Characteristics of laser diodes with a partially intermixed GaAs-AlGaAs quantum well

Abstract

Laser diodes (LD's) with a partially intermixed quantum-well (QW) active layer are fabricated by Zn out-diffusion from a p-cladding layer to the QW region. The dependencies of the degree of intermixing, measured by the photoluminescence (PL) shift, on Zn concentration of the p-cladding layer (P/sub clad/) and the Al content of the guiding layer (X/sub g/) in a separate-confinement-heterostructure (SCH) are investigated. P/sub clad/ changes in the range from 1/spl times/10 /sup 18/ cm/sup -3/ to 4/spl times/10/sup 18/ cm/sup -3/ and X/sub g/ changes in the range from 0.21-0.37. When P/sub clad/ is 2/spl times/10/sup 18/ cm/sup -3/ and X/sub g/ is 0.37, large bandgap energy shift of 96.1 meV is observed. The lasing wavelengths of the LD's, with the partially intermixed QW, are blue-shifted linearly with increasing P/sub clad/ and X/sub g/. For the bandgap energy shift of 66.8 meV by PL, the threshold current density is increased by 33% from that of the nonintermixed LD. Reliability of LD's with the partially intermixed QW is investigated for the first time. In spite of a large degree of intermixing the reliability of the LD with the partially intermixed QW of 66.8 meV energy shift by PL is the same as the nonintermixed one, which is confirmed by the aging test of 2500 hours at 45/spl deg/C with the output power of 1 W under CW operation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>