Influence of the thiourea/CdCl2 concentration ratio used for the chemical bath deposition of CdS thin films, upon the CdS/CdTe interface recombination velocity in CdTe/CdS/glass structures.

Abstract

Modification of the optical reflectance spectra of epitaxial gallium arsenide by weak magnetic fields J. Appl. Phys. 112, 073513 (2012) Theoretical and experimental study of the optical absorption at longitudinal phonon or phonon-plasmon coupling mode energy: An example of GaN J. Appl. Phys. 112, 063531 (2012) Negative differential resistance associated with hot phonons J. Appl. Phys. 112, 063707 (2012) Photoluminescence properties and high resolution x-ray diffraction investigation of BInGaAs/GaAs grown by the metalorganic vapour phase epitaxy method J. Appl. Phys. 112, 063109 (2012) Optical properties of InGaPN epilayer with low nitrogen content grown by molecular beam epitaxyIn this work we study the influence of the thiourea/CdCl 2 concentration ratio used for the chemical bath deposition of CdS thin films on glass substrates, upon the CdS/CdTe interface recombination velocity in CdTe/CdS/glass structures, where the CdTe layer was grown on the CdS thin film by close space vapor deposition ͑CSVT͒-hot wall technique. The interface recombination velocity was measured by means of the photoacoustic ͑PA͒ technique in a heat transmission configuration, in which minority carriers are photoexcited at the CdTe layer after illumination through the substrate and the CdS thin film. For data processing, a theoretical model was developed for the generation of the PA signal. We show a reduction in the value of the recombination velocity respecting those obtained for samples where CdS was grown by CSVT, and we observe that a minimal value appears for a thiourea/CdCl 2 ratio in the CdS deposition solution equal to 5. These results show a good correlation with those of electrical measurements performed in solar cell devices.

Physics and chemistry of CdTe/CdS thin film heterojunction photovoltaic devices: fundamental and critical aspects

“…The decrease in efficiency was related to oxidation or chemical changes at the surface leading to changes in shunt resistance together with Cu segregation through the grain boundary of CdS and CdTe (Table 13). 480 The efficiency was reduced to 11.2 and 6.3% for CdS grown by CSVT, 481,482 due to the larger R s for CSVT-CdS compared to CBD-CdS solar cells. It was shown that sulfur enrichment in the CBD-CdS layer reduces carrier density at GBs.…”

“…It was shown that sulfur enrichment in the CBD-CdS layer reduces carrier density at GBs. 482 Thus, larger photoconductivity of the CBD-CdS layer may result in better FF. The spectral response indicated an efficient interface between CBD-CdS and CdTe compared to CSVT-CdS and CdTe, though J sc is almost same for both the solar cells.…”

Determination of CdTe bulk carrier lifetime and interface recombination velocity of CdTe/MgCdTe double heterostructures grown by molecular beam epitaxy

“…9) and using a CdS/CdTe heterojunction with an interface recombination velocity in the range of 10 3 cm/s-10 6 cm/s. 10,11 It has been reported that MgCdTe and CdTe form a type-I band edge alignment, 12 suggesting that MgCdTe is good for electron and hole confinement and is expected to reduce the surface recombination rate of CdTe. Recently, we reported the growth, structural, and optical properties of CdTe/MgCdTe double heterostructures (DHs) grown on InSb (001) substrates by Molecular Beam Epitaxy (MBE).…”

Structural and Optical Properties of Chemically Deposited CdS Thin Films

“…Cadmium sulfide (CdS) has been emerged as an important transparent conducting semiconductor for thin film CdTe and CuInSe 2 heterojunction solar cells [1][2][3][4]. Among all thin film deposition methods, chemical bath deposition (CBD) is the simplest one that offers great scope for large area fabrication.…”