Laser-Induced Lateral, Vertically-Seeded Epitaxial Regrowth of Deposited Si Films over Various SiO2 Patterns

Abstract

The difference in bridging epitaxy of Si over SiO₂ by pulse ruby laser and cw-scanned Ar laser irradiation has been investigated using TEM and SEM. Pulse laser induced lateral regrowth over SiO2 is governed by uniform heat flow from the oxide window edges to the SiO₂ center during a melting time of ∼100 ns. The regrowth length is limited to ∼2.5 µm and straight crystal boundary is formed in regrown layers when SiO₂ stripe patterns are used. On the other hand, when cw-scanning laser is utilized, single crystal film is formed without crystal boundary over the whole 5 µm width oxide stripe pattern.