X光吸收光譜研究銅鉻氧化物之電子與原子結構

Electronic Structure of Delafossite Oxides of CuCr1-xO2(0≦x≦0.1) Studied by X-ray Absorption Spectroscopy

楊力達(Li-Ta Yang)

指導教授 ： 彭維鋒

淡江大學/理學院/物理學系碩士班/碩士(2012年)

https://doi.org/10.6846/TKU.2012.00645

摘要

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。

關鍵字

X 光吸收光譜 ； 銅鉻氧 ； 銅鐵礦

並列摘要

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.

並列關鍵字

X-ray absorption ； CuCr1-xO2 ； Delafossite

參考文獻

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