Multi-wavelength lasers fabricated by an Al layer controlled quantum well intermixing technology

Abstract

We report that the shift in the band gap of Al0.3Ga0.7AS/GaAs quantum well structures can be precisely controlled by an Al layer buried between a spin-on silica film and a wet-oxidized GaAs surface. The blueshift in wavelength of the Al0.3Ga0.7As/GaAs quantum well photoluminescence (PL) depends linearly on the thickness of the buried Al layer. By changing the Al layer thickness, the PL peak wavelength can be tuned from 7870 Å for the as-grown sample to 7300 and 7050 Å after 20 and 45 s rapid thermal annealing at 850°C, respectively. Applying this technology, Al layers with different thickness, i.e., no Al, 200 and 300 Å thick, were applied to the oxidized GaAs surface in three adjacent regions with 200 μm spacing on a quantum well laser structure sample. Three wavelength lasers were successfully fabricated in a single chip by a one step rapid thermal annealing. All the lasers have similar threshold current and slope efficiency. © 2000 American Institute of Physics.