PRESSURE AND IRRADIATION ANGLE DEPENDENCE OF MASKLESS ION-BEAM ASSISTED ETCHING OF GAAS AND SI

Maskless ion beam assisted etching of GaAs and Si has been investigated. Focused Ga** plus ion beam was used to irradiate GaAs and Si in chlorine and xenon difluoride gas atmosphere, respectively. It was found that an optimum gas pressure existed to improve the etching rate. The etching rate showed a maximum at a bombarding angle of 60 degree -70 degree . The simulation of the etching profile was in reasonable agreement with the observed profiles. It was also found that redeposition effect is absent for ion beam assisted etching.