Electronic structure of copper nitrides as a function of nitrogen content

THIN SOLID FILMS

卷:531

Article

Gordillo, N.^1,2  Gonzalez-Arrabal, R.²  Diaz-Chao, P.³  Ares, J. R.³  Ferrer, I. J.³  Yndurain, F.⁴  Agullo-Lopez, F.^3,5 

[1] UCM UPM, Madrid, Spain

[2] Univ Politecn Madrid, Inst Fus Nucl, ETSI Ind, E-28006 Madrid, Spain

[3] Univ Autonoma Madrid, Dept Fis Mat, E-28049 Madrid, Spain

[4] Univ Autonoma Madrid, Dept Fis Mat Condensada, E-28049 Madrid, Spain

[5] Univ Autonoma Madrid, Ctr Microanal Mat, E-28049 Madrid, Spain

关键词: Copper nitride;    Electronic structure;    Sebeeck coefficient;    Density functional theory;   

DOI  :  10.1016/j.tsf.2013.01.030

来源: Elsevier

【 摘 要 】

The nitrogen content dependence of the electronic properties for copper nitride thin films with an atomic percentage of nitrogen ranging from 26 +/- 2 to 33 +/- 2 have been studied by means of optical (spectroscopic ellipsometry), thermoelectric (Seebeck), and electrical resistivity measurements. The optical spectra are consistent with direct optical transitions corresponding to the stoichiometric semiconductor Cu3N plus a free-carrier contribution, essentially independent of temperature, which can be tuned in accordance with the N-excess. Deviation of the N content from stoichiometry drives to significant decreases from -5 to -50 mu V/K in the Seebeck coefficient and to large enhancements, from 10(-3) up to 10 Omega cm, in the electrical resistivity. Band structure and density of states calculations have been carried out on the basis of the density functional theory to account for the experimental results. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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