Etching of silicon carbide for device fabrication and through via-hole formation

We have investigated the etching of SiC using inductively-coupled-plasma re active ion etching with SF6-based and Cl-2-based gas mixtures. Etch rates h ave been investigated as functions of bias voltage, ICP coil power, and cha mber pressure. It will be shown, for the first time, that SiC surfaces etch ed in Cl-2-based plasmas yield better surface electrical characteristics th an those etched in SF,based plasmas. We have also achieved SiC etch rates i n excess of 1 mum/min which are suitable for micro-machining and via-hole a pplications. Through via-holes obtained in 140 mum thick SiC at an effectiv e etch rate of 824 nm/min have been achieved. To the best of our knowledge, to date, this is the highest effective etch rate for a through via-hole et ched with a masking process compatible with microelectronic fabrication.