非晶态As2S8半导体薄膜的光致结构变化效应研究

实验研究了非晶态As2S8半导体薄膜在光照、退火-光照和退火-光照-退火-光照关连作用下的光折变效应及淀积态与退火态两种膜系光致体积变化现象.采用棱镜耦合技术、Raman光谱和X线衍射测试技术,确认了As2S8薄膜经紫外光辐照后薄膜密度增高、折射率增大的现象.实验表明,淀积态As2S8薄膜经紫外光照后,折射率变化的最大增量可达到0.06,而退火态As2S8薄膜经紫外光照射后,其折射率最大变化比前者要小一个数量级,约为0.005 7.淀积态和退火态两种膜系紫外光照后,体积缩小,这与As2S3非晶态薄膜的情况不同,体积变化率分别为－3.5%和－2.1%.实验还显示,退火态的As2S8薄膜存在折射率完全可逆现象.

Study on Photoinduced Structural Changes Effect of Amorphous Semiconductor As2S8 Film

The undergo changes in the refractive index and the photoexplansion of amorphous semiconductor As2S8 film under illuminating, annealing-illuminating and annealing-illuminating-annealing-illuminating are stadied expermentally. The increase in refractive index and density for As2S8 film after ultraviolet illumination is found through application of a prism coupler technique, X-ray diffraction spectra and Raman spectra. The results demonstrate that the refractive index changes after illumination for a deposited As2S8 film is one order of magnitude greater than for an annealed As2S8 film, and they are ~0.06 and ~0.005 7, respectively. The photoexplansions of the deposited and annealed As2S8 film are distinct with the As2S3 film decreased, －3.5% and －2.1%, respectively. The experimental data shows that the full reversible photorefractive phenomenon is found in an annealed As2S8 film.