1School of Physics and Microelectronics Science, Hunan University, Changsha 410082 2College of Material and Engineering, Hunan University, Changsha 410082 3Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082
Optical Characteristics of La-Doped ZnS Thin Films Prepared by Chemical Bath Deposition
1School of Physics and Microelectronics Science, Hunan University, Changsha 410082 2College of Material and Engineering, Hunan University, Changsha 410082 3Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education and State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082
摘要Undoped and La-doped ZnS thin films are prepared by chemical bath deposition (CBD) process through the co-precipitation reaction of inorganic precursors zinc sulfate, thiosulfate ammonia and La2O3. Composition of the films is analyzed using an energy-dispersive x-ray spectroscopy (EDS). Absorption spectra and spectral transmittances of the films are measured using a double beam UV-VIS spectrophotometer (TU-1901). It is found that significant red shifts in absorption spectra and decrease in absorptivity are obtained with increasing lanthanum. Moreover, optical transmittance is increased as La is doped, with a transmittance of more than 80% for wavelength above 360 nm in La-doped ZnS thin films. Compared to pure ZnS, the band gap decreases and flat-band potential positively shifts to quasi-metal for the La-doped ZnS. These results indicate that La-doped ZnS thin films could be valuably adopted as transparent electrodes.
Abstract：Undoped and La-doped ZnS thin films are prepared by chemical bath deposition (CBD) process through the co-precipitation reaction of inorganic precursors zinc sulfate, thiosulfate ammonia and La2O3. Composition of the films is analyzed using an energy-dispersive x-ray spectroscopy (EDS). Absorption spectra and spectral transmittances of the films are measured using a double beam UV-VIS spectrophotometer (TU-1901). It is found that significant red shifts in absorption spectra and decrease in absorptivity are obtained with increasing lanthanum. Moreover, optical transmittance is increased as La is doped, with a transmittance of more than 80% for wavelength above 360 nm in La-doped ZnS thin films. Compared to pure ZnS, the band gap decreases and flat-band potential positively shifts to quasi-metal for the La-doped ZnS. These results indicate that La-doped ZnS thin films could be valuably adopted as transparent electrodes.
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2011, Vol. 28 
