Abstract
Unlike optical systems, electron-charging effect is a concern for e-beam lithography. Accumulated charge on the resist will perturb the route of incident electrons, resulting in pattern distortion or failure. Therefore, reducing charge accumulation becomes an important topic for high-pattern-density e-beam applications. In this paper, we used a conductive material as the resist substrate for charging effect evaluation. The e-beam source from CD-SEM (Critical Dimension SEM) was initially used to conductive performance qualification. When comparing with non-conductive BARC, we found that the experimental conductive material has an additional 11% to 14% resist-shrinkage than a non-conducting BARC. However, we cannot repeat this phenomenon in the multiple-e-beam (MEB) imaging tool. From Monte Carlo simulation, the electrons deeply penetrate through the substrate instead of being trapped in the resist substrate. It further indicates that although conductive bottom layer can dissipate electron effectively for surface charging, the film scheme as well as tool grounding are also important for minimizing the charging effect. © 2011 SPIE.