ELECTROCHEMICAL ETCHING OF SEMICONDUCTORS

摘要

PURPOSE: An electrochemical etching method of a semiconductor is provided to uniformly form a nano porous layer on an oxidized emitter layer of a semiconductor wafer. CONSTITUTION: A semiconductor wafer includes an oxidized emitter layer. The semiconductor wafer is contacted with compositions with one or more metal ion supply sources. After an anode current is applied to the composition for preset time, the anode current is not supplied fro the preset time. The above cycle of the anode current is repeated. A nano porous layer is formed on the oxidized emitter layer of the semiconductor wafer. Metal is immersed in the nano porous layer by applying a cathode current and light.