Semiconductor injection laser with low leakage current - has substrate with three semiconductor layers which are selectively etched away to substrate and shape restored by fourth layer

摘要

N type CaA1As, and GaAs and GaA1As layers are successively grown on a semi-insulating GaAs substrate doped with Cr to form a semiconductor chip. Predetermined portions of those layers are selectively etched away to a depth reaching the substrate. Then a P type GaA1As layer is epitaxially grown on the etched portion to restore the original shape of the chip. The chip is heated to form a pn junction in at least the GaAs layer serving as a light emitting religion. The laser has a reduced rate of change of leakage current with tep.