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Literature review of Physical Properties of Ternary semiconductors

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             Investigation of AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap
                                               V.Rama Murthy & Alla.Srivani
                                                              Research Scholar
                                                        Rayalaseema University
                                                  P.G Department of Physics, 
                                                             T.J.P.S College
                                                                       Guntur-6 A.P India

Abstract: AlxGa1-xSb III-V Ternary semiconductor is very important as an x of a constituent in the semiconductor is going to have significant changes in calculating Physical Property like Band Energy Gap. These Ternary Compounds can be derived from binary compounds by replacing one half of the atoms in one sub lattice by lower valence atoms, the other half by higher valence atoms and maintaining average number of valence electrons per atom. The subscript X refers to the alloy content or concentration of the material, which describes proportion of the material added and replaced by alloy material. This paper represents the AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap values

Keywords: Band Energy Gap, Composition, Electro Negativity, Molecular weight, density, optical polarizability.

Introduction: 1) In this opening talk of AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap Electronegativity values of Ternary Semiconductors are denoted by symbols XM and XN and Band Energy Gap is denoted by Eg 2) Linus Pauling first proposed Electro Negativity in 1932 as a development of valence bond theory,[2] it has been shown to correlate with a number of other chemical properties. 3) The continuous variation of physical properties like Electro Negativity of ternary compounds with relative concentration of constituents is of utmost utility in development of solid-state technology. 4) In the present work, the solid solutions belonging to AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap have been investigated. In order to have better understanding of performance of these solid solutions for any particular application, it becomes quite necessary to work on the physical properties like Electro Negativity of these materials. 5) Recently no other class of material of semiconductors has attracted so much scientific and commercial attention like the III-V Ternary compounds. 6) Doping of Al component in a Binary semiconductor like GaSb and changing the composition of do pant has actually resulted in lowering of Band Energy Gap. 7) Thus effect of do pant increases the conductivity and decreases the Band Energy Gap and finds extensive applications 8) The present investigation relates Band Energy Gap and Electro Negativity with variation of composition for AlxGa1-xSb III-V Ternary Semiconductor. 9) The fair agreement between calculated and reported values of Band Energy Gaps of AlSb and GaSb Binary semiconductors give further extension of Band Energy Gaps for Ternary semiconductors. 10) The present work opens new line of approach to Band Energy Gap studies in AlxGa1-xSb III-V Ternary Semiconductor

Objective:

               The main Objective of this paper is to calculate AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap values

Purpose:

          The purpose of study is AlxGa1-xSb III-V Ternary Semiconductor Band Energy Gap and effect of concentration in Electro Negativity values of III-V Ternary Semiconductors to represent additivity principle even in very low concentration range. This paper includes Electro Negativity values of III-V ternary semiconductors and Band Energy Gap values in composition range (0<x<1).

Theoretical Impact: Formula: Eg=[28.8/(2(XM-XN)2)1/4*(1-f12/1+2*f12)]POWER (XM/XN)2

                 Where:f12=[4pN/3]*[aM12*r12]/M12
                                   

Electro Negativity values of Elemental Semiconductors:

Compound Al Ga As In P Sb N E.N value 1.5 1.8 2 1.7 2.1 1.9 3

Electro Negativity values of AlxGa1-xSb III-V Ternary Semiconductor

X value 0 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5

1-x value 1 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5

Compound AlxGa1-xSb

XM value 1.8 1.767479 1.75144 1.735547 1.719797 1.70419 1.688726 1.673401 1.658215 1.643168

XN value 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9

28.8/(2(XM-XN)2)1/4 28.75014 28.71249 28.69007 28.66534 28.63839 28.60929 28.57809 28.54488 28.50972 28.47268

ALPHA-M 110.32 107.563 106.1845 104.806 103.4275 102.049 100.6705 99.292 97.9135 96.535

RO-VALUES 5.62 5.48 5.41 5.34 5.27 5.2 5.13 5.06 4.99 4.92

M-VALUES 191.48 189.796 184.454 182.112 179.77 177.428 175.086 172.744 170.402 168.06

ALPHA-M*RO/M 3.237928 3.105678 3.114371 3.073186 3.032002 2.990818 2.949634 2.908451 2.867269 2.826087

TOTAL 4*PI*N 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24

1-(4PIN/3)*ALPHAM*RO/M 8.16E+24 7.83E+24 7.85E+24 7.75E+24 7.65E+24 7.54E+24 7.44E+24 7.33E+24 7.23E+24 7.13E+24

1+2*(4PIN/3)*ALPHAM*RO/M 1.63E+25 1.57E+25 1.57E+25 1.55E+25 1.53E+25 1.51E+25 1.49E+25 1.47E+25 1.45E+25 1.43E+25

1-phi12/1+phi12 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

28.8/(2(XM-XN)2)1/4*(1-phi12/1+2*phi12) 14.37507 14.35624 14.34503 14.33267 14.3192 14.30464 14.28905 14.27244 14.25486 14.23634

Eg value 10.93863 10.02923 9.613679 9.221879 8.852244 8.503304 8.173698 7.862167 7.567542 7.28874

X value 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1

1-x value 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0

Compound XM value 1.628256 1.613481 1.598839 1.58433 1.569953 1.555706 1.541588 1.527599 1.513737 1.5

