TEE) has announced the first devices in its second generation of LETERASTM white light-emitting diodes (LEDs) fabricated using a gallium nitride-on-silicon (GaN-on-Si) process. The 1W TL1F2 LEDs offer a cost-competitive alternative to current LED packages, allowing manufacturers of general purpose and industrial LED lighting to drive down costs.
High-performance white LEDs have typically been fabricated on expensive sapphire substrates in relatively small 100mm or 150mm wafer sizes. In contrast, Toshiba has developed a process that enables GaN LEDs to be produced using more cost-effective 200mm silicon wafers. This helps to reduce costs by replacing expensive sapphire substrates with more cost-competitive silicon substrates while making use of existing silicon fabrication facilities.
Luminous efficacy of the TL1F2 white LEDs has been improved compared with the TL1F1 series by optimising the package and increasing the optical output power of the GaN-on-Si LED chips. The TL1F2 series offers a full correlated colour temperature (CCT) range from 2700K to 6500K, with minimum colour rendering index (CRI) values of 80 and 70 respectively. Typical luminous flux of the 1W LEDs ranges from 104 lumen to 135 lumen depending on colour temperature and CRI.
The new devices are supplied in a standard 6450 package measuring just 6.4mm by 5.0mm by 1.35mm. Typical driving current (IF) is 350mA, with a typical forward voltage (VF) of just 2.85V helping designers to reduce system power consumption. An operating temperature range of -40°C to 100°C makes the TL1F2 series suitable for both indoor and outdoor use in applications such as lamps, ceiling lighting, street lights and floodlights.