Copper single crystals subjected to a neutron dose of 3×1018 nvt (total flux) at pile temperature have been examined after deformation by the following experimental techniques: (a) observation of the load-extension relationships, (b) investigation of the slip-line structure with the electron microscope, and (c) diffraction electron microscopy of thinned-down single crystals before and after deformation. The critical resolved yield stress is in the order of 1.6 kg/mm2. In the early stages of deformation, the load-extension curves show serrations which are as large as 1.0% of the critical resolved shear stress. In the linear portion of the stress-strain curve, the rate of work hardening is less for irradiated single crystals than for the nonirradiated. The stress-strain curves of the irradiated and the nonirradiated specimens are similar in the parabolic region of the curves. The slip-line structure, at low deformations, consists of fine slip lines that are clustered together; the distances between the slip lines are, on the average, 100 A and often less; the distances between the clusters are in the order of 4μ. This structure is quite different than the alpha-brass structure, which in the past had been considered typical for irradiated copper. Cross slip, which is most abundant in the linear hardening region of the stress-strain curve, is found to be orientation dependent. The slip-line structures for the irradiated and nonirradiated crystals at high strains are very similar. Prismatic dislocation loops, apparently resulting from the condensation of vacancies, are found to be the most frequently produced radiation defect. The interaction between loops and glide dislocations results in heavily kinked dislocations which are probably responsible for the observed high yield stress. The glide dislocations were seen to remove the radiation damage. Because of this cleaning out of radiation-produced defects and the ability of the dislocations to multiply from new sources, the prolonged ``easy glide range'' can be explained. Further, the proposed mechanism provides an explanation of the work hardening in the linear and parabolic parts of the stress-strain curve.

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Minority-carrier diffusion lengths on both sides of the CuxS/CdS heterojunction in polycrystalline thin-film solar cells were determined from the decay of the short-circuit current generated by a 20-keV electron beam traversing the junction. The measured diffusion lengths in the low-field regions of these cells ranged from 0.11 to 0.57 μm for electrons in the p-type cuprous sulfide and from 0.07 to 0.31 μm for holes in the n-type cadmium sulfide. Uncertainties introduced by surface recombination effects, internal fields, and experimental accuracy specified that the actual bulk diffusion lengths could range from 0.09 to 1.71 μm for minority electrons in the cuprous sulfide and from 0.06 to 0.44 μm for minority holes in the cadmium sulfide. Measurement and analysis errors were estimated to cause bulk diffusion lengths to differ from measured values by less than the worst case limits of +200 and −31%.

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The structure of a thin layer of copper sulfide produced by treating cadmium sulfide with a solution of cuprous chloride was investigated by electron diffraction and transmission electron microscopy. Results show that this copper sulfide layer is composed of chalcocite, Cu2S, and is epitaxial to the cadmium sulfide. No diffraction spots from other copper sulfide phases (such as djurleite, etc.) were observed. Accurate determination of chalcocite lattice spacing was made by using in‐situ cadmium sulfide as standard and Moiré fringes measurements.