Synthesis and characterization of chemically deposited lead selenide thin films

Lead selenide thin films have been deposited on glass substrate by a modified chemical bath deposition method (CBD). An aqueous alkaline bath consisting of lead nitrate, selenosulphate and tartaric acid as complexing agent was used. The preparative parameters like ion concentration, temperature, pH and stirring rate have been optimized for getting good quality thin films. The ‘as-deposited’ thin films were characterized by XRD, AAS, EDAX, SEM, optical absorption and thermoelectrical techniques. The growth of film was found to be ion-by-ion method. The films were reddish brown, uniform, well adherent to substrate, well defined grained and nearly stoichiometric in nature. XRD study confirms polycrystalline nature in FCC structure. The optical absorption spectrum showed an exponential edge. Room temperature electrical conductivity was of the order of 10−3 (Ω cm)−1. The film exhibits p-type conduction mechanism.