Sensitivity enhancement of the high-resolution xMT multi-trigger resist for EUV lithography

Abstract

Irresistible Materials is developing a new molecular resist system that demonstrates high-resolution capability based on the multi-trigger concept. A series of studies such as resist purification, developer choice,and enhanced resist crosslinking were conducted in order to optimize the performance of this material. The optimized conditions allowed patterning 14 nm half-pitch (hp) lines with a line width roughness (LWR) of 2.7 nm at the XIL beamline of the Swiss Light source. Furthermore it was possible to pattern 14 nm hp features with dose of 14 mJ/cm 2 with an LWR of 4.9 nm. We have also begun to investigate the addition of high-Z additives to EUV photoresist as a means to increase sensitivity and modify secondary electron blur.

High Sensitivity Resists for EUV Lithography: A Review of Material Design Strategies and Performance Results

“…Improvements on the design of these materials led to some excellent and very promising results in resolution, LWR-LER, and sensitivity. Resist formulations based on the multi-trigger concept showed capability to resolve 13.3 nm lines on 28 nm pitch, with 2.97 nm LWR and dose of 26 mJ/cm 2 as well as 14.7 nm lines on 30 nm pitch, with 2.72 nm LWR and dose of 34 mJ/cm 2 [ 80 , 81 , 82 , 83 , 84 ].…”

Novel concept for extreme-UV photoresist materials

“…3 In addition, our team at Irresistible Materials have developed a new material-the multitrigger resist-which represents an evolution of our chemically amplified molecular resists. 4 With this new approach, we can achieve high-resolution, high-sensitivity, and low-line-edgeroughness resists.…”

High-resolution EUV lithography using a multi-trigger resist

“…We have previously reported [1] an improvement in sensitivity and LER using enhanced versions of our baseline material. Results of NXE exposures in this resist system have also been presented.…”

“…The newly introduced Irresistible Materials (IM) multi-trigger resist concept [1] has been designed to address the trade-off relationship between sensitivity, resolution and LER. The multi-trigger concept employed in our system enables high sensitivity but also incorporates a quenching behaviour into the chemistry to improve resolution, and reduce the materials stochastics impact of a separate quencher.…”