Fabrication of SixNy Nanomechanical Structures Using Traditional Lithography and Gas Isotropic Etching

We presented a novel idea for the fabrication of nanomechanical structures using a combination of traditional lithography technology and gas isotropic etching. The process starts from a 4" p-type silicon wafer, then two S_ixN_y and SiO₂ layers are alternatively deposited. After the patterning using traditional lithography with 2-mum resolution, S_ixN_y pattern is obtained which is then used as the hard mask for gas isotropic etching, and a narrowed nanoscale SiO₂ pattern is realized. The obtained structures can be further used to form nanochannel or nanoresonant devices. The SEM images show a nano-channel with triangle section and a suspended nanoscale S_ixN_y mechanical structure. The minimum structure size is in the range of 100 nm.