Polycrystalline films of CdS, CdSe, and CdTe up to 104 AA thick were condensed on to polished stainless steel substrates initially at room temperature in residual air at pressures from 5*10-3 to 10-7 Torr, at normal and oblique vapour incidence. Surface structures at a series of film thicknesses were determined by high-energy electron diffraction. Randomly disposed hexagonal crystals were observed up to a thickness H, at the surfaces of films condensed at residual air pressure p after which strong (0001) orientation was developed in the further deposition. At normal incidence H was approximately 1000 AA for p=5*10-3 Torr, and H rose with decrease in p, up to approximately 1500 AA at 5*10-7 Torr.

Polycrystalline films of PbSe and PbTe up to 104 AA thick were condensed at 15 to 300 AA s-1 in residual air at 10-3 to 10-8 Torr pressure on to glass and polished stainless steel substrates, initially at room temperature, at normal and oblique vapour incidence. Surface structures were determined by high-energy electron diffraction at a series of film thicknesses. Distinct regions of different crystal orientation are identified dependent on film thickness, residual gas pressure and composition, deposition rate and the nature of the source material. The relationship between the angle of vapour incidence and the tilt of the orientation axis is also established. The influence of the experimental parameters on the development of the different orientation regions is discussed and the results are compared with similar results from PbS films.

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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.