Maskless selective growth and doping of GaAs using a low energy focused ion beam for in-situ micro-device structures fabrication, and its evaluation

摘要

We attempted to achieve maskless selective epitaxial doped-GaAs films by using a Sn-Ga or Be-Ga low energy focused ion beam. XTEM images and resistivity of the films showed the FIB needed to be used below about beam energy of 30-60 eV for good crystalline quality and electrical characteristics. The Hall mobility of Sn-doped GaAs films was 2170 cm{sup}2V{sup}(-1)s{sup}(-1) at a carrier concentration of 2.7×10{sup}17 cm{sup}(-3), and that of Be-doped GaAs films was 35.6 cm{sup}2V{sup}(-1)s{sup}(-1) at a carrier concentration of 1.32×10{sup}18 cm{sup}(-3). However further improvement of resistivity and ion beam resolution is considered to be an actual problem for micro-device structure fabrication.