AlGaAs multiple-wavelength light-emitting bar grown by laser-assisted metalorganic chemical vapor deposition

The first optical device fabricated from epitaxial material grown by laser-assisted crystal growth is reported. The device is an AlGaAs multiple-wavelength light-emitting bar in which the Al composition of the active layer, and thus the emission wavelength, varies as a function of position along the bar. The Al composition is photochemically patterned during growth with an in situ Ar+ laser beam. The energy band gap increases from a minimum of 1.475 eV to a maximum of 1.52 eV over a 4 mm section of the bar. The spatial dependence of the energy band gap is roughly Gaussian and corresponds to the laser intensity profile. The electroluminescent data are presented along with a brief discussion of the laser-assisted crystal growth process.