No abstract

No abstract

Abstract. Thin films of PbS were deposited by chemical bath deposition (CBD) method under various molarities using lead acetate as Pb 2+ ion source, thiourea as S 2-ion source and ammonia as complexing agent at a fixed pH value of 9 under bath temperature of 333 K. Four different molarities of PbS thin films were prepared. The as-prepared films were characterized by using X-ray diffraction (XRD), X-ray fluorescence (XRF), EDX, field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Parameters like crystallite size, lattice constant, microstrain, dislocation density were calculated. Optical constants such as extinction coefficient, absorption coefficient were measured from absorption spectra. Studies show that average nanocrystallite size increases from14.2 nm to 18.1 nm as the molarity of the film increases. Optical studies reveal the decrease of band gap from 1.75 eV to 1.44 eV with increasing molarity of the film indicating higher electrical conductivity of the films.

Thin films of PbS were deposited by chemical bath deposition (CBD) method under various molarities using lead acetate as Pb2+ ion source, thiourea as S2- ion source and ammonia as complexing agent at a fixed pH value of 9 under bath temperature of 333 K. Four different molarities of PbS thin films were prepared. The as-prepared films were characterized by using X-ray diffraction (XRD), X-ray fluorescence (XRF), EDX, field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Parameters like crystallite size, lattice constant, microstrain, dislocation density were calculated. Optical constants such as extinction coefficient, absorption coefficient were measured from absorption spectra. Studies show that average nanocrystallite size increases from14.2 nm to 18.1 nm as the molarity of the film increases. Optical studies reveal the decrease of band gap from 1.75 eV to 1.44 eV with increasing molarity of the film indicating higher electrical conductivity of the films.

Chemically synthesized ZnS thin film is found to be a good x-ray radiation sensor. We report the effect of annealing on the x-ray radiation detection sensitivity of a ZnS thin film synthesized by a chemical bath deposition technique. The chemically synthesized ZnS films are annealed at 333, 363 and 393 K for 1 h. Structural analyses show that the lattice defects in the films decrease with annealing. Further, the band gap is also found to decrease from 3.38 to 3.21 eV after annealing at 393 K. Current-voltage characteristics of the films are studied under dark and x-ray irradiation conditions. Due to the decrease of lattice defects and band gap, the conductivity under dark conditions is found to increase from to , while that under x-ray irradiation increases from to . On the other hand, the x-ray radiation detection sensitivity of the films is found to decrease with annealing. This decrease of detection sensitivity is attributed to the decrease of the band gap as well as some structural and surface morphological changes occurring after annealing.

No abstract

No abstract

No abstract