A method is disclosed for micromachining the surface of a silicon substrate which encompasses a minimal number of processing steps. The method involves a preferential etching process in which a chlorine plasma etch is capable of laterally etching an N+ buried layer beneath the surface of the bulk substrate....http://www.google.fr/patents/US5531121?utm_source=gb-gplus-shareBrevet US5531121 - Micromachined integrated pressure sensor with oxide polysilicon cavity sealing
Micromachined integrated pressure sensor with oxide polysilicon cavity sealing
