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Low Temperature Metalorganic Chemical Vapor Deposition of Semiconductor Thin Films for Surface Passivation of Photovoltaic Devices

Published online by Cambridge University Press:  23 May 2016

Sneha Banerjee
Affiliation:
ECSE Department, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY-12180, U.S.A.
Rajendra Dahal
Affiliation:
ECSE Department, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY-12180, U.S.A.
Ishwara Bhat*
Affiliation:
ECSE Department, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY-12180, U.S.A.
*
*(Email: bhati@rpi.edu)
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Abstract

Three II-VI wide bandgap compound semiconductors have been investigated for surface passivation of various photovoltaic devices. First part of this work focuses on the surface passivation of HgCdTe IR detectors using CdTe. A new metalorganic chemical vapor deposition (MOCVD) process has been developed that involves depositing CdTe films at much lower temperature (< 175°C) than the conventional processes used till now. Deposition rate as high as 420nm/h was obtained using this novel experimental setup. Favorable conformal coverage on high aspect ratio HgCdTe devices along with a significant minority carrier lifetime improvement was obtained. Another II-VI semiconductor, namely, CdS was investigated as a surface passivant for HgCdTe IR detectors. It was deposited by MOCVD as well as atomic layer deposition (ALD) and was studied for optimal conformal coverage on high aspect ratio structures. Surface passivation of p-type Si wafer has also been demonstrated using p-ZnTe grown by MOCVD, for possible application in solar cells. Preliminary work showed a remarkable improvement in the minority carrier lifetime of Si light absorbing layer after passivation with a thin layer of ZnTe.

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Articles
Copyright
Copyright © Materials Research Society 2016 

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References

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