Inductively coupled plasma etch damage in 4H-SiC investigated by Schottky diode characterization

Ti Schottky diodes have been used to investigate the damage caused by induc tively coupled plasma (ICP) etching of silicon carbide. The Schottky diodes were characterized using TV and CV measurements. An oxidation approach was tested in order to anneal the damage, and the diode characterization was u sed to determine the success of the annealing. The barrier height, leakage current, and ideality factor changed significantly on the sample exposed to the etch. When the etched samples were oxidized the electrical properties were recovered and were similar to the unetched reference sample (with oxid ation temperatures ranging from 900 degreesC up to 1250 degreesC). Annealin g in nitrogen at 1050 degreesC did not improve the electrical characteristi cs. A low energy etch showed little influence on the electrical characteris tics, but since the etch rate was very low the etched depth may not be suff icient in order to reach a steady state condition for the surface damage.