The Effect of Quantum Dot on the Optical Absorption Coefficient of Copper Gallium Diselenide

• Main Authors: Lee, Chia-Hsun, 李佳勳
• Other Authors: Lin, Pang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/60184244708919277669

碩士 === 國立交通大學 === 材料科學與工程學系 === 98 === Improvement of photovoltaic power conversion efficiency is always the key issue in the solar cell research and development. Quantum dots, as one of the promising improvement methods, in the thin film can be applied due to the generation of impact-ionization effect, Auger recombination and miniband. In this work, co-sputtering of quantum dots on copper gallium diselenide layers via target-attach sputtering method was performed. Four various materials are utilized as our quantum dots, including PbS, InSb, GaSb and CuInSe2. This study is mainly focused on the difference of physical properties of the thin film depending on the doping of quantum dots and annealing. The instruments for characterizing the effect of quantum dots are described as follows. X-Ray Diffraction (XRD) determines the crystal quality and grain size. Raman Spectroscopy analysis detects the quality of thin film. Cross section Scanning Electron Microscope (SEM) image is applied to calculate deposition rate in the various environments to ensure the same thickness of the as-prepared films. Energy-Dispersive X-ray Spectroscopy (EDX) results characterize the element ratio of thin films. Real size of quantum dots is determined by TEM image. UV-Vis Spectroscopy analysis is conducted to compute the absorption coefficient of thin films.