Metal chloride passivation treatments for CdTe solar cells

ABSTRACTThe traditional CdCl2 passivation of CdTe is expanded by adding other chlorides such as MgCl2, NaCl, and MnCl2 into the process through a two-step passivation procedure that combines closed space sublimation step with a vapor process. This allows the possibility of forming a highly doped field at the back of the device that could act as an electron reflector that could boost device performance by directing electrons back into the absorber layer and increasing the voltage while limiting recombination at the back of the device. The effects the two-step passivation process on device performance are characterized by current-voltage measurements, and by electroluminescence and laser-beam induced current images to show the degree of device uniformity. Additionally, capacitance voltage measurements are used to study doping density, depletion width, and possible formation of a field at the back of the device.

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The Influence of Stressing at Different Biases on the Electrical and Optical Properties of CdS/CdTe Solar Cells

MRS Proceedings ◽

10.1557/proc-668-h5.11 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 3

Author(s):

S. W. Townsend ◽

T. R. Ohno ◽

V. Kaydanov ◽

A. S. Gilmore ◽

J. D. Beach ◽

...

Keyword(s):

Anomalous Behavior ◽

Open Circuit ◽

Trap Level ◽

Doping Density ◽

Zero Bias ◽

Cdte Solar Cells ◽

Current Voltage ◽

Depletion Width ◽

Capacitance Voltage ◽

Iv Curves

ABSTRACTCadmium Sulfide/Cadmium Telluride (CdS/CdTe) devices are subject to stress under various biases. Striking differences are observed with the Current-Voltage, and Capacitance- Voltage measurements for cells degraded at 100°C in dark under forward (FB), open circuit (OC), and reverse (RB) biases. RB stress provides the greatest degradation, and the apparent doping density profile shows anomalous behavior at the zero bias depletion width. Thin films of CdS, both doped and undoped, with Cu are characterized with photoluminescence (PL). The PL spectra from the CdS films are correlated with the CdS spectra from stressed devices, revealing that Cu signatures in the CdS layer of stressed devices are a function of stress biasing. Device modeling using AMPS-1D produces IV curves similar to that in RB degraded devices, by only varying the trap level concentration in the CdS layer.

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Development of plasma enhanced closed space sublimation for the deposition of CdS:O in CdTe solar cells

2013 IEEE 39th Photovoltaic Specialists Conference (PVSC) ◽

10.1109/pvsc.2013.6744184 ◽

2013 ◽

Cited By ~ 2

Author(s):

D E Swanson ◽

S R Hafner ◽

W S Sampath ◽

J D Williams

Keyword(s):

Solar Cells ◽

Closed Space ◽

Cdte Solar Cells ◽

Closed Space Sublimation ◽

Space Sublimation

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CdTe Solar Cells at CEA / LETI

MRS Proceedings ◽

10.1557/proc-1210-q08-31 ◽

2009 ◽

Vol 1210 ◽

Author(s):

Sergio Bernardi ◽

Sébastien Renet ◽

Alain Million

Keyword(s):

Solar Cells ◽

Chemical Bath Deposition ◽

Experimental Work ◽

Borosilicate Glass ◽

Closed Space ◽

Present Communication ◽

Cdte Solar Cells ◽

Closed Space Sublimation ◽

Space Sublimation ◽

State Of Art

AbstractThe present communication will present the results obtained at CEA/LETI in Grenoble, France, in the frame of an experimental work finalized to directly test the criticalities and chances of this technology row. By means of Closed Space Sublimation (CSS) and Chemical Bath Deposition (CBD) processes, appropriate annealing treatments and specific CdTe-contacting procedures, we reached the state-of-art of this technology with about 15% conversion efficiency under standard illumination conditions in “superstrate” cells configuration both for structures deposited on 3 mm thick low-iron containing sodalime glass (SLG) and Borosilicate glass (BSG).

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