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Authors: Alla Srivani Asst. professor in Physics & Electronics, Dept of Nano Biotechnology, Acharya Nagarjuna University Guntur-Dt, AP , India Prof Vedam RamaMurthy Prof/HOD Dept of Physics&electronics TJ PS College, Guntur, AP, India. G VeeraRaghavaiah HOD, Dept of Computer Science, PAS College, Pedanandipadu, Guntur, A ,India Introduction: In the starting concept of the present work, the solid solutions belonging to CdxZn1-xSe II-VI Ternary Semiconductor Band Energy Gap have been investigated. Doping of Cd component in a Binary semiconductor like ZnSe and changing the composition of do pant has actually resulted in lowering of Band Energy Gap. Thus effect of do pant increases the conductivity and decreases the Band Energy Gap and finds extensive applications. The present investigation relates Band Energy Gap and Electro Negativity with variation of composition for CdxZn1-xSe II-VI Ternary Semiconductor. The fair agreement between calculated and reported values of Band Energy Gaps In CdSe and ZnSe Binary semiconductors give further extension of Band Energy Gaps for Ternary semiconductors. II-VI Ternary semiconductors, which consist of various elements, have widely ranging Physical properties. They have therefore many possible applications. The physical Properties which may vary, include band gaps, crystal lattice structures, electron and Hole mobilities, optical properties, thermal conductivity, and so on. By selecting appropriate II-VI Ternary semiconductor materials, it becomes possible to realize various devices, which cannot be achieved using the main elemental semiconductor material, silicon. It is therefore important to understand the physical properties of II-VI Ternary semiconductors and to know how to select appropriate materials for desired applicants. Explanation of these properties can be found in specialty books. Among many II-VI Ternary Semiconductor Compounds, which consist of more than two elements, only some show semiconductor properties. II-VI Ternary Semiconductor Compounds, which show semiconductor properties, have the following features according to Wilson's model. (i) The conductivity of the II-VI Ternary semiconductor is electronic. Ionic conductivity is excluded. (ii) II-VI Ternary Conductivity is largely increased as a function of temperature, Pressure, Do pant composition, Electric and Magnetic fields. (iii) II-VI Ternary Conductivity is very dependent on the kind of impurities and their concentrations II-VI Ternary Semiconductor Compound also has tetrahedral bonds but they include not only covalent bonds but also ionic bonds. This is because compounds are formed from different elements, which have different electro negativity. The present work opens new line of approach to Band Energy Gap studies in CdxZn1-xSe II-VI Ternary Semiconductor. Recently much attention is paid to the study of Ternary Semiconductor materials and their Alloys for Application in design of Heterostructures. The important of all physical properties of these compounds are currently moving in to focus. Application of these Ternary Semiconductor materials in Optical devices has high experimental level of investigation. More attention is paid to the study of these compounds including Cadmium, Zinc of II Group Selenide from VI Group. CdxZn1-xSe is most Important Ternary Semiconductor material with Arbitrary alloy between CdSe and ZnSe with Cd Composition ranging between 0 X values 0 0.20 0.27 0.33 0.56 1.00 Calculated as a function of as composition. Obtained results were found in good agreement compared with experimental and theoretical data in literature. We have considered CdxZn1-xSe ternary alloys as having cubic symmetry in our calculation for all the five systems to maintain Consistency and simplicity. We have replaced one, two and Three as atoms, respectively, by in to get the desired concentration of theoretical The band profiles and band gap values are in good agreement with the earlier theoretical works. The band gaps are smaller than the experimental values. The layout of this paper is given as followings: Objective: The main Objective of this paper is to calculate CdxZn1-xSe II-VI Ternary Semiconductor Band Energy Gap values Theoretical Impact: The following relation calculates band Energy Gap of CdxZn1-xSe Eg (CdxZn1-xSe)=1-x* Eg (CdSe)+x*Eg (ZnSe)+SQRT (Eg (CdSe)* Eg (ZnSe)*x*1-x Where: Eg=Band Energy Gap X=Cd Composition. Additivity: Eg (CdxZn1-xSe)=X*Eg (CdSe)+1-x*Eg (ZnSe). Where: Eg=Band Energy Gap X=Cd Composition Cd Composition ranges: 0.0 0.20 0.27 0.33 0.56 1.00 Compound CdxZn1-xSe Xvalues 0 0.20 0.27 0.33 0.56 1.00 1-X Values 1 0.8 0.74 0.68 0.44 0 Ter Eg 2.58 2.75 2.77 2.77 2.632 1.74 Additivity 2.58 2.41 2.36 2.31 2.11 1.74 Xvalues 0 0.20 0.27 0.33 0.56 1.00 Reported 2.62 2.4 2.32 2.28 2.09 1.71 Graphical representation: This graph represents Band Energy Gap values of CdxZn1-xSe. Doping of Cd component in a Binary semiconductor like ZnSe and changing the composition of do pant has actually resulted in lowering of Band Energy Gap. Thus effect of do pant increases the conductivity and decreases the Band Energy Gap Future Plans: 1) Current data set of values of CdxZn1-xSe II-VI 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 Band Energy Gap of CdxZn1-xSe II-VI Ternary Semiconductors with in the Composition range of (0 Results and Di scussion: Band Energy Gap is used for Electrical conduction of semiconductors. This phenomenon is used in Band Gap Engineering. The band structures of the alloys show similar features to that of bulk CdSe and ZnSe. 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Alloys, Band Energy Gaps, Band Gap Engineering, Binary Semiconductors, Composition, Cadmium, Doping, Electrical Conductance, Electronic properties, Se,
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