Temperature Dependence Of Energy States And Band Gap Broadening

Statistical analysis of energy levels is carried out. The density of surface states of MIS structures based on silicon is investigated. A mathematical model is constructed for the temperature dependence of the spectrum of the density of surface states for a wide energy range. A formula is derived for the density of surface states as a function of temperature. The thermal contributions of the expanded bands to the band gap of the semiconductor are taken into account. The resulting formula allows one to determine the density of energy states in the forbidden band in an explicit form, without taking into account the influence of the broadening of the allowed bands. This improves the accuracy of determining the concentration of impurities and defects in silicon.

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Electronic Characterization of Solid Surfaces: Determination of the energy levels of electrons at surfaces is now possible over a wide energy range

Science ◽

10.1126/science.178.4058.275 ◽

1972 ◽

Vol 178 (4058) ◽

pp. 275-282 ◽

Cited By ~ 72

Author(s):

H. D. Hagstrum

Keyword(s):

Energy Range ◽

Energy Levels ◽

Solid Surfaces ◽

Wide Energy Range ◽

Wide Energy

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Effects of Processing on Structural Defects in Silicon

MRS Proceedings ◽

10.1557/proc-36-199 ◽

1984 ◽

Vol 36 ◽

Author(s):

L. J. Cheng

Keyword(s):

Temperature Dependence ◽

Band Gap ◽

Valence Band ◽

Polycrystalline Silicon ◽

Energy Levels ◽

Structural Defects ◽

Significant Shift ◽

Twin Boundaries ◽

Phosphorus Diffusion ◽

P Type

ABSTRACTIt is found that the recombination activities of dislocation complexes and structural defects decorating twin boundaries in as-grown, p-type cast polycrystalline silicon have no observable temperature dependence in the range of 100–300 K, but the activities of these defects in phosphorusdiffused samples decrease with the increase of temperature in the same range. The results suggest that the phosphorus diffusion can cause a significant shift of energy levels of these defects toward the valence band from the middle of the band gap.

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DLTS study of 3C-SiC grown on Si using hexamethyldisilane

MRS Proceedings ◽

10.1557/proc-622-t4.3.1 ◽

2000 ◽

Vol 622 ◽

Author(s):

M. Kato ◽

M. Ichimura ◽

E. Arai ◽

Y. Masuda ◽

Y. Chen ◽

...

Keyword(s):

Activation Energy ◽

Deep Level Transient Spectroscopy ◽

Defect Density ◽

Deep Level ◽

Energy Levels ◽

Wide Energy Range ◽

Defect Level ◽

Wide Energy ◽

Transient Spectroscopy ◽

Relationship Of

ABSTRACTn-type 3C-SiC was heteroepitaxially grown on n-type Si(100) substrates using HMDS (hexamethyldisilane) and characterized by DLTS (deep level transient spectroscopy) measurements. In order to investigate relationship of defect density with epilayer thickness, epilayers with various thicknesses were grown. Relatively thin (<1.0μm thick) epilayers were found to contain defects with energy levels distributed in a wide energy range, while relatively thick (>2.2μm thick) epilayers contain a defect with an activation energy of 0.25eV. This defect level is slightly shallower than that in 3C-SiC grown by SiH4 and C3H8 (∼0.3eV).

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Study of (p,n) Reaction in a Wide Energy Range

Asian Journal of Research and Reviews in Physics ◽

10.9734/ajr2p/2019/v2i430107 ◽

2019 ◽

pp. 1-18

Author(s):

N. A. El-Nohy ◽

M. N. El-Hammamy ◽

S. Diab ◽

A. M. El-Shinawy

Keyword(s):

Elastic Scattering ◽

Optical Model ◽

Energy Levels ◽

Model Potential ◽

Wide Energy Range ◽

Microscopic Approach ◽

Density Dependent ◽

Wide Range ◽

Optical Model Potential ◽

Wide Energy

In this paper, the quasi-elastic scattering (p, n) reactions are studied for a wide range of target nuclei 13C, 14C, 48Ca, 90Zr and 208Pb and different incident energies (35-160 MeV). The phenomenological Optical model potential and density independent approaches are used for these calculations in comparison with density dependent semi-microscopic approach. The density dependent parameters are modified to achieve the best calculations for many targets at different energy levels.

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Temperature Dependence of the Density of States and the Change in the Band Gap in Semiconductors

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a9980.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 4383-4386

Keyword(s):

Temperature Dependence ◽

Band Gap ◽

Anomalous Temperature Dependence ◽

High Concentration ◽

Anomalous Temperature ◽

Density Spectrum ◽

Absorption Of Light ◽

Energy States ◽

The Mathematical Model ◽

Model Temperature

The temperature dependence of the density of energy states in semiconductors has been studied. Strong doping with impurities with deep levels broadens the conduction band and the valence band. This enhances the absorption of light below the red border. Consequently, a possible change in the width of the forbidden zone. In this paper, using the mathematical model, temperature dependence of the density spectrum of states, changes in the band gap are shown by analyzing the density spectrum of energy states, an explanation of the anomalous temperature dependence in acceleration semiconductors is proposed, the effects of doping with a high concentration on the band gap of the semiconductor are investigated. Explained absorption in the range of 0.6-0.9 eV for silicon

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Energy Levels and Electromagnetic Transition of 90-94mo Nuclei Using Ibm-1

10.32792/utq/utjsci/vol7/2/32 ◽

2020 ◽

pp. 149-152

Keyword(s):

Experimental Data ◽

Transition Probability ◽

Energy Levels ◽

Dynamical Symmetry ◽

Interacting Boson Model ◽

Excitation Energies ◽

Electromagnetic Transition ◽

Boson Model ◽

Energy States ◽

Good Agreement

The energy states for the J , b , ɤ bands and electromagnetic transitions B (E2) values for even – even molybdenum 90 – 94 Mo nuclei are calculated in the present work of "the interacting boson model (IBM-1)" . The parameters of the equation of IBM-1 Hamiltonian are determined which yield the best excellent suit the experimental energy states . The positive parity of energy states are obtained by using IBS1. for program for even 90 – 94 Mo isotopes with bosons number 5 , 4 and 5 respectively. The" reduced transition probability B(E2)" of these neuclei are calculated and compared with the experimental data . The ratio of the excitation energies of the 41+ to 21+ states ( R4/2) are also calculated . The calculated and experimental (R4/2) values showed that the 90 – 94 Mo nuclei have the vibrational dynamical symmetry U(5). Good agreement was found from comparison between the calculated energy states and electric quadruple probabilities B(E2) transition of the 90–94Mo isotopes with the experimental data .

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