The Epitaxy of Copper on Sapphire

Epitaxial twinned single-crystal films of copper have been grown on sapphire substrates by high vacuum evaporation in the temperature range 240–-375°C. The presence of a twin relationship in copper deposited on the basal plane of sapphire was demonstrated and evaluated by x-ray diffraction techniques. The epitaxy has been shown to be (111)Cu ∥ (0001)α−Al2O3; [21̄1̄)Cu ∥ [21̄1̄0]α−Al2O3. The films have been found to exhibit the bulk metal resistivity.