Morphological and structural effects of excimer laser treatment of amorphous silicon

The excimer laser irradiation of thin film amorphous silicon (a-Si) precurs ors on glass is a suitable method for obtaining high-performance polycrysta lline silicon (p-Si) active layers for devices and circuits. By changing th e experimental conditions, the recrystallization method generates a variety of microstructures that have direct impact on the material performance. An additional reason for microstructural characterization is introduced by the methods for spatially locating the recrystallization nuclei, used in mo re ergonomic concepts of device fabrication. Metal and SiO2 strip overlayers have been applied here, on a-Si to fix the position of the solidification seeds after laser melting. The control of many aspects of the thin film microstructure can be achieved with a collection of a few inspection techniques like AFM, SEM, EC contras t, TEM, X-ray diffraction (XRD), some of which require preliminary grain de coration treatment, and some do not. The results of different irradiation experiments, are herein illustrated, e nlightened by the above characterization techniques, for providing informat ion on surface morphology, grain arrangement, preferred orientation. 2000 E lsevier Science Ltd. All rights reserved.