This Small Business Innovation Research (SBIR) Phase I project aims to develop a new photoresist material with dual tones for micro-photolithography. Traditional photoresist material responds to radiations in either positive or negative tone respectively. In this project, a dual-tone photoresist material that responds to radiations in positive and negative tone simultaneously will be investigated. The concept is that the photoresist is only soluble in developer when halfway radiated, resulting in split or doubled patterns.
The broader/commercial impact of this project will be the potential to provide a cost-effective photoresist technology for enhanced resolution of micro-photolithography. Currently, the Argon Fluoride (ArF) photolithography has already reached its resolution limit. The double-patterning (DP) process offers higher resolution, but is generally complex and costly. The dual-tone technology is expected to extend ArF lithography to the resolution level of Extreme Ultraviolet (EUV) lithography with lower cost than that of the DP process.
Funded by the NSF SBIR Phase I program, Suntific Materials, Columbia, Missouri, broke the ground on research for dual-tone photoresist. Photoresist forms a thin coating on silicon wafers. Upon exposure to UV light, the thin coating is capable of forming images like those on the old-fashion negative films. Forming those images is the very first step of building electronic circuits on computer chips. Photoresist is obviously an extremely important material for the semiconductor industry. Current photoresist can only form either positive-tone or negative-tone images. Positive-tone images look like normal pictures, while black and white regions are reversed in negative-tone images. Suntific Materials is developing the next-generation photoresist that produces double images. The double images make twice as many transistors on a computer chip. In other words, flash drives will hold twice as many pictures with Suntific Materials' new technology. Computers will run faster as well. Developing such technology takes a few steps. The very first is to scientifically demonstrate that the new ideas actually work. Suntific Materials has just done that. The dual-tone photoresist produced encouraging double images. With the NSF SBIR Phase II funding, the company will produce test samples for the IC makers like Intel to try. The development of the technology will not only benefit the semiconductor industry, but stimulate the economy.
