Growth characteristics of GaAs-Ga1−<i>x</i>Al<i>x</i>As structures fabricated by liquid-phase epitaxy over preferentially etched channels

Abstract

In this paper, we report our studies of the liquid-phase epitaxy of GaAs and Ga1−xAlxAs single- and double-layered structures over preferentially etched channels in GaAs substrates. Results obtained indicate that various optical waveguide structures providing lateral optical confinement can be fabricated by this etch-and-fill technique. Further, it is found that the filling of the channels is dictated by surface tension of the melt rather than by preferential growth. This growth characteristic lessens the dependence of the final profile of the grown layer on the initial etched profile and makes the etch-and-fill technique particularly suitable for the fabrication of optical bends.