The formation of well-defined crystalline structures by UV laser irradiation of amorphous silicon films

TL;DR

This paper investigates how UV laser irradiation transforms amorphous silicon films into crystalline and cone-like structures, revealing the process of crystalline network formation and morphological evolution under laser exposure.

Contribution

It provides new insights into the laser-induced crystallization process and morphological changes in amorphous silicon films in the presence of oxygen.

Findings

Formation of crystalline silicon oxide network

Development of cone-like structures with laser dose

Persistence of nanowire remnants after morphological changes

Abstract

This study provides a new insight into the processes which occur when thin film hydrogenated amorphous silicon is subjected to UV laser irradiation in the presence of oxygen. It achieves this by observing the effects of subjecting the films to progressively increasing laser radiation doses. This reveals that an array of nuclei is first created, leading to the formation of a well-defined crystalline network, consistent with the structure of silicon oxide. Further irradiation results in the formation of cone-like structures on the crystalline network, due to silicon-oxygen bond breakage and migration of the resultant silicon-rich material. Eventually the cone-like structures become the dominant features, but remain interconnected by nanowire remnants of the original crystalline structure.