Study of electrical damage in GaAs induced by SiCl4 reactive ion etching

In the last decade reactive ion etching has become a very important tool for the patterning of submicron features. Although the particle energies involved in this etching process are relatively low, they still are high enough to alter the characteristics of semiconductor materials. In this paper we report on the electrical damage in n- and p-type GaAs induced by SiCl4 reactive ion etching. We found that the etching process causes significant electrical damage extending hundreds of nm deep in the p-GaAs but in n-GaAs only minor changes are observed. The changes in p-GaAs are thought to be due to the formation of EL2 point defects in a concentration comparable to the dopant concentration. Possible explanations for the observed differences in damage between p- and n-type material are given.