Bridgelux has demonstrated highest Lm/W levels for Gallium Nitride on Silicon (GaN-on-Si) and has broken its own record with this achievement.
The company has extended its lead in manufacturability and performance of GaN LEDs. It demonstrated high performance levels of LEDs which were comparable to that of sapphire-based LEDs. Warm white LEDs made from GaN on Si chips provided 125 Lm/W at 80 CRI and 2940K color temperature. Cool white LEDs provided 160 Lm/W at 4350K CCT.
The cost of production of conventional LEDs has curtailed its adoption in commercial buildings and residences. These LEDs are made from silicon carbide and sapphire substrates which are comparatively more costly than silicon. Growing GaN on low-cost and larger-sized silicon wafers can improve the cost factor by 75%.
Bridgelux has showcased the growth of layers of GaN on 8" silicon wafers using its buffer layer technology. GaN has a larger thermal expansion coefficient than silicon. This can lead to cracks in the epitaxial films or cause bowing in the wafers. Bridgelux’s technology enabled production of wafers that were crack-free and did not break at room temperature.
Encapsulated 1.5 mm blue LEDs emitted 591 mW at 350 mA exhibiting 59% wall plug efficiency. The LEDs can be used at high current densities due to their low forward voltages of 2.85 V at 350 mA. The LEDs emitted 1.52 W blue power at 3.21 V forward voltage and a 1 A drive current. Bridgelux demonstrated sigma 6.8 nm wavelength uniformity for 8-inch LED wafers.
Bridgelux’s buffer layer technology process can decrease the manufacturing cost of LEDs and allow them to compete against white lighting technology.