The objective of this article was to study the resolution limits of different negative tone chemically amplified resists from both commercial and experimental formulations. Process optimization has been done on all samples and this work underlines the importance of the choice of bake temperature to push resists to their ultimate resolution. Furthermore, the influence of several compounds, such as the polymer matrix blend, molecular weight, and photoacid compound, is detailed to determine the influence of each parameter on the final formulation performance.

Chemical Amplification Resists (CAR) are now widely used in optical lithography since the introduction of the deep UV era. One advantage of the CARs is also their full compatibility with electron beam writing. This paper is focused on the development work of a negative tone resist. The influence of resist compounds such as polymer matrix composition and PAG size on diffusion and ultimate resolution is detailed. Finally the pattern transfer capabilities of a 30 nm isolated line into a polysilicon layer is presented.

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