FABRICATION OF NANOMETER SCALE STRUCTURES.

The first step in fabricating structures on the nanometer scale by pattern transfer techniques is to identify and characterize materials that exhibit high resolution when exposed to a focused electron beam and that can be used as a 'resist' against etching or removal of the underlying substrate. The authors' investigations have centered on the polymer polymethylacrylate (PMMA) and various metal halides, some of which are directly beam vaporizable. The results presented were obtained in a VG Microscopes Ltd, Model HB5 Scanning Transmission Electron Microscope (STEM) equipped with a 12-bit resolution pattern generator and a microcomputer-controlled energy-loss spectrometer. Exposure is usually carried out at 100 keV with a probe diameter of 0. 5 nm and a current of 10** minus **1**2 minus 10** minus **1**0 amp.