Document Type |
: |
Thesis |
Document Title |
: |
Characteristics of some phases from In -Te system growing with a special design based on Bridgman technique خصائص بعض الأطوار من النظام انديوم _ تليريوم المنماة بواسطة تصميم خاص اعتماداً على تقنية بريجمان |
Subject |
: |
Electricity |
Document Language |
: |
Arabic |
Abstract |
: |
Research on binary semi conducting compound formed by elements from groups (III) and (VI) of the periodic table as a collective group of materials have been and are still the subject of much intensive investigation.
In the last few years widespread attention has been paid to the semi conductors of the AIIIBVI group. Great attention has been paid to the Ga, In, and Te chalcogenides. In particular the study of the A2IIIB3VI , A2IIIB5VI and A4IIIB3VI compounds is quite attractive .
Indium tellurides are useful as materials for electronics and for optical recording. Single crystals of In2Te5 grown by modified Bridgman technique .High efficiency, low cost, simple design constructed locally in our laboratory was used for grown In2Te5 single crystal. The product ingot was identified with X-ray analysis. An investigation was made on the Hall effect , electrical conductivity and thermoelectric power as well as switching effect .The investigated samples were P-type conducting. The Hall coefficient yields a room temperature concentration of 1.3X1014cm-3.
The band gap was found to be ΔEg =0.88 eV, the ionization energy ΔEa were estimated as 0.14 eV . RH at room temperature was 4.6X104 cm3/Coul. Hence , a combination of the electrical conductivity and Hall effect measurements enable us to study the influence of temperature on the Hall mobility and to discus the scattering mechanism of the charge carriers also the present investigation involves thermoelectric power measurements of In2Te5 single crystal ; These measurements enables us from The determination of many physical parameters such as carriers mobilities , effective masses of free charge carriers , diffusion coefficients and diffusion lengths, relaxation time of electrons and holes. As well as the figure of merit. The switching phenomena of our In2Te5 monocrystal was studied. Current – controlled negative resistance (CCNR) in In2Te5 single crystal have been observed for the first time. It has been found that In2Te5 exhibits memory switching the result strongly indicated that the phenomenon in our sample is very sensitive to temperature, light intensity and sample thickness.
The current – voltage characteristics is symmetrical with respect to the reverse of the applied voltage and current. The switching parameters were checked under the influence of different factors of the ambient condition.
This mode of investigation, (crystal growth and transport properties as well as switching phenomenon) is the ideal way for finding out the possibility of making application for this compound, especially in the field of energy conversion, devices and electronic engineering |
Supervisor |
: |
. Nagat Tawfeek Abbas |
Thesis Type |
: |
Master Thesis |
Publishing Year |
: |
1430 AH
2009 AD |
Number Of Pages |
: |
251 |
Added Date |
: |
Thursday, September 12, 2013 |
|
Researchers
خيرية عبدالله ال قحيم | Quhim, Khyriah Abdullah | Investigator | Master | |
|