Epitaxially laterally overgrown (ELO)-GaN substrates with dislocation-free
regions can be prepared with a relatively small thickness using atmospheric
pressure metal-organic chemical vapor deposition (MOCVD). In order to dete
rmine the effect of ELO-GaN layer on the reliability of blue-violet laser d
iodes (BV-LDs), we fabricated BV-LDs on the lateral-growth region of the EL
O-GaN layer. The thickness of the ELO-GaN layer was maintained at 5 mum to
inhibit wafer bending, so the total thickness of the BV-LDs was approximate
ly 7 mum. The lifetime of the BV-LDs with a constant output power of 20 mW
under CW operation at 25 degreesC was more than 500h. This lifetime is seve
ral times that of our conventional BV-LDs on sapphire substrates. The ELO-G
aN layer was very effective in raising the lifetime of BV-LDs. (C) 2000 Els
evier Science B.V. All rights reserved.