Surface photovoltage and modulation spectroscopy of E- and E+ transitions in GaNAs layers

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Article

Kudrawiec, R.^1,2  Sitarek, P.¹  Gladysiewicz, M.¹  Misiewicz, J.¹  He, Y.³  Jin, Y.⁴  Vardar, G.⁴  Mintarov, A. M.³  Merz, J. L.³  Goldman, R. S.⁴  Yu, K. -M.²  Walukiewicz, W.² 

[1] Wroclaw Univ Technol, Inst Phys, PL-50370 Wroclaw, Poland

[2] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA

[3] Univ Notre Dame, Dept Elect Engn, Notre Dame, IN 46556 USA

[4] Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48104 USA

关键词: Dilute nitrides;    Surface photovoltage;    Photoreflectance;    Contactless electroreflectance;   

DOI  :  10.1016/j.tsf.2014.07.052

来源: Elsevier

【 摘 要 】

Surface photovoltage (SPV) spectra were measured for GaN0.014As0.986 layers at room temperature and compared with room temperature photoreflectance (PR) and contactless electroreflectance (CER) measurements. Spectral features related to E- and E+ transitions were clearly observed in SPV spectra at energies corresponding to PR and CER resonances. In this way it has been shown that SPV spectroscopy is an alternative absorption-like technique to study both the E- and E+ transitions in dilute nitrides. The observation of E+ transition in SPV spectra means that it is a direct optical transition at the G point of GaNAs band structure which can be explained by the band anticrossing interaction between the localized states of N and the extended conduction band states of the GaAs host. (C) 2014 Published by Elsevier B.V.

【 授权许可】

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