Sensitivity and resolution capability of photoresist depend on various parameters, such as efficiency of photoacid generation, base strength, types and concentration of protection groups on a polymer, as well as lithographic process condition.We have prepared polymers containing different protecting groups and investigated their effects on the sensitivity, and eventually, on ArF resist photolithographic behavior. Also, several different photoacid generators (PAGs) and bases were employed to study the influence of them on the resist sensitivity. We have changed process condition, especially, bake condition to discuss the role of bake temperature on the photochemical efficiency of the resist. It was found that the diffusion of the photogenerated acid and bases is the most significant factor to determine resist sensitivity than others.The detailed results will be discussed in this paper.

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As the device design rule is continuously shrinking, line end shortening (LES) has grown to be one of the critical problems in 193nm photolithography. Among several factors causing LES, diffusivity of photo-generated acid seems to have the most profound effect. Also, diffusivity of base quencher produces equivalent effects on LES, but in the reversed way. Besides, post-exposure bake (PEB) condition is another key factor by affecting diffusion length of photo-generated acid. Low LES can be achieved by lowering PEB temperature or shortening its time. In this paper, we will discuss our experimental results to assess the determining factors of LES and suggest controllability of LES in ArF lithographic process.