非晶As_2S_3半导体薄膜在激光作用下的性能及结构研究

Changes of Properties and Structure in Amorphous As_2S_3 Semiconductor Films Induced by Light Illumination

在激光辐照或退火作用下 ,As2 S3非晶半导体薄膜的光学吸收边出现红移现象 ,并且随着激光功率的增大和辐照时间的延长 ,红移值增大 ,并最后达到饱和。这种红移在先经过退火处理再激光辐照的薄膜中是可逆的。从扫描电镜的形貌图中也可以看出 ,经激光辐照后 ,薄膜表面有晶相出现 ,且随着激光功率的增加 ,晶相出现增多。As2 S3非晶半导体薄膜中光致效应的产生是由于光致结构变化所致 ,对其产生原因 。

The optical absorption edges of amorphous As 2S 3 films shifted to lower energy with band gap light illumination or annealing near the glass transition temperature. The magnitude of red shift increased with the increase of the intensity of illumination light and the time of illumination and became saturated finally. The red shift in well annealed As 2S 3 film was reversible. Photocrystallization was also observed in the illuminated As 2S 3 films with scanning electron microscope (SEM) measurements and the crystal phase was more with higher intensity of illumination light. The photoinduced effects in amorphous As 2S 3 films were ascribed to photostructural changes and the change mechanisms are discussed in this paper.