Studies of chemically amplified deep UV resists for electron beam lithography applications

Chemically amplified resists have been widely used in deep UV optical lithography. In this paper, we characterized positive deep UV resists for high-resolution electron beam lithography applications. Results indicate this deep UV resist is very high sensitive and suitable for high throughput e-beam lithography applications. In general, deep UV resists are not suitable for sub-100 nm resolution lithography, except for strictly process control. After a simple thermal flow procedure, the trench-width can be easily down to 70 nm. It is also convenient to get a sub-70 nm contact hole pattern by utilizing commercial deep UV resists with this strategy. Many factors influence performance of resists such as soft bake, post exposure bake, exposure dose, and thermal flow, which are discussed and optimized. Suitable dry etching properties of deep UV resists are also characterized for pattern transfer.