Fabrication of sub 20-nm wide grooves in a quartz mold by space narrowing dry etching

Abstract

This paper describes a simple fabrication process of fine groove structures for quartz molds used in UV nanoimprint lithography. Grooves that are finer than the ''spaces'' in line/space resist patterns can be obtained on a quartz substrate with the aid of thin Cr layer and a dry etching process using CHF3. The main cause of the groove width narrowing is deposition of fluorocarbon polymer. By changing etching conditions, a large amount of space narrowing is realized. Grooves with widths of 18nm and 62nm were successfully obtained from 85-nm and 200-nm wide space resist patterns, respectively.