Micron Features In III-V Materials By Photoelectrochemical Etching Of Focused Ion Beam Induced Damage Patterns

A method of patterning n-type GaAs, InP, InGaAs and InGaAsP by photoelectrochemical (PEC) etching in conjunction with a submicron focused gallium ion beam (FIB) at low dose is de-scribed. The ion beam is used to produce damage in a desired pattern on the material. Subsequent PEC etching of the material reveals the ion induc5d featurs in relief. The procedure is highly sensitive, requiring a dose of only 5x109 ions/cm2 (about 1 ion every 1500Å) for the differential etch to become apparent. The sensitivity allows rapid pattern generation in our FIB system.