DRY-ETCHING OF GERMANIUM IN MAGNETRON ENHANCED SF6 PLASMAS

Magnetron enhanced reactive ion etching of germanium was investigated in SF6 plasmas. Ge etch rates were determined as a function of cathode power density (0.1-0.5 W/cm(2)), pressure (2-8 mTorr), and SF6 flow r ate (2-11.5 seem). Etch rate increased as pressure and flow rate were increased, but exhibited the unusual characteristic of decreasing as c athode power was increased, Auger electron spectroscopy measurements s howed the presence of a sulfur residue (<1 at. %) upon etching, while scanning electron microscopy revealed that smooth etched surfaces were attained in SF6 magnetron enhanced plasmas. (C) 1997 American Vacuum Society.