Chemical Bath Deposition of PbS:Hg2+ Nanocrystalline Thin Films

Nanocrystalline PbS thin films were prepared by Chemical Bath Deposition (CBD) at 40 +/- 2 degrees C onto glass substrates and their structural and optical properties modified by in-situ doping with Hg. The morphological changes of the layers were analyzed using SEM and the X-rays spectra showing growth on the zinc blende (ZB) face. The grain size determined by using X-rays spectra for undoped samples was found to be similar to 36 nm, whereas with the doped sample was 32-20 nm. Optical absorption spectra were used to calculate the E-g, showing a shift in the range 1.4-2.4 eV. Raman spectroscopy exhibited an absorption band similar to 135 cm(-1) displaying only a PbS ZB structure.