Recent progress in thin‐film cadmium telluride solar cells

Abstract

Cadmium telluride (CdTe) with a room‐temperature bandgap energy of 1.45 eV has been shown to be the most promising low‐cost, thin‐film photovoltaic material for terrestrial applications. Significant progress has been made during the past several years, and thin‐film CdTe solar cells of > 1 cm2 area with conversion efficiencies higher than 12% have been prepared by several techniques. Thin‐film CdTe photovoltaic modules with 10% efficiency have also been produced. They are of the heterojuntion configuration using a transparent conducting semiconductor (TCS) as the window and p‐CdTe as the absorber. In this paper, the potential window materials for thin‐film CdTe solar cells are discussed. Thus far, cadmium sulphide (CdS) with a bandgap energy of 2.42 eV at room temperature has been found to be best suited for efficient CdTe solar cells. the deposition techniques for p‐CdTe films capable of producing efficient solar cells, including close‐spaced sublimation (CSS), electrodeposition, screen printing and spraying, are briefly reviewed, and the characteristics of the resulting solar cells are discussed. It is concluded that the efficiency of thin‐film CdTe solar cells can be increased to 18‐19% in the near‐term, leading to 15‐16.5% efficient modules.

Spray-on Thin Film PV Solar Cells: Advances, Potentials and Challenges

“…Large-area CdS/CdTe solar cells have been made by spraying of CdTe onto the surface of CdS/SnO/glass structures, followed by heat treatment. This is regarded as a low-cost technique amenable to continuous processing and automation [63].…”

RBS Analysis of Zinc Telluride Thin Films by Electron Beam Evaporation Technique

“…The alpha particles with energy of 3.5 MeV were used to perform the RBS analysis [5] of the samples with an integrated charge. The scattering angle is to be set at Ɵ of 165˚ referring to the beam direction.…”

Development of high-efficiency, thin-film CdTe solar cells. Final subcontract report, 1 February 1992--30 November 1995

“…For a 1.44 eV bandgap material, if the recombination at the interface and in the bulk can be reduced, over 900 mV open-circuit voltage (Vd can be attained [23,24]. Combining the above practically attainable cell parameters, J, and V, , it is possible to achieve 18% efficient polycrystalline CdTe solar cells [17,22]. However, there is a big gap between current and achievable CdTe cell efficiency because the efficiency …”

“…In this research, a Hitachi S-800 SEM system was utilized to investigate the CdTe/CdS structure in order to (a) observe the changes in the microstructure and grain size of polycrystalline CdTe layers after various chemical and heat treatments to correlate the structure to the device performance; and to (b) determine the crystallhity of the CdTe films grown under different substrates and growth conditions. A beam voltage of [15][16][17][18][19] kV with a beam current of 10 PA was used in the SEM measurements.…”