Improvements in or relating to semiconductor devices.

摘要

A manufacturing method of a semiconductor device, such as a dynamic RAM having fin-shaped, stacked cell capacitor in memory cell characterized by the following facts: first insulating layer (MTO layers (20), (28)) and second insulating layer (BPSG layers (21), (29)) are formed in order on a silicon semiconductor substrate (1); of them, at least the second insulating layer is subject to an etching processing step to manufacture the semiconductor device; the etching solution used in this manufacturing process contains 1.6-6 wt% of hydrogen fluoride and 2.5-10 wt% of ammonium fluoride. Effect: The etching rate ratio of the first insulating layer and second insulating layer can be set appropriately, and the various layers can be etched with excellent controllability. In this way, the surface is flat after the etching processing, and a uniform etching operation can be performed.