基板バイアスにより制御されたＺｎＯ薄膜の結晶性とドライエッチングにより形成される側壁形状との相関

Abstract

The microstructure and dry etching properties of ZnO films deposited by rf magnetron sputtering have been investigated. It was found that preferred orientation of ZnO films could be controlled from (002) to (101) and (100) mixed phase applying the substrate bias power. Dry etching of the ZnO films was conducted by a helical coil reactor. The etching rate of the films was strongly depended on the power applying the helical coil. Optical emission microscopy measurement showed that the etching rate of the ZnO film was rapidly increased when the emission intensity ratio of excited atomic hydrogen (Hα) to CH increased in the plasma. Excited atomic hydrogen served as etching gas to react with the carbon layer on ZnO film surface. The etching shape of ZnO sidewall was affected by the crystal structures of the films. The rough sidewall morphology of dry-etched (002)-oriented ZnO films was due to the columnar grains, comparing to the smooth sidewall obtained from the film with (101) and (100) mixed structure.