XN value 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9

(2(XM-XN)2)1/4 1.012879 1.014327 1.015841 1.017418 1.019056 1.020754 1.02251 1.024323 1.026191 1.028114

28.8/(2(XM-XN)2)1/4 28.43381 28.3932 28.3509 28.30696 28.26146 28.21445 28.16599 28.11613 28.06494 28.01246

ALPHA-M 107.6195 107.374 107.1285 106.883 106.6375 106.392 106.1465 105.901 105.6555 105.41

RO-VALUES 4.85 4.78 4.71 4.64 4.57 4.5 4.43 4.36 4.29 4.22

M-VALUES 167.973 165.836 163.699 161.562 159.425 157.288 155.151 153.014 150.877 148.74

TOTAL 4*PI*N 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24 7.56E+24

1+2*(4PIN/3)*ALPHAM*RO/M 1.57E+25 1.56E+25 1.55E+25 1.55E+25 1.54E+25 1.54E+25 1.53E+25 1.52E+25 1.52E+25 1.51E+25

1-phi12/1+phi12 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

28.8/(2(XM-XN)2)1/4*(1-phi12/1+2*phi12) 14.21691 14.1966 14.17545 14.15348 14.13073 14.10722 14.08299 14.05807 14.03247 14.00623

Eg value 7.024758 6.774662 6.537587 6.312727 6.099336 5.896715 5.704218 5.521239 5.347217 5.181627

Doping of Al component in a Binary semiconductor like GaSb and changing the composition of do pant has actually resulted in lowering of Band Energy Gap.

Future Plans:

1) Current data set of Electro Negativity values of AlxGa1-xSb III-V Ternary Semiconductors and Band Energy Gap values include the most recently developed methods and basis sets are continuing. The data is also being mined to reveal problems with existing theories and used to indicate where additional research needs to be done in future. 2) The technological importance of the ternary semiconductor alloy systems investigated makes an understanding of the phenomena of alloy broadening necessary, as it may be important in affecting semiconductor device performance.

Conclusion:

1) This paper needs to be addressed theoretically so that a fundamental understanding of the physics involved in such phenomenon can be obtained in spite of the importance of ternary alloys for device applications. 2) Limited theoretical work on Electro Negativity values and Band Energy Gap of AlxGa1-xSb III-V Ternary Semiconductors with in the Composition range of (0<x<1). 3) Our results regarding the Electro Negativity values and Band Energy Gap of III-V Ternary Semiconductors are found to be in reasonable agreement with the experimental data

Results and Discussion:

Electro Negativity values of Ternary Semiconductors are used in calculation of Band Energy Gaps and Refractive indices of Ternary Semiconductors and Band Energy Gap is used for Electrical conduction of semiconductors. This phenomenon is used in Band Gap Engineering.

Acknowledgments. –

              This review has benefited from V.R Murthy, K.C Sathyalatha contribution who carried out the calculation of physical properties for several ternary compounds with additivity principle. It is a pleasure to acknowledge several fruitful discussions with V.R Murthy.

References:

1) IUPAC Gold Book internet edition: "Electronegativity". 2) Pauling, L. (1932). "The Nature of the Chemical Bond. IV. The Energy of Single Bonds and the Relative Electronegativity of Atoms". Journal of the American Chemical Society 54 (9): 3570–3582.. 3) Pauling, Linus (1960). Nature of the Chemical Bond. Cornell University Press. pp. 88–107. ISBN 0801403332 . 4) Greenwood, N. N.; Earnshaw, A. (1984). Chemistry of the Elements. Pergamon. p. 30. ISBN 0-08-022057-6. 5) Allred, A. L. (1961). "Electronegativity values from thermochemical data". Journal of Inorganic and Nuclear Chemistry 17 (3–4): 215–221.. 6) Mulliken, R. S. (1934). "A New Electroaffinity Scale; Together with Data on Valence States and on Valence Ionization Potentials and Electron Affinities". Journal of Chemical Physics 2: 782–793.. 7) Mulliken, R. S. (1935). "Electronic Structures of Molecules XI. Electroaffinity, Molecular Orbitals and Dipole Moments". J. Chem. Phys. 3: 573–585.. 8) Pearson, R. G. (1985). "Absolute electronegativity and absolute hardness of Lewis acids and bases". J. Am. Chem. Soc. 107: 6801.. 9) Huheey, J. E. (1978). Inorganic Chemistry (2nd Edn.). New York: Harper & Row. p. 167. 10) Allred, A. L.; Rochow, E. G. (1958). "A scale of electronegativity based on electrostatic force". Journal of Inorganic and Nuclear Chemistry 5: 264.. 11) Prasada rao., K., Hussain, O.Md., Reddy, K.T.R., Reddy, P.S., Uthana, S., Naidu, B.S. and Reddy, P.J., Optical Materials, 5, 63-68 (1996). 12) Ghosh, D.K., Samantha, L.K. and Bhar, G.C., Pramana, 23(4), 485 (1984). 13) CRC Handbook of Physics and Chemistry, 76th edition. 14) Sanderson, R. T. (1983). "Electronegativity and bond energy". Journal of the American Chemical Society 105: 2259 15) Murthy, Y.S., Naidu, B.S. and Reddy, P.J., “Material Science &Engineering,”B38, 175 (1991)