ION-BEAM SMOOTHING OF INDIUM-CONTAINING III-V COMPOUND SEMICONDUCTORS

Reactive ion beam etching (RIBE) with N-2 has been used for smoothing of rough InAs, InP, and InSb surfaces, prepared by argon ion beam etch ing (IBE). The evolution of the surface roughness and morphology has b een studied by atomic force microscopy (AFM) as a function of the N-2 RIBE process parameters lion beam energy, ion beam angle of incidence, and ion dose). A drastic improvement of the surface roughness has bee n observed for ion beam angles near normal incidence and larger than 7 0 degrees with increasing ion doses. By using this technique, the init ial root-mean-square (rms) roughness of, e.g., InSb of about 40 nm cou ld be decreased to about 1 nm.