Recrystallization of Silicon-on-Insulator Structures by Sinusoidally-Scanned Electron Beams

Abstract

This paper describes the recrystallization by an electron beam of Si films deposited on SiO2/Si structures. To achieve pseudo-line-shaped heating, a spot beam was scanned along a line at frequencies of up to 10 kHz. It is predicted theoretically that the temperature profile along the line can be controlled by the scanning waveform and that a concave molten zone edge is obtained wih a sinusoidal scan. It was found experimentally that the recrystallization conditions required for forming a large single-crystal area with a flat surface are rather restricted in the sinusoidal-scan method, since the Si films are broken up or deformed by the temperature gradient along the line. It was also found that overlapping scans of the pseudo-line-shaped beam are effective in increasing the single-crystal area. A nearly single-crystalline Si film of 300×200 µm2 was produced on an SiO2/Si structure by overlapping scans.