Cadmium Telluride (CdTe) is one of the promising photovoltaic materials for solar cell. The post deposition treatment is important to improve the structural, electrical and optical properties of the CdTe thin films. Hence comparative study between the thermal annealing and laser annealing was carried out is this study. The analysis portrayed important features of both the thermal annealing and laser annealing processes and both of them improved the film quality. The films were deposited by radio frequency magnetron sputtering in high vacuum condition for 90 minutes at a growth temperature of 300°C. The CdTe thin films were then subjected to post deposition thermal and laser annealing independently. Thermal annealing was done for 15 minutes at a temperature of 400°C in vacuum condition. Laser annealing was done by illuminating the films with laser beam of 532nm wavelength with laser output energy of 60J/pulse, frequency of 10Hz and stage velocity of 0.5mm/sec. The structural analysis from XRD showed improvement in crystallinity for both the annealing process. Topography images revealed that thermal annealing reduced the surface roughness by improving the grain size. Optical analysis showed that the films had good absorbance within the visible range and the band gap ‘Eg’ for the as-grown and annealed films was approximately 1.5eV. Electrical analysis revealed that the bulk concentration improved after laser annealing and the resistivity reduced after thermal annealing was performed on the CdTe thin films.
COMPARATIVE STUDY OF THERMAL ANNEALED AND LASER ANNEALED CDTE THIN FILMS GROWN BY RF MAGNETRON SPUTTERING
AGHAEI, MOHAMMADREZA;
2015-01-01
Abstract
Cadmium Telluride (CdTe) is one of the promising photovoltaic materials for solar cell. The post deposition treatment is important to improve the structural, electrical and optical properties of the CdTe thin films. Hence comparative study between the thermal annealing and laser annealing was carried out is this study. The analysis portrayed important features of both the thermal annealing and laser annealing processes and both of them improved the film quality. The films were deposited by radio frequency magnetron sputtering in high vacuum condition for 90 minutes at a growth temperature of 300°C. The CdTe thin films were then subjected to post deposition thermal and laser annealing independently. Thermal annealing was done for 15 minutes at a temperature of 400°C in vacuum condition. Laser annealing was done by illuminating the films with laser beam of 532nm wavelength with laser output energy of 60J/pulse, frequency of 10Hz and stage velocity of 0.5mm/sec. The structural analysis from XRD showed improvement in crystallinity for both the annealing process. Topography images revealed that thermal annealing reduced the surface roughness by improving the grain size. Optical analysis showed that the films had good absorbance within the visible range and the band gap ‘Eg’ for the as-grown and annealed films was approximately 1.5eV. Electrical analysis revealed that the bulk concentration improved after laser annealing and the resistivity reduced after thermal annealing was performed on the CdTe thin films.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
