InGaN Multiple-Quantum-Well Light Emitting Diodes on Si(111) Substrates

An intermediate layer consisting of AlN/AlGaN was used in the growth of InGaN multiple-quantum-well LEDs structure on Si(111) substrates. Crack-free films in 2 inch wafer and high-brightness LEDs were obtained. At 20 mA, the voltage is about 8.0 and 16.0 V for top and backside n-type electrodes, respectively. The EL peaks at ∼506 nm correspond to near band edge luminescence. The full width at half maximum of EL spectrum is 32 nm at 20 mA current. The output power is 23.0 and 19.4 μW at 20 mA for top and backside n-type electrodes, respectively. To our knowledge, this value is the best result of nitride LEDs grown on Si substrate even though it is less than the one on sapphire and SiC substrates.