| 摘要 |
A method for shrinking equivalent critical dimension of mask by in situ polymer deposition and etching is proposed. The invention comprises following key points: First, when a photo-resist is formed on a substrate by a mask and a photolithography process, a polymer layer is formed on said photo-resist. Second, a plasma reactor with at least two independent power sources is used to form and etch the polymer layer, where ion density and ion energy of plasma are adjusted respectively by different power sources. Third, voltages of all power sources are adjusted such that etching rate and depositing rate are equivalent on surface of the photo-resist and etching rate is obviously larger than depositing rate in bottom of any structure of the photo-resist. Therefore, the sidewall of any structure is filled by a conformal polymer layer and then width of any structure is efficiently decreased. By the way, the critical dimension of any structure is significant smaller than critical dimension of the mask. In other words, equivalent critical dimension of mask is shrunk by the invention. Obviously, the photo-resist with shrunk critical dimension can be used to form semiconductor device with critical dimension that is more narrow than critical dimension of the mask.
|
