Jeong-Sik Kim

Measurement of EUV resists performances RLS by DUV light source

Recently published experimental results indicate that current resists seem to be very hard to meet the International Roadmap for Semiconductors (ITRS) goals for Resolution, Line Width Roughness (LWR) and Sensitivity (RLS) simultaneously. This RLS trade-off has also been demonstrated through modeling work. RLS goals may not be possible for lithographers to achieve all three simultaneously by applying current standard chemically amplified resists and processes. In this paper, we have synthesized the various PAG(photo-acid generator) bound polymers for different anion size and other molecular weight (Mw). In order to reach the EUV resist targets, we investigate the effect of diffusion length on energy latitude(EL), resolution and LWR under DUV light and EUV exposure. We will also use DUV light to explore the impact of DUV contrast on the RLS relationships in EUV performances. We have measured Eth and LWR in DUV patterning process and correlated them with those obtained in EUV process. By using DUV light source we have setup EUV resist pre-screening and improving method.

Analysis of molecular resist distribution in a resist film by using x-ray reflectivity

To obtain high resolution and sensitivity and low line width roughness (LWR), the resist film homogeneity is thought to be the key requirement of extreme ultraviolet lithography (EUVL) resist materials. We have synthesized of a new class of chemically amplified molecular glass resists containing rigid triphenolic cores which are protected by flexible side chains. We analyzed the electron density distribution of resist films (70 nm) by using X-ray reflectivity (XRR). The effects of protection ratio, high and low activation protecting groups, chain lengths have been tested using selected molecular resist. We discuss the effects of the chemical structures of new molecular resists on EUV lithographic performances.