Abstract
A novel tensile strain barrier reducing (TSBR) structure is grown between window and cladding layers of multi-quantum-well (MQW)-AlGaInP light-emitting diodes (LEDs). The TSBR film (100∼200 Å of Ga 0.65 In 0.35 P) is of lattice size and valence band energy intermediate between those of window and cladding layers, thus reducing band offset and decreasing device forward bias from 2.55 V to 1.92 V at 20 mA, with concomitant improvements in dynamic resistance and junction heating. The TSBR layer increases power efficiency by 30% at 20 mA and up to 65% at high current conditions. The reduced junction heating of the with-TSBR design may be of significant advantage to device quality, reliability and lifetime, especially for high current applications.