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The Rutherford backscattering technique using 1-MeV protons has been employed to analyze pure and doped lead azide thin films of various thicknessess which had been prepared by vacuum evaporation followed by vapor conversion. The films were found to be approximately homogeneous in composition with depth within the limits of the depth resolution of the experiment. The energy rate loss dE/dx of the films was found to be about 60 keV/μm. The Tl-doped films showed a somewhat different backscattering spectrum from the undoped films.

The far and near infrared absorption of thin films of pure and doped lead azide are reported. The effects of thallium and bismuth doping were investigated. The far ir lattice modes are essentially unaffected by doping; the near ir intra-azide ion modes are markedly affected by Tl doping. These effects are related to changes in the electronic properties with doping and are attributed to azide vacancies which compensate for, and pair with, substitutional Tl acceptors.