خواص لایه های رسوب نشانی شده CdTe به روش تبخیر باریکه الکترونی

Properties of CdTe films deposited by

electron beam evaporation

خواص لایه های رسوب نشانی شده  CdTe به روش تبخیر باریکه الکترونی 

ABSTRACT

Cadmium telluride thin films were prepared by electron beam evaporation on glass substrates kept at different temperatures in the range 30 - 300 °C. The films were characterized by X-ray diffraction, scanning electron microscopy and optical absorption measurements. The conductivity of the films was measured in the temperature range 100 - 300 K. While the low temperature data (100 - 200 K) could be explained by the variable range hopping process, the high temperature data (200 - 300 K) could be explained on the basis of Seto's model for thermionic emission of the carriers over the grain boundaries. Transmission spectra have indicated a direct band gap around 1.55 eV.

 

روش جدید سنتز لایه های نازک ZnO: ریزساختار، خواص الکتریکی و اپتیکی

New process for synthesis of ZnO thin films: Microstructural, optical

and electrical characterization

روش جدید سنتز لایه های نازک ZnO: ریزساختار، خواص الکتریکی و اپتیکی

ABSTRACT

Zinc oxide (ZnO) is an interesting wide-band-gap semiconductor material with a direct band gap of 3.36 eV [1] at room temperature and exciton binding energy of 60 meV. It has crystalline structure of the wurtzite type and the unit cell with the constants a = 3.24 ˚A and c = 5.19A˚ . Thin films of ZnO are utilized for a wide variety of electronic and opto-electronic applications, such as surface acoustic wave devices [4], transparent conducting electrodes [2], heat mirrors [3]. Nanoscale porous structures of ZnO with a high surface area find their application in chemical sensors [5] and dye-sensitised solar cells [6]. Various techniques have been used to deposit undoped and doped ZnO films on different substrates, including spray pyrolysis [7], organometallic chemical vapor deposition [8], pulsed laser deposition [9], sputtering [10], and sol–gel process [11].