| 摘要 |
PURPOSE:To enable etching having high selectivity to SiO2 as a foundation and vertical sectional form by using CF3X and (X2) or (X')2 (X and X' are halogen elements except fluorine) as the reactive ion etching gases of a polycrystal silicon film, bringing total pressure to predetermined pressure or lower and plasma-discharging the gas. CONSTITUTION:A ground electrode 5 forming parallel plate electrodes together with a cathode 2 constitutes an anode together with a reaction chamber 1. A carbon board 6 is placed onto the surface of the cathode 2, and a sample to be processed 7 is fitted onto the board. A gas such as CF3Br+Cl2 gas is introduced from a gas introducing port 8 shaped to the reaction chamber 1, and high-frequency power is applied to the cathode 2 while discharging gas from an exhaust port 9, thus plasma-discharging the gas. Reactive ion etching having the high ratio of selection is attained when the total pressure of the gas is 0.12 Torr or lower. |
