Effect of strain in PbSe/ZnPc stacked layers prepared by thermal evaporation method

摘要

The article investigates the structural and optical properties of ZnPc/PbSe hybrid multilayer (HML) structure deposited by using thermal evaporation technique. The X-ray diffraction pattern reveals the formation of ZnPc–PbSe composite and strain induced quantum size effect. Scanning electron microscope image shows the spherical grains for as-deposited film and nanorod like structure for the annealed film. The rods are oriented along one direction and stacking axis changes with the function of annealing temperature. The optical spectra show strong absorption in UV–Visible region and the optical absorption edge was red shifted for annealed samples. The luminescence properties were enhanced with broad emission in the range of 375–400 nm in HMLs. The optical band gap values are calculated and it varies from 3.2 to 3.04 eV with the function of annealing temperature and the band gap splitting was observed for a higher temperature of annealed samples. Strain-induced effect on ZnPc/PbSe HML has been reported using Raman spectra.