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BaCuQF (Q=S,Se) materials, candidate transparent p-type conductors, were prepared by solid-state reaction, and their bulk electrical and optical properties were evaluated. The room-temperature Seebeck coefficient and electrical conductivity of undoped BaCuQF pellets were +56 μV/K and 0.088 S/cm, respectively, for the sulfide fluoride, and +32 μV/K and 0.061 S/cm, respectively, for the selenide fluoride. The conductivity was greatly enhanced by the substitution of several percent of K for Ba; the highest conductivities were 82 S/cm for Ba0.9K0.1CuSF and 43 S/cm for Ba0.9K0.1SeF. The band gaps for Q=S and Q=Se were measured to be 3.2 and 3.0 eV, respectively. Undoped BaCuSF exhibits strong red luminescence near 630 nm under ultraviolet excitation.

Radioactive 111In has been incorporated into oriented thin films of YBa2Cu3O7−δ during a thermal coevaporation process. The hyperfine technique of perturbed γγ‐angular correlation spectroscopy shows that 60% of the indium substitutes at a single site in the superconductor. We obtain spectra with reasonable statistics from 2 mCi of starting material, about 1% of which is incorporated into the film. Other methods of incorporating indium into films and bulk YBa2Cu3O7−δ have often resulted in a significant amount of indium being incorporated into impurity phases.

SnS is a potential earth-abundant photovoltaic (PV) material. Employing both theory and experiment to assess the PV relevant properties of SnS, we clarify on whether SnS has an indirect or direct band gap and what is the minority carrier effective mass as a function of the film orientation. SnS has a 1.07 eV indirect band gap with an effective absorption onset located 0.4 eV higher. The effective mass of minority carrier ranges from 0.5 m0 perpendicular to the van der Waals layers to 0.2 m0 into the van der Waals layers. The positive characteristics of SnS feature a desirable p-type carrier concentration due to the easy formation of acceptor-like intrinsic Sn vacancy defects. Potentially detrimental deep levels due to SnS antisite or S vacancy defects can be suppressed by suitable adjustment of the growth condition towards S-rich.

Transparent films of CuScO2+x have been prepared which show p-type electrical conductivity. The temperature dependence of the conductivity indicates semiconducting behavior with an apparent room temperature activation energy of 0.11 eV. The highest room temperature conductivity observed was 30 S cm−1. Films 110 nm thick show 40% transparency in most of the visible spectrum and become much more transparent in the infrared spectrum. The p-type behavior was confirmed by the Seebeck effect.

High electron mobility thin films of In2−xWxO3+y(0⩽x⩽0.075) were prepared on amorphous SiO2 and single-crystal yttria-stablized zirconia (001) substrates by pulsed laser deposition. Mobilities ranged between 66 and 112cm2∕Vs depending on the substrate type and deposition conditions, and the highest mobility was observed at a W-dopant concentration of x∼0.03. A small band gap shift was detected from films with increasing electron carrier density; the electron effective mass calculated from Burstein-Moss theory was 0.3me. In2−xWxO3+y films have high visible transmittance of ∼80%.

We used simple thermal coevaporation of yttrium, barium, and copper in an oxygen atmosphere to produce thin films of the 90 K superconductor, YBa2Cu3O7−δ, on silicon, magnesium oxide, and strontium titanate. The films were deposited on 650 °C substrates and were superconducting when removed from the evaporator. A short post‐anneal at 480 °C produced films on bare Si with transition temperatures (R=0) of 85 K. Films as thin as 0.13 μm, superconducting at 91 K (on MgO) and 89 K (on SrTiO3), were obtained with no post‐anneal.