Electrical screening of ternary NiO-Mn2O3-Co3O4 composition spreads

The compositional optimization of infrared-transparent conducting oxides was performed using high throughput screening of combinatorial libraries. Complete ternary composition spreads of NiO-Mn2O3-Co3O4 alloys were deposited onto conducting Nb-doped SrTiO3 substrates using the pulsed laser deposition technique. Resistance-temperature relations of each composition in the spread were determined using a custom-designed scanning probe. The binary NiCo2O4 oxide showed the lowest electrical resistivity of about 0.1 Ω cm but unacceptably large resistance-temperature dependence (3.5%/°C). Electrically conducting ternary alloys along the line Mn0.45Ni0.63Co1.92O4-Mn0.60Ni0.72Co1.68O4-Mn0.69Ni0.81Co1.50O4 exhibited much lower temperature sensitivity (of about 1.5%/°C) as well as electrical resistance comparable to that of NiCo2O4. From this screening we propose new compounds for the thin-film ITCO sensors.