Catastrophic Damage in "Close-Confined" AlGaAs-GaAs Heterojunction Injection Lasers

The peak optical power at which catastrophic damage occurs in heterojunction lasers has been investigated. The allowable peak power is shown to decrease significantly with increased pulse length and representative values are given. No significant temperature dependence of allowable peak power was seen. The use of antireflective films is shown to increase the allowable peak power. For a given pulse length and shape, the power level at which damage occurs in the lowest threshold current density (2000-3000 A/cm2) double heterojunction lasers is 2-3 times lower than for single heterojunction devices. Scanning electron microscopy of the damaged lasers suggests fracture and localized heating and melting at the surface. It is postulated that the local surface heating might be caused by the surface absorption of acoustic phonons generated by stimulated Brillouin scattering.