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This article describes the different mix and match writing strategies using both an optical deep ultraviolet (DUV) stepper (ASML/90) and an electron-beam (e-beam) system (LEICA VB6HR) with both positive and negative tone chemically amplified resists. These resists, mainly developed for DUV applications, have shown very good performance under e-beam exposure. Negative tone resists such as the Shipley XP90166 and UVN2, and positive tone resists such as the Shipley UVIII and UV5 have been optimized in terms of soft bake temperatures, postexposure bake temperatures, and development process. Resolutions in the range of 40–50 nm have been obtained using a 50 keV accelerating voltage. Delay time effect has been quantified and different behaviors under vacuum and in air have been pointed out.

Low activation energy resists are studied through two formulations representative of these systems, namely, Shipley 248 nm XP9493 and MCC 193 nm TER-1 resists. It is shown that their specific behavior can be easily demonstrated by using differential scanning calorimetry techniques at different steps of the lithographic process. As these resists present a low activation energy for their deprotection, the postexposure bake (PEB) is not necessary so a comparison between processes with and without a PEB step can be made. Processes without PEB are interesting as they allow deconvolution and an emphasis on different phenomena (evaporation, diffusion, and recompaction) which are of tremendous importance for chemically amplified resists. Finally, processes without PEB can allow a correlation of the mechanisms involved in the resists to lithographic performance.