8 nm Wide Line Fabrication in PMMA on Si Wafers by Electron Beam Exposure

Abstract
The ultimate limit of electron beam lithography in practical samples, e.g., thick PMMA on bulk Si substrate, was investigated in both experiment and theory. For this, the nanometer electron beam lithography system (NSF-1) was used to perform nanometer structure patterning. Monte Carlo calculation with secondary electron generation included was done to simulate the experiment. Eight nanometer wide lines with 100 nm period were delineated in 230 nm thick PMMA on a bulk Si, probably attaining the ultimate limit of electron beam fabrication. This has also been supported by evaluation based on the Monte Carlo simulation.