Temperature Dependence of Semiconductor Band Gaps

University of Strathclyde, Glasgow, G4 ONG Scotland, United Kingdom
Applied Physics Letters (Impact Factor: 3.3). 07/1991; 58(25):2924 - 2926. DOI: 10.1063/1.104723
Source: IEEE Xplore


The application of a simple three‐parameter fit to the temperature dependence of semiconductor band gaps is justified on both practical and theoretical grounds. In all trials the fit is numerically better than that obtained using the widely quoted Varshni equation. The formula is shown to be compatible with reasonable assumptions about the influence of phonons on the band‐gap energy. Approximate analytical expressions are derived for the entropy and enthalpy of formation of electron‐hole pairs in semiconductors.

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    • "l n0 þ l p0 ¼ Àe g0 [15] [17] [18]. Usually, the bandgap, e g , depends on the temperature [19]. Therefore, generally speaking, under conditions of spatially nonuniform temperature distribution the bandgap will be different in different points of the specimen and differ from its value in equilibrium, e g0 ¼ e g T 0 ð Þ. "
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    • "For the orthorhombic structure of Cu 3 BiS 3 we use the notations X and Y for the top two bands. The temperature dependencies of E gX and E gY were fitted with the expression introduced by O'Donnell and Chen [20] "
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