Porous-silicon formation in HF-HNO{sub}3-H{sub}2O etchants

摘要

The chemical formation of porous silicon in HF-HNO{sub}3-H{sub}2O etchants is studied experimentally. A technique is devised to determine the ranges in which the proportions of the acids should be varied in order to change from etch polishing to pore formation. The structure and properties of porous layers are examined in relation to the proportion of etchant ingredients.