Hi, I am in the process of fabrication of some patterning on SiN membrane window. It involves of lithography, film deposition and liftoff. Since membrane is so fragile(the thickness is about less or around 100nm), it is very easy to break during lift off/ cleaning process which may require sonication, some times even N2 blow dry may damage membrane window. I am wondering if anyone have experience of how to handle it and share it with me. Thanks Xiaoyong