Submicron pattern etching of GaAs by in situ electron beam lithography using a pattern generator

Abstract
Pattern etching of GaAs at submicron size is carried out by in situ electron beam (EB) lithography using a computer‐controlled pattern generator. GaAs oxide on the wafer surface is used as a resist film in EB‐induced Cl2 etching. A 0.5 μm linewidth in a 1 μm pitch line‐and‐space pattern with flat top surface is obtained. Observations of the pattern edge with a scanning electron microscope show that the boundary between the etched area and the oxide mask area is abrupt and that the undulation of the pattern edge is less than about 30 nm.