నైరూప్య

Annealing temperature effect on properties of chemically deposited PbTe films and bulk

Ghassan Nashed

The PbTe films were deposited onto glass substrate (microscopic slices) by a chemical bath method (CBD) at room temperature. The deposited films are dense, smooth, and uniform with silver gray metallic luster structure. Using XRD, it found that the structure of PbTe possesses stable face centered cubic (fcc) phase. The grain size of the PbTe bulk increased within the range of 33– 57 nm with annealing temperature increasing.AFM micrographs of surface of the prepared film are observed that horizontal distance in the rang (230– 395) nm. The band gaps of the PbTe are determined from UV-Vis spectrophotometer and are found to be within the range (0.39 - 0.95) eV. Energy band gab of PbTe which determined from FT -IR spectrophotometer is (0.36ev). The activation energy varied from0.35- 1.72 eV for films and from0.11-0.34 eV for bulk with annealing temperature variations from 373-573K. Films and bulk exhibit p-type conduction and resistivity in the range (75×10-4&!. cm - 146×10-4Ù.cm). The carriers density and Hall mobility in PbTe bulk were in the rang 5.8 ×1023 m-3 and 4.004 m2/Vs.