SYNERGY EFFECT OF XRD, RAMAN, FTIR, UVVIS AND TEM ANALYSES IN μc-Si:H AND nc-Si MICROSTRUCTURE DETERMINATION

摘要

Tandem solar cells based on a-Si:H/μc-Si:H double- or triple-junction technology are very important for silicon thin film approach in order to enhance the efficiency of the cells especially convenient for the residential systems. Because for such systems the μc-Si:H and nc-Si materials have substantial importance, it is necessary to create them as good as possible. In order to obtain the required information about the structural and optical properties of the μc-Si:H and nc-Si films, X-ray diffraction, TEM, Raman and FTIR spectroscopies and UVVis spectrophotometiy have to be used. In this study, a-Si:H, μc-Si:H films 300-350 nm in thickness and SiO_2/a-Si:H multi-layers 600-650 nm in thickness were deposited by PECVD on Coming glass and crystalline silicon substrates to find out the influence of silane dilution with hydrogen in μc-Si:H films and a-Si:H sub-layer thickness in SiO_2/a-Si multi-layered films on the micro-structural and optical properties of the films. The study was focused on the synergy effect of the above mentioned experimental techniques when the more detailed micro-structure changes in the films were carried out and the results were confronted with the optical parameters of the films as spectral refractive indices and absorption coefficients.