Improved characteristics of 660nm AlGaInP red laser diodes by precise control of the V/III ratio in metal-organic vapor phase epitaxy

The effects of the group V/III ratio during low-pressure metal-organic vapor phase epitaxy on laser performance have been investigated for GaInP∕AlGaInP laser diodes. The quality of GaInP is found to be better at a V/III ratio much lower than an optimal V/III ratio for AlGaInP. GaInP∕AlGaInP laser diodes with the emission wavelength of 660nm were grown at a low V/III ratio for GaInP quantum wells and at a high V/III ratio for AlGaInP waveguide and clad layers. As a result, device characteristics, particularly operating lifetime, are much improved as compared with those of devices grown with a constant high V/III ratio.