Dear All, Generally speaking, SiN mask is patterned by dry etching.But I want to do some wet etching with SiN mask. At first I sputtered a SiN film on a Si wafer.Then a standard photolightprocess was processed. Now I don`t know how to etch SiN with the photoresist.Is the hot phosphoric acid OK?But I`m afraid that the photoresist can not last for long in the hot phosphoric acid. So what can I do? Please help me. Thanks! LeiNie in HUST of China P.R. 2005-01-13