MANUFACTURE OF SEMICONDUCTOR INTEGRATED

摘要

PURPOSE:To facilitate forming a trench in a semoconductor substrate with normal taper and facilitate filling the trench satisfactorily with conductive films or insulating films in the trench by a method wherein the deposition speed of wall deposition films deposited on the side walls of the trench and the etching speed are controlled. CONSTITUTION:Wall deposition films 17 are formed on the side walls of a trench 16 and the trench 16 is formed in such a manner that the ratio between the deposition speed of the wall deposition films 17 and the etching speed of a semiconductor substrate 3 is controlled and a self-bias potential is controlled. With this constitution, as the deeper part of the trench 16 has the smaller diameter, the trench 16 can be formed to have normal taper. Moreover, as the opening of the top end of the trench 16 is not attacked by ions of etching because the etching is progressed while the wall deposition films 17 are being deposited on the side walls of the trench 16, the trench 16 can be formed without dimensional variation between the trench 16 and an etching mask 14.