Crystallization of Silicon on Electro-Optic Plzt by a Laser Beam Modulated in Shape and Intensity Profile

Abstract

AbstractPLZT, a ferroelectric material with a high quadratic electro-optic coefficient, is combined with silicon technology via chemical vapor deposition to enable the realization of Si/PLZT spatial light modulators. Laser crystallization is required to produce device quality silicon deposited on PLZT. The critical issues in the laser crystallization are (i) achieving crystallization in the absence of a good seed, and (ii) preventing damage to the PLZT. To prevent PLZT damage during the laser heating, a 3.5 μm silicon dioxide layer is used as a thermal buffer between the silicon and the PLZT and the effective scanning time is shortened to 100 μs. A double humped cw argon ion laser with a shaped beam is used to achieve successful crystallization with good surface smoothness and large grain size. This technology and devices fabricated on these samples will be discussed.