Electron-cyclotron-resonance plasma etching of the ZnO layers grown by molecular-beam epitaxy

Abstract

Etching of high-quality ZnO layers grown by molecular-beam epitaxy was examined by using electron-cyclotron-resonance plasma etching. Etching rates of ZnO layers were larger using ${\mathrm{CH}}_4$ than ${\mathrm{CF}}_4,$ and four times more enhanced by using a mixture of the two gases. For a ZnO surface covered with photoresist layers by the plasma-etching procedure, degradation was mostly recovered by thermal annealing in an ${\mathrm{O}}_2$ atmosphere at the proper temperatures. This was found to be effective for the recovery of the layers.