Internal stress and degradation in short-wavelength AlGaAs double-heterojunction devices

Aging tests of incoherently operated zinc-doped double-heterojunction (DH) lasers designed for short-wavelength (0.71-0.72 micron) operation show that the introduction of buffer layers between the substrate and the DH structure leads to a drastic reduction in gradual degradation. This is attributed to a decrease in lattice mismatch stress.