| 摘要 |
PURPOSE:To contrive improvement in etching speed by a method wherein an AlxGa1-xN(0<=X<=1) semiconductor is etched with the plasma of carbon tetrachloride (CCl4) gas. CONSTITUTION:A sample 30 is formed by laminating an AlN buffer layer 2, a GaN layer 3, and a mask 4 consisting of sapphire on a sapphire substrate 1. When plasma etching is conducted, samples 30 and 32 are placed on an electrode 24, and after a reaction chamber 20 has been brought into the state of vacuum degree of 5X10<-6>Torr by evacuating the residual gas in the reaction chamber 20, CCl4 gas is introduced by controlling its flow speed to 10cc/min. Then, when high frequency power is supplied between the electrode 24 and 22, glow discharge is started between the electrodes, the introduced CCl4 gas is turned into a plastic state, and the etching on the samples 30 and 32 is started. After the etching is conducted for the prescribed period, the part which is covered by the mask 4 on the sample 30 is not etched, and only the exposed GaN layer 3 is etched. As a result, etching speed can be improved. |
