Electron Beam Nanolithography Using PMMA and Metal Halide Resists

Very high resolution (1-100 nm) lithography has been made possible by the advent of Scanning Transmission Electron Microscopy, which utilizes a .5 nm, 100 keV electron beam probe to expose high resolution resists on thin film substrates. This thesis presents investigations of PMMA and metal halide resists, and development of techniques that allow the fabrication of nanoscale structures. Patterns with feature sizes as small as 10 nm can be exposed in PMMA. Comparisons are made between measured and calculated absorbed energy distributions in PMMA. Replication of high resolution patterns with PMMA resist is also demonstrated using 30 keV protons. Electron Energy Loss Spectroscopy of self-developing metal halide resists reveals the intermediate states of these materials as a function of irradiation dose. In situ fabrication of high resolution structures is shown to be possible with these metal halide resists at feature sizes approaching 1 nm. Finally, replication of high resolution patterns into thin and thick substrates and direct writing of metal lines is demonstrated.