Deformation-free overgrowth of reactive ion beam etched submicron structures in InP by liquid phase epitaxy

Submicron grating patterns written by electron beam lithography are transferred into InP substrates by reactive ion beam etching (RIBE) using an Ar/O2 gas mixture. Trapezoidal grating structures with a depth of 0.15 μm are generated. The influence of the preheating cycle prior to liquid phase epitaxy (LPE) on the grating shape is investigated as a function of different cover materials. We obtain deformation-free LPE overgrowth of the dry etched corrugations applying the GaAs cover technique. In contrast to wet chemically etched gratings identical grating profiles are formed in different crystallographic directions by RIBE and successfully overgrown by LPE.