Direct measurement of the band gap and Fermi level position at InN(11(2)over-bar0)
Direct measurement of the band gap and Fermi level position at InN(11(2)over-bar0)
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DOI：
10.1063/1.3553022
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发表时间：
2011-02-07
影响因子：
4
通讯作者：
Eisele, H.
中科院分区：
文献类型：
--
作者：
Ebert, Ph.;Schaafhausen, S.;Eisele, H.
用扫描隧道显微镜和光谱研究了在超高真空中新解理的非极性化学计量比InN（11（2）over bar 0）表面。由于带隙中不存在本征表面态，扫描隧道光谱直接产生基本的体带隙为0.7 +/- 0.1 eV。费米能级被钉扎在导带最小值以下0.3 eV，这是由于解理诱导的缺陷态。因此，对于该表面，可以排除固有电子积累。电子积累是由于表面污染或材料分解而引起的外在效应，而不是InN的内在材料性质。(C)2011年美国物理学会。[doi：10.1063/1.3553022]
A nonpolar stoichiometric InN(11 (2) over bar0) surface freshly cleaved inside UHV was investigated by scanning tunneling microscopy and spectroscopy. Due to the absence of intrinsic surface states in the band gap, scanning tunneling spectroscopy yields directly the fundamental bulk band gap of 0.7 +/- 0.1 eV. The Fermi energy is pinned 0.3 eV below the conduction band minimum due to cleavage induced defect states. Thus, intrinsic electron accumulation can be excluded for this surface. Electron accumulation is rather an extrinsic effect due to surface contamination or material decomposition, but not an intrinsic material property of InN. (C) 2011 American Institute of Physics. [doi:10.1063/1.3553022]