Doreen D. Edwards

A new transparent conducting oxide in the Ga2O3–In2O3–SnO2 system

A new transparent conducting oxide (TCO), which can be expressed as Ga3−xIn5+xSn2O16; 0.2⩽x⩽1.6, has been identified. The equilibrium phase relationships of this new material with respect to three other TCOs in Ga2O3–In2O3–SnO2 are reported. The optical properties of this phase are slightly superior to Sn-doped indium oxide (ITO) and depend on composition. A room-temperature conductivity of 375 Ωu2009cm−1 was obtained for H2-reduced Ga2.4In5.6Sn2O16. This value is an order of magnitude lower than commercial ITO films, but comparable to values reported for bulk, polycrystalline Sn-doped In2O3.

Experimental limitations in impedance spectroscopy: Part V. Apparatus contributions and corrections

Overlooked apparatus (cabling, leads, sample holder) contributions to experimental impedance spectra can be significant, especially at high frequencies, and can obscure the true sample response. Instrumental limitations are discussed and high-frequency artifacts arising from apparatus contributions are investigated as they pertain to accurate impedance measurements of materials systems. Remediation strategies are presented, including geometrical adjustments, lead shielding, and null-correction procedures.

Phase equilibria in the Ga2O3-In2O3 system

Subsolidus phase relationships in the Ga{sub 2}O{sub 3}-In{sub 2}O{sub 3} system were studies by X-ray diffraction and electron probe microanalysis (EPMA) for the temperature range of 800--1,400 C. The solubility limit of In{sub 2}O{sub 3} in the {beta}-gallia structure decreases with increasing temperature from 44.1 {+-} 0.5 mol% at 1,000 C to 41.4 {+-} 0.5 mol% at 1,400 C. The solubility limit of Ga{sub 2}O{sub 3} in cubic In{sub 2}O{sub 3} increases with temperature from 4.8 {+-} 0.5 mol% at 1,000 C to 10.0 {+-} 0.5 mol% at 1,400 C. The previously reported transparent conducting oxide phase in the Ga-In-O system cannot be GaInO{sub 3}, which is not stable, but is likely the In-doped {beta}-Ga{sub 2}O{sub 3} solid solution.

Experimental limitations in impedance spectroscopy of materials systems

Using resistor-capacitor networks, sources of experimental artifacts in impedance spectroscopy were investigated, such sources include machine limitations, rig/cabling contributions at high frequencies, and artifacts due to high impedance reference electrodes and their geometrical placement. In the instance of electrode placement, computer simulations with a pixel-based model were in agreement with the experimental observations. Remedies for these artifacts such as rig shielding/grounding, geometrical adjustments, and null corrections are also discussed.

Systematic study of transparent conductors in the (zinc, gallium)-indium-tin oxide systems

Bulk samples of transparent conducting oxides (TCOs) in the Zn-In-Sn and Ga-In-Sn oxide systems were prepared by solid state processing. Phase relations and physical properties were determined and the results compared to similar measurements on thin film materials.

Phase Equilibria and Properties of Transparent Conductors in the Indium-Tin-Zinc Oxide System

Solid state bulk processing techniques were used to synthesize various transparent conducting oxides (TCOs) with In, Zn, and Sn cations. Optical and electronic properties of resultant phase-pure TCOs were compared to each other and to bulk samples of Sn-doped In2O3 (ITO). Redn. and heat treatment showed significant effects on optical and electronic performance, indicating optimization of processing conditions will be required for industrial applications. Comparison of optical and electronic properties in the series of compds.: ZnkIn2O3+k k = 3,4,5,7,11 revealed trends correlated with the materials internal structure. These layered compds. showed improvement of optical properties at higher Zn contents and improvement in cond. at higher In contents. The trends suggest these materials may be useful for applications where tradeoffs between cond. and transparency are acceptable. Proceedings of the Materials Research Society, Spring 1997, symposium G: Flat Panel Display Materials and Large Area Processes, 1993, 471, 93 Abstract from SciFinderfrom SciFinder

Phase Equilibria in the Ga2O3In2O3 System

Subsolidus phase relationships in the Ga{sub 2}O{sub 3}-In{sub 2}O{sub 3} system were studies by X-ray diffraction and electron probe microanalysis (EPMA) for the temperature range of 800--1,400 C. The solubility limit of In{sub 2}O{sub 3} in the {beta}-gallia structure decreases with increasing temperature from 44.1 {+-} 0.5 mol% at 1,000 C to 41.4 {+-} 0.5 mol% at 1,400 C. The solubility limit of Ga{sub 2}O{sub 3} in cubic In{sub 2}O{sub 3} increases with temperature from 4.8 {+-} 0.5 mol% at 1,000 C to 10.0 {+-} 0.5 mol% at 1,400 C. The previously reported transparent conducting oxide phase in the Ga-In-O system cannot be GaInO{sub 3}, which is not stable, but is likely the In-doped {beta}-Ga{sub 2}O{sub 3} solid solution.

Phase equilibria in the Ga{sub 2}O{sub 3}-In{sub 2}O{sub 3} system

Subsolidus phase relationships in the Ga{sub 2}O{sub 3}-In{sub 2}O{sub 3} system were studies by X-ray diffraction and electron probe microanalysis (EPMA) for the temperature range of 800--1,400 C. The solubility limit of In{sub 2}O{sub 3} in the {beta}-gallia structure decreases with increasing temperature from 44.1 {+-} 0.5 mol% at 1,000 C to 41.4 {+-} 0.5 mol% at 1,400 C. The solubility limit of Ga{sub 2}O{sub 3} in cubic In{sub 2}O{sub 3} increases with temperature from 4.8 {+-} 0.5 mol% at 1,000 C to 10.0 {+-} 0.5 mol% at 1,400 C. The previously reported transparent conducting oxide phase in the Ga-In-O system cannot be GaInO{sub 3}, which is not stable, but is likely the In-doped {beta}-Ga{sub 2}O{sub 3} solid solution.