A MODEL FOR THE ETCH-STOP LOCATION ON REVERSE-BIASED PN JUNCTIONS

This paper reports a model to predict where the silicon anisotropic el ectrochemical etching terminates on reverse-biased pn junctions. The m odel explains why the etching process terminates well before the metal lurgical junction. The effects of the substrate doping, the type of ju nction (step or graded), the etching temperature and voltage bias, as well as the technique used (three and four electrodes) are analysed an d compared with the experimental data. Some limitations and deviations from this theory are also pointed out. (C) 1997 Elsevier Science S.A. All rights reserved.