Abstract: We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography (EBL).The proximity effect is extended to develop a flexible and practical method for preparing metal (e.g.Au or Ag) nanogaps and arrays in combination with a transfer process (e.g.,deposition/lift-off).Different from the direct gap-writing process,the nanogap precursor structures (nanoconnections) were designed by GDSII software and then written by electron beam.Following a deposition and lift-off process,the metal nanogaps were obtained and the nanogap size can be lowered to ~10nm by controlling the exposure dose in EBL.

Key words: metal nanogap, nanofabrication, proximity effect, electron beam lithography