芯片制造工艺问答022：热磷酸对Si3N4, Oxide的蚀刻率分别是多少? 蚀刻率可控制因子为何?
Ans 50:1 HF E/R 53+-5A/min of SiOxNy = 120~150A, 220sec
to etch 175A SiOxNyH3PO4 E/R is 60+-6A/min for SIN, 1.5 A/min ~0.25
A/min for oxide, for new H3PO4 acid the [Si] is low and oxide E/R is high bu
