Studying the Segregation Induced Resist Component Contribution to EUV Stochastic Failures

Abstract

Extreme Ultraviolet (EUV) technology is necessary for chip manufacturing technology for finer circuits into many components for building faster and more energy-efficient chips. The EUV process utilizes a plasma light source that emits 13.5 nanometers in wavelength to create higher resolution chip circuit designs to transfer an aerial image at smaller dimensions for advanced process nodes at lower exposure doses. Chemically amplified resists have been recently commercialized as it benefits higher resolution chip circuit designs. However, one of the issues concerning EUV technology is that it can suffer from different types of stochastic defects due to photon shot noise, random inhomogeneities, and non-random inhomogeneities. This study investigates the potential non-random stochastic effects that exist in the multicomponent resist. In the multicomponent resist, self-segregation occurs, creating an inhomogeneous distribution leading to failures in the resist. We approached this problem by looking at previous models of the phase diagram to understand the system and energetic favorability of segregation. Throughout our experiments we explore balancing the ratios of solvent, polymer, and PAG and hoping to define the line where we reach the 2-phase region indicating we have reached segregation. First, we observed phase segregated regions using AFM through a spin coating method and a drop coat method. Then we approached the issue by analyzing the bulk liquid. Although we were unable to find the exact parameters where we cross the 2-phase region, through several formulations we have narrowed down the region that segregation occurs.