InGaN/GaN MQW SCH lasers grown on SiC

Laser diode structures were fabricated by metal-organic chemical vapor deposition (MOCVD) from the AlN-InN-GaN system on single crystal 6H-SiC substrates. An AlGaN conducting buffer layer was developed for these devices, which provides a vertical conduction path between SiC substrate and the active device region. Violet and blue multiple quantum well (MQW) separate confinement heterojunction (SCH) LDs were fabricated having InGaN wells and GaN barriers. The lowest pulsed operation room temperature threshold current density obtained for lasing was 7.1 kA/cm2 in a 4-well structure. Lasing has also been obtained in these same devices at duty cycles up to 75%.