Ultra-fast laser-induced recrystallization of amorphous silicon films

Summary form only given. The pulsed laser-induced recrystallization of thin semiconductor films on amorphous substrates can have major potential applications in the fabrication of thin film transistors (TFTs) for high-definition active matrix liquid displays. For nanosecond pulses, the process is driven by rapid melting and resolidification. The associated heat transfer and phase-change thermodynamics have been studied by a variety of in situ diagnostics of nanosecond temporal resolution, including time-resolved optical transmission, reflection, multi-wavelength emission, and transient electrical conductance measurements. It was found that the recrystallized material structure critically depends upon the laser fluence (i.e. the pulse energy per unit surface area) and the melt quench rate which is determined by the heat loss to the substrate.The objective of the present work is to identify and investigate the fundamental mechanisms of phase-transformations at extremely fast rates. To accomplish this, 100 nm-thick amorphous silicon (a-Si) films deposited by low-pressure chemical-vapor deposition.