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.

Download full-text


Available from: Kevin Peter O'Donnell, Jun 13, 2014
  • Source
    • "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. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The energy flux in bipolar semiconductors is investigated taking into account the influence of recombi-nation on it. The general expression of an energy flux in a nondegenerate semiconductor is obtained in a linear approximation with respect to perturbation taking into account recombination (the presence of nonequilibrium charge carriers in the semiconductor) and thermal electrical currents of electrons and holes. The energy flux density has been calculated in two different cases, the case of weak recombi-nation and the case of strong recombination, for a one-dimension case.
    International Journal of Heat and Mass Transfer 01/2016; 92:430-434. DOI:10.1016/j.ijheatmasstransfer.2015.09.005 · 2.38 Impact Factor
  • Source
    • "The temperature dependencies of the series resistance R s , the effective bandgap energy E g ⁎ and the integrated EQE are presented in Fig. 3. It can be seen (Fig. 3b) that in the temperature region from room temperature to T = 180 K, E g ⁎ follows the model of temperature dependence of the bandgap energy proposed by K.P. O'Donnell and X. Chen [29]. Then E g ⁎ starts to decrease with further decreasing of the temperature until the " critical " temperature at about 40 K where the rapid increase of E g ⁎ starts. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Quaternary semiconductor compound Cu2ZnSnS4 (CZTS) is a promising non-toxic absorber material for solar cells made from earth abundant elements. In this study temperature dependencies (T = 10–300 K) of current–voltage (J–V) characteristics and external quantum efficiency (EQE) spectra of CZTS monograin layer solar cells were measured in order to clarify current transport in CZTS that is still not fully understood. Three different temperature ranges can be distinguished from the temperature dependence of the series resistance (Rs) obtained from J–V measurements and the effective bandgap energy (Eg⁎) determined from the EQE spectra. Thermally activated conductivity, Mott's variable-range hopping conductivity, and very low temperature (< 40 K) blocking of the interface recombination were observed.
    Thin Solid Films 05/2015; 582. DOI:10.1016/j.tsf.2014.10.069 · 1.76 Impact Factor
  • Source
    • "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] "
    [Show abstract] [Hide abstract]
    ABSTRACT: The elemental composition, structural, optical and electronic properties of p-type Cu3BiS3 thin films are investigated. The films are shown to be single phase orthorhombic, with a measured composition of Cu3.00Bi0.92S3.02. A surface oxidation layer is also clarified using energy dependent X-ray microanalysis. Photoreflectance spectra demonstrate two band gaps (EgX =1.24 eV and EgY =1.53 eV at 4 K) associated with the X and Y valence sub-bands. The photocurrent excitation measurements suggest a direct allowed nature of EgX. Photoluminescence spectra at 5 K reveal two broad emission bands at 0.84 and 0.99 eV quenching with an activation energy of 40 meV.
    Energy Procedia 12/2014; 60. DOI:10.1016/j.egypro.2014.12.359
Show more