Theoretical study of fabrication of line-and-space patterns with 7 nm quarter-pitch using electron beam lithography with chemically amplified resist processes: II. Stochastic effects

Abstract

Electron beam (EB) lithography is a core technology for nanofabrication. Owing to the increasing demand for high-resolution semiconductor lithography, the requirements for the resist processes of EB lithography for the photomasks used in ArF immersion and extreme ultraviolet lithographies and the mold fabrication of nanoimprints have also become stricter. In this study, the feasibility of single nano patterning by EB lithography with a chemically amplified resist process was investigated from the viewpoint of stochastic effects. The latent images of line-andspace patterns with a 7 nm quarter-pitch (7 nm space width and 21 nm line width) were calculated using a Monte Carlo method on the basis of the sensitization and reaction mechanisms of chemically amplified EB resists. Compared with the line-and-space pattern with a 7 nm half-pitch, line edge roughness (LER) and the stochastic pinching generation are considered to be significantly improved by increasing the pitch. It was found that the suppression of the stochastic generation of bridges is the critical issue in 7 nm quarter-pitch fabrication.

Theoretical study of fabrication of line-and-space patterns with 7 nm quarter-pitch using electron beam lithography with chemically amplified resist process: III. Post exposure baking on quartz substrates

“…In previous studies, 14,15) the possibility of 7 nm space delineation using EB lithography was investigated by extending the line width from 7 to 21 nm to suppress LER and the stochastic defect generation. LER was evaluated by calculating the latent images of line-and-space patterns with a 7 nm quarter-pitch (7 nm space width and 21 nm line width) on the basis of the current performance of chemically amplified EUV resists.…”

Analysis of resist images with pattern defects by Hough transform

“…Other details of the simulation method have been described elsewhere. 22,23) The simulation parameters used are listed in Table I. [24][25][26][27][28] To denoise the results of Mote Carlo simulation, a simple model for the polymer aggregation simulation followed by dissolution judgment was simulated.…”

Effects of photoacid generator decomposition on dissolution kinetics of poly(4-hydroxystyrene) in tetraalkylammonium hydroxide aqueous solutions

“…5) Among the requirements for resist materials, the suppression of stochastic effects, such as line width roughness (LWR) and stochastic defects (pinching and bridging), is the most difficult task to be accomplished. [6][7][8] Currently, chemically amplified resists 9,10) are used as standard materials in high-volume production lines of semiconductors. However, they may not be suitable for further miniaturization owing to acid diffusion.…”