In situdissolution analysis of half-pitch line and space patterns at various resist platforms using high speed atomic force microscopy

Preliminary results of in situ analyses of dissolution of resist patterns of half-pitch (hp) lines and spaces (L/S) using high-speed atomic force microscopy are discussed. Initial experiments were conducted on an EUV-exposed 32 nm hp L/S pattern using a standard concentration (0.26 N) of tetramethylammonium hydroxide (TMAH) developer solution. This was done using a carbon nanofiber-based cantilever tip and after various tool enhancements and optimizations. Difference in the dissolution characteristics of various resist polymers such as polyhydroxystyrene (PHS)-based and hybrid (PHS-methacryl) resists was observed. These results are in agreement with the previously obtained results of measurements performed with 32 nm isolated line patterns on resist films developed with diluted developer solutions (1/20 of 0.26 N TMAH), where the PHS-based resist showed a uniformly dissolved, grain-like dissolution characteristic, while the hybrid resist exhibited resist swelling of the exposed resist film.