Ion beam induced dry etching and possibility of highly charged ion beam

Dry etching techniques employing ion beam induced surface reaction and the possibility of highly charged ion beam in dry etching are described, and the preliminary work on dry etching of GaAs using highly charged ion (HCI) is also presented. In usual dry etching, total etch rate is a summation of the physical sputtering rate, the chemical etching rate, and the ion-induced chemical etching rate. When Ar/Cl2/GaAs system is used, the ion-induced chemical etching yield which is the key issue in dry etching to obtain the good controllability is enhanced by the charge state of HCI as well as the physical sputtering yield. Application of HCI to materials processing is also discussed briefly.