Patent ID: 8716144

Claim:
A method for manufacturing a semiconductor device comprising: a positioning step of positioning a silicon substrate inside an etching chamber, the silicon substrate having a photoresist film including an opening part formed thereon; a first etching step of performing plasma etching on the silicon substrate positioned inside the etching chamber by using a mixed gas including at least SF 6 , SiF 4 and O 2 with the photoresist film as a mask; and a second etching step of forming a hole in the silicon substrate by performing the plasma etching on the silicon substrate by using a mixed gas including at least SF 6 , SiF 4 , O 2 , and HBr after the first etching step, wherein a preliminary etching step of etching the substrate until reaching a depth that is substantially equal to an opening width of the opening part is performed beforehand, prior to the first etching step, said preliminary etching step using a mixed gas including at least SF 6 , SiF 4 , O 2 , and HBr, wherein during said first etching step, a thin film including silicon dioxide is deposited on a surface of the photoresist film, and wherein flow rates of the SF 6 , SiF 4 , and O 2 , are not changed in said preliminary etching step, said first etching step, and said second etching step.