The structure and growth of thin films of lead sulphide condensed in vacuum on to amorphous substrates and their systematic dependence on film thickness, residual gas pressure and residual gas composition

Abstract

Surface structures at a series of thicknesses were determined by high energy electron diffraction at grazing incidence of the electron beam and in films up to 1000 AA thick by electron microscopy. Four distinct regions of crystal orientation as a function of film thickness and residual gas pressure are identified and discussed and the relationship between the angle of vapour incidence and the orientation axis is considered. The development of orientations as a consequence of surface atomic mobility, face development and subsequent twinning of the growing crystals is discussed and the influence of the residual gases on the growing films is also considered.