本論文主要以X 光吸收光譜及價帶光電子能譜實驗研究銅鐵礦透 光半導體CuCr1-xO2(0≦x≦0.1)的電子與原子結構。此實驗主要研究 當鉻缺 (x≠0)時，一系列不同含量之樣品在導帶以及價帶上傳輸性質 之變化與機制研究。由延伸X 光吸收精細結構(X-ray absorption fine structure，EXAFS)之量測上發現當鉻缺變大時，系列樣品之原子結 構沒有顯著變化，X 光吸收近邊緣結構(X-ray absorption near edge structure，XANES)則顯示了鉻缺陷會使得銅離子由Cu+轉變為Cu2+ 而產生電洞，由價電帶光電子能譜上也顯示出當鉻缺會使得Cu 3d-O 2p 之間的軌域混成增加，我們也可以得知系列樣品之載子傳遞方式 是在Cu 3d 與O 2p 之間傳導電子；電洞與軌域混成增加之變化皆利 於增加樣品之導電能力，進而增加半導體的傳導效率。 We have investigated the electronic and atomic structures of delafossite CuCr1-xO2 (0≦x≦1) system. No significant changes in local atomic structure of CuCr1-xO2 were observed by extended x-ray absorption fine structure (EXAFS). X-ray absorption near edge fine structure (XANES) shows that the valence state of Cu increased from Cu1+ to Cu2+ will create hole doping with decreasing Cr concentration. Valence band x-ray photoemission spectroscopy (VB-XPS) indicates the enhanced hybridization of Cu 3d-O 2p orbital. The data observed in XANES and VB-XPS suggest the carrier transport between Cu 3d and O 2p. Both the hole doping and enhanced hybridization of Cu 3d-O 2p are important for increasing the conductivity.
