AVS 64th International Symposium & Exhibition
    Nanometer-scale Science and Technology Division Wednesday Sessions
       Session NS+MN+MS+SS-WeA

Paper NS+MN+MS+SS-WeA9
Characterization of Butyl Tin Photoresists for Nanoscale Patterning

Wednesday, November 1, 2017, 5:00 pm, Room 19

Session: Nanopatterning, Nanofabrication and 3D Nanomanufacturing
Presenter: Gregory Herman, Oregon State University
Authors: J.T. Diulus, Oregon State University
R.T. Frederick, Oregon State University
M. Li, Rutgers University
D. Hutchison, Oregon State University
M.R. Olsen, Oregon State University
I. Lyubinetsky, Oregon State University
L. Árnadóttir, Oregon State University
E.L. Garfunkel, Rutgers University
M. Nyman, Oregon State University
H. Ogasawara, SLAC National Accelerator Laboratory
G.S. Herman, Oregon State University
Correspondent: Click to Email
Inorganic photoresists are of interest for nanomanufacturing due the potential for high resolution patterning with low line edge roughness, while having high sensitivity to extreme ultraviolet (EUV) radiation. The combination of high absorption coefficient elements and radiation sensitive ligands can improve inorganic photoresist sensitivity while providing high contrast. Inorganic clusters are ideal candidates for photoresists since they have nanometer particle sizes with high particle size uniformity, and the ligand chemistries can be tuned for radiation induced chemistries that control relative solubility differences. In this presentation, characterization of a promising inorganic cluster-based EUV photoresist will be presented, where the goal of the studies is to better understand patterning mechanisms. In these studies, we are investigating butyl tin Keggin cluster that has recently been synthesized, and has shown promising properties as an inorganic photoresist. Key to these clusters, for application as an EUV photoresist, are the high EUV absorption coefficient for Sn, and the radiation sensitive carbon-tin bond. Removal of the organic ligand changes the polarity of the film, which provides the necessary solubility contrast for nanopatterning. We have used temperature programed desorption, electron stimulated desorption, and ambient pressure X-ray photoelectron spectroscopy to characterize both thermal and radiation induced processes in thin films formed from these clusters. We have found that butyl group desorption occurs through both thermal and radiation induced processes, and have determined both the carbon-tin bond strength and electron desorption cross-sections. Studies performed in different ambient conditions, and photon energies, have shown large effects on the radiation induced chemistries, where a significant enhancement in carbon decay was observed for O2 pressures up to 1 torr. These studies provide a means to better understand the radiation induced processes that result in the solubility contrast of these materials, and may guide in the development of improved EUV photoresists for nanolithography.