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The composition, transparency, refractive index, and infrared reflectance of yttria-stabilized cubic hafnia (c-HfO(2)) single crystals were measured. The material is transparent from the ultraviolet to the mid-infrared and for 9.6-mol % Y(2)O(3), the index is slightly smaller than for comparable cubic zirconia c-ZrO(2) or for diamond, but the dispersion (n(F) - n(c) = 0.02811) is larger than that of diamond. The index vs wavelength from 0.36 microm in the ultraviolet to 5.0 microm in the infrared is represented by a three-term Sellmeier formula to 1 x 10(-4). The temperature dependence of refractive index is similar to that of c-ZrO(2). The infrared reflectance spectrum is fitted in a classical dispersion analysis with seven oscillators derived from the transverse optical phonon as well as acoustic frequencies with splittings due to lowered symmetry derived from the randomly distributed stabilizer ions.

Specular, crack-free thin films of the refractory conductor zirconium boride have been deposited for possible applications in combined contact/diffusion barrier metallization schemes. Films were deposited by dc triode sputtering, which allowed the independent study of the effects of sputtering pressure, target voltage, and current on the film properties. The mole ratio of boron in the films increased (composition tending to ZrB2) and the resistivity decreased with increasing deposition rates which at a fixed target voltage and sputtering pressure increased almost linearly with target current. Decrease in sputtering pressure, with only a minor change in deposition rate, dramatically decreased resistivity and caused stress in the films to change from tensile to compressive. X-ray photoelectron spectroscopy correlated reduced oxygen content to reduced resistivity. Triode sputtering permitted deposition of films at 2 mTorr with a resistivity of 162 μΩ cm which is the lowest reported value for as-deposited films.

Previous measurements of refractive index vs wavelength for cubic zirconia were extended to include the variation of index with Y(2)O(3) stabilizer concentration. It was found that a three-term Sellmeier formula fits the index data for each concentration to within ~1 x 10(-4) and that the Sellmeier constants have a nonlinear dependence on concentration but do follow the density. Fitting each of the six Sellmeier constants to a threeterm polynomial provides a set of eighteen coefficients sufficient to calculate the index at any wavelength, for any concentration. Conversely, the Y(2)O(3) concentration can be determined from the refractive index with greater accuracy than by chemical analysis.

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Single crystals of NaCl, NaBr, KCl, and KBr containing divalent additions of Ca2+, Sr2+, and Ba2+ were tested mechanically. In the solution‐treated condition, the yield strength, σv, as determined from compression testing in a 〈100〉 direction is essentially dependent on the concentration of the dopant only and is independent of the species of either the dopant or of the host material. All crystals soften on aging, with the exception of the NaCl:Ca2+, NaBr:Ca2+, and NaBr:Sr2+ systems. In addition, correlation was good between σv, and the Knoop hardness number, H, obtained by indentation with the long axis of the indenter aligned in 〈100〉. The equation is of the form σv=C(H–H0), where C≅ 0.21 for all four halide families and H0 is near the hardness value of the pure halides. Furthermore, H0≅5×10−3E111, the Young's modulus in the 〈111〉 direction. Hence σv≅0.21H–10−3E111.

The growth of CdTe by organometallic vapor phase epitaxy has been accomplished at 250 °C, using a new tellurium source, dimethylditelluride. The compound decomposes at a much lower temperature than the corresponding monotelluride, apparently by reacting with a cadmium-containing species to eliminate one tellurium atom. As a result, the temperature necessary for deposition of CdTe has been lowered from the range of 400 °C, thus making completely thermally driven chemical vapor deposition of II-VI compounds possible at much lower temperatures.