الفهرس 
Introduction
Theoretical approachOnly 14 pages are availabe for public view
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Abstract
This thesis is dedicated to the study of some physical properties of MnBiSb alloys and thin films where the alloys were prepared by conventional melting technique and thendeposited in the form of a thin film by thermal evaporation technique. the X -ray diffraction patterns of these alloys and thin films found that all the peaks belong to Bi Mn Sb phases. the XRD results showes that the crystal structure of the ternary phase with the composition MnBiSb.6.1 Sample preparation
MnBi1-xSbx alloys and thin films (x=0.05, 0.10, 0.15, 0.20& 0.25 at. %). were prepared by conventional melting technique . Components were placed in vacuum quartz tubes and treated with special thermal treatments. Then MnBi1-xSbx was deposited by thermal evaporation with different composition and thicknesses for MnBi0.95Sb0.05 by thermal evaporation using a coating unit (Manufactured using Technology Licensed from Edwards Ltd, Auto 306), alloys have been deposited on glass substrate .
6.2 Structure analysis
For bulk compositions, XRD patterns of the MnBi1-xSbx with x = 0.05, 0.10, 0.15, 0.20, & 0.25 at. %, showed that all the peaks belong to Bi, Mn2Sb, MnSb and Mn-Bi-Sb phases. the appearance of Mn2Sb, MnSb and MnBiSb phases point to the completion of the reaction between the elements Mn, Bi, and Sb. Thus, we can describe the crystal structure of the ternary phase with the composition Mn-Bi-Sb as hexagonal P63/mmc group, the second phase Mn2Sb associated with the tetragonal P4/n mm (129) and the bismuth phase allied hexagonal R-3m (166).
The crystallite sizes are found to be in the range of 206.496 to 314.480 nm. The crystallite sizes increase with increasing Sb content .In addition, the strain ε increases with increasing Sb (-9.035 x 10-4 to -2.455 x 10-4 from x= 0.05 to 0.25) .This is consistent with the reported results that the lattice shrinking arised due to Sb doping.
Clearly, the grain sizes observed by the SEM are several times larger than those calculated by the XRD, indicating that each grain determined by the SEM is composed of several crystallites.
For thin films, also we deduced that the crystal structure of the the formed Mn-Bi-Sb ternary phase is the p63/mmc group, the second phase Mn2Sb associates with the tetragonal P4/n mm(129) and the bismuth phase allied hexagonal bismuth phase R-3m(166 ).
The average crystallize size of the thin films using the Scherrer’s equation were tabulated found to be in the range of 9.7 - 14.7 nm.
The grain size of the granules is the largest at the lowest concentration (x= 0.05), then decreases to reach the smallest value at x= 0.15, then increases again. The grain size observed by SEM is a fraction of a micrometer and turns out to be larger than the crystallizes calculated by XRD, indicating that each grain determined by SEM is composed of several crystals.
For MnBi0.95Sb0.05 thin film with different thicknesses (d= 25, 50, 75 nm) ,it was found that all existed peaks belong to Bi, Mn, Mn2Sb, MnBi, and Mn-Bi-Sb phases. The crystal structure of the ternary phase , the second phase Mn2Sb and the allied bismuth phase as previously explained.