Chemically deposited thin films of PbSe as an absorber component in solar cell structures

PbSe thin films were prepared by chemical deposition using dimethylselenourea as a source of selenide ions. Depending on the duration (30 min to 4 h) and temperature (30-60 degrees C) of the deposition, and the substrate, the films show a high degree of preferred orientation for the (111) planes. The texture coefficients could be up to 5 for these planes. The crystallite diameters are in the 30-35 nm range, and optical bad gap, 0.4-0.7 eV. The electrical conductivity is p-type, 0.01-10 (Omega cm)(-1). These films were deposited over CdS/Sb2S3 or CdS/Sb2Se3 solar cell structures as an additional absorber. In a CdS/Sb2Se3/PbSe cell, this addition increases the short circuit current density (J(sc)) from 0.2 mA/cm(2) to 8.9 mA/cm(2) and conversion efficiency (eta) from 0.04% to 0.99%. In a CdS/Sb2S3/PbSe cell, J(sc) is 5.91 mA/cm(2); eta, 0.98%; and open circuit voltage, 560 mV. (C) 2011 Elsevier B.V. All rights reserved.