• Healy, N.
• Peacock, Anna C.
• Martinez, G.
• Franz, Y.
• Zisis, G.

Abstract

The strong absorption of c.w. laser radiation in the green/blue spectral region has been used to thermally anneal and locally crystalize small volumes of amorphous silicon (a-Si) which has been thermally insulated from the environment. We will present experimental results for two distinct cases where this method has been used for producing high quality c-Si and secondly for allowing additional optoelectronic functionality to be built into the material.  <br/>More specifically we will discuss laser annealing results obtained in cylindrical and planar geometries; in a-Si core optical fibers and in a-Si thin films deposited on fused silica slabs and on the polar faces of LiNbO₃ single crystals. In both geometries crystallization of a-Si has been achieved, in some cases producing crystallites with enormous aspect ratios. In the case of a-Si core fibers we have not only achieved a significant improvement of the optical quality of the silicon material, but also observed some tuneability of its optoelectronics properties. LiNbO₃ on the other hand is one of the cornerstone platforms of nonlinear/integrated optics. By transferring the materials processing advances made in our silicon fibers to LiNbO₃, we can envisage a platform that exploits the superior optical and electronic properties of both materials for the development of high performance optoelectronic devices. Our preliminary results are very encouraging and we believe that this combination promises many exciting future applications.

Topics

• impedance spectroscopy
• single crystal
• amorphous
• thin film
• Silicon
• annealing
• crystallization