An Alternative Device Structure for High Efficiency As Doped CdTe Photovoltaics

The work on As doped CdTe polycrystalline (pX) photovoltaics (PV) has yielded some high efficiency devices. All of these PV devices contain As in the bulk of the Cd(Se)Te absorber. The possibility of defect formation in pX CdTe thin films is not entirely understood, except for studies performed on monocrystalline CdTe and theoretical calculations on the same. In this study, we propose an alternate device structure and doping method to dope only the back surface of CdTe with As. This is to form a better ohmic contact without doping the bulk of the absorber and mitigating defects, to improve the open circuit voltage (V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">oc</inf>) and power conversion efficiency.