Electron cyclotron resonance etching of GaAs vias for monolithic microwaveintegrated circuits

We report a high etch rate GaAs via hole etching using Cl-2/Ar plasma in an electron cyclotron resonance system. The effects of process parameters, su ch as RF power, gas flow rate, and microwave power on the GaAs etch rate we re investigated. The influence of RF power, process pressure, and etch time on the resultant profiles were studied. The GaAs etch rate was found to in crease significantly as Cl-2 flow rate, and RF power or microwave power inc reased. A maximum etch rate of 6 mu m/min has been obtained. Studies also s howed that sidewall profile for via patterns can be controlled by varying p rocess pressure and RF power. (C) 2000 Elsevier Science B.V. All rights res erved.