Randomness of Polymer Microstructure in the Resist Film as Shot Noise

Extreme ultraviolet (EUV) with a wavelength of 13.5 nm has already been mass-produced, but serious technical problems remain an important issue. One of them is the line edge roughness (LER) value for critical dimension (CD). Local variations such as intra-filed CD uniformity and LER are usually identified from the average CD calculated using top-down view observations. However, it is not possible to get an overall picture of LER. In this study, cross-section SEM was applied efficiently to visualize or quantify the basic behavior of the resist. In addition, the resolution limits and minimum structural units that make up the resist pattern associated with LER are discussed.