Band Gap Modulation of the IV, III鈥揤, and II鈥揤I Semiconductors by Controlling the Solid Size and Dimension and the Temperature of Operation

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• 作者：Yuming Chen ; Jianwei Li ; Xuexian Yang ; Zhaofeng Zhou ; Chang Q Sun
• 刊名：Journal of Physical Chemistry C
• 出版年：2011
• 出版时间：December 1, 2011
• 年：2011
• 卷：115
• 期：47
• 页码：23338-23343
• 全文大小：844K
• 年卷期：v.115,no.47(December 1, 2011)
• ISSN：1932-7455

文摘

From the perspectives of the energy band theory, the bond order-length-strength correlation, the local-bond-averaging approach, and the core鈥搒hell configuration for nanostructures, we have reconciled the effect of solid dimension and temperature of operation on the band gap of semiconductors by formulating the band gap as a function of the Hamiltonian and its perturbation by the response of the length and energy of the representative bond to the sample dimensionality and the applied temperature. Theoretical reproduction of the observations of Si, Ge, GaN, AlN, ZnO, ZnSe, and ZnS crystals confirmed that the size tunability of the band gap originates from the skin-region local bond relaxation and the associated quantum entrapment of binding energy. The extent of the E_G change depends on the tunable fraction of the undercoordinated atoms in the skin up to two atomic layers in depth. The temperature dependence of the band gap arises from bond expansion and weakening, with the opposite trends to that induced by size reduction. Furthermore, modeling reproduction of the temperature dependence has led to quantification of the atomic cohesive energy and Debye temperature of the specimen.