Facet oxidation of InGaAs/GaAs strained quantum-well lasers

Abstract

Aging tests were carried out on as-cleaved InGaAs/GaAs strained quantum-well ridge waveguide lasers. Although the lasers have immunity to sudden failure and have degradation rate as low as 2×10−5 h−1, after over 6000 h of operation, they readily suffered facet oxidation. The measured oxidation rate was comparable to that of GaAs quantum-well lasers and one order of magnitude higher than that of lattice-matched InGaAs/InP lasers. This high oxidation rate is considered to be caused by light absorption in the vicinity of the facet where the band gap is reduced because of the stress variation from biaxial to uniaxial.