Double heterostructure laser diode emitting at 1·06 μm using quaternary alloy of InGaAlAs

Abstract

A double heterostructure laser emitting at a wavelength of 1·06 μm is reported, using the quaternary material of InGaAlAs as the active layer and InAlAs as the cladding. The layers are grown by the molecular beam epitaxy technique. The threshold current is 25mA at a current density of 1·4 kA/cm-2, for an active layer thickness of 0·05 μm and contact stripe width of 6 μm. The laser structure grown is well characterized with SIMS and chemical staining, to reveal the layers, and double crystal X-ray diffraction for the crystalline quality. A single-mode laser peak is observed up to twice the threshold current, where the FWHM is 30 Å. At higher currents, emission at lower wavelengths of about 1 μm has been observed. This is attributed to the alloy clustering/segregation effects in the quaternary layer. © 1995 Taylor & Francis Ltd.