Patent ID: 7704861

Claim:
An electron beam micro/nano fabrication method for allowing negative-tone lithography for irradiating, onto a surface of a GaAs thin layer formed on an Al x Ga y In 1-x-y As z P 1-z (0≦x, y, z≦1) surface including GaAs alone or an LnP substrate, an electron beam controlled to an arbitrary electron beam diameter and current density so as to selectively substitute or generate Ga 2 O 3 for a natural oxide layer formed on the GaAs surface, then dry-etching the GaAs layer surface by a bromide in single atomic layer units, and thereby selectively removing the natural oxide layer other than the part substituted by the Ga 2 O 3 , GaAs, and Al x Ga y In 1-x-y As z P 1-z wherein an acceleration voltage of the electron beam is 50 keV or less and the amount of dose thereof is 10 16 to 10 20 electron/cm 2 , and microstructures having different aspect ratios can be formed by an identical step by controlling the amount of dose of an electron beam by controlling the amount to be etched at the time of dry etching by controlling the amount of irradiation of the electron beam and thereby generating Ga 2 O 3 different in crystallinity on the GaAs layer surface.