Abstract

Many samples of amorphous silicon germanium thin films had been fabricated using vacuum thermal deposition technique. Some of the samples are deposited on glass substrates; the others are on Si wafers. The effect of annealing temperature and germanium quantity on the structural and optoelectronic properties are studied and explained. The results obtained from X-ray diffraction show that films are deposited as amorphous structure. The films deposited on glass o substrate start polycrystalline transformation at annealing temperature around 600 C, while the others deposited on Si o o wafer start the transformation near to 655 C and with best results at 830 C. Increasing the germanium quantity from x= 0 to x= 0.3 leads to the reduction of optical energy gap. The behavior of x=0.3 germanium sample gives, somewhat, better quantum efficiency, higher photogenerated current with reasonable output voltage, but higher leakage current. The quantum efficiency tends to decrease with the increase of the wavelength λ and the absorption coefficient α increases with the increase of the quantity of Ge.

Keywords
Amorphous Silicon Germanium, a-SiGe/a-Si, Solar Cell, Optical Energy Gap, Quantum Efficiency, Annealing Temperature, Absorption Coefficient, Urbach Energy
How to Cite this Article?
Mohamad, W.F., Al-Tikriti, M.N., and Altrabsheh, B. (2017). Crystallization and Optoelectronic Propertiesof a-SiGe/a-Si Solar Cell. i-manager's Journal on Electronics Engineering, 7(2), 1-7.
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