Transparent conductors as solar energy materials: A panoramic review

Solution combustion is an exciting phenomenon, which involves propagation of self-sustained exothermic reactions along an aqueous or sol–gel media. This process allows for the synthesis of a variety of nanoscale materials, including oxides, metals, alloys, and sulfides. This Review focuses on the analysis of new approaches and results in the field of solution combustion synthesis (SCS) obtained during recent years. Thermodynamics and kinetics of reactive solutions used in different chemical routes are considered, and the role of process parameters is discussed, emphasizing the chemical mechanisms that are responsible for rapid self-sustained combustion reactions. The basic principles for controlling the composition, structure, and nanostructure of SCS products, and routes to regulate the size and morphology of the nanoscale materials are also reviewed. Recently developed systems that lead to the formation of novel materials and unique structures (e.g., thin films and two-dimensional crystals) with unusual...

Solution Combustion Synthesis of Nanoscale Materials

Electrical and optical properties of ZnO transparent conducting films by the sol-gel method

Mechanical integrity of transparent conductive oxide films for flexible polymer-based displays

Transparent conducting ZnO:Al, In and Sn thin films deposited by the sol–gel method

Growth of CuInSe2 thin films by high vapour Se treatment of co-sputtered Cu-In alloy in a graphite container

The relation between electrical and structural properties of indium tin oxide (ITO) films prepared by pulsed laser deposition with and without in situ laser irradiation is examined. The residual stresses of the films were estimated from x-ray diffraction patterns measured by grazing-incidence asymmetric Bragg and grazing-incidence x-ray diffraction geometries. For the films prepared without in situ irradiation, the residual stress depended on oxygen pressure (PO2) during deposition and had minimum around PO2 of 1.3 Pa, which coincided with the optimum PO2 for growing the lowest resistivity films. The resistivity was only slightly improved with an increase of substrate temperature (Ts) because a large residual stress was introduced. In contrast, the ITO films prepared with in situ laser irradiation showed very low resistivity (ρ<10−4 Ω cm) which can be attributed to the high crystallinity and low residual stress.

Electrical and structural properties of indium tin oxide films prepared by pulsed laser deposition

Amorphous indium oxide (In2O3) and 10-wt% SnO2 doped In2O3 (ITO) thin films were prepared by pulsed-laser deposition. These films were crystallized upon heating in vacuum at an effective heating rate of 0.00847 °C/s, while the evolution of the structure was observed by in situ X-ray diffraction measurements. Fast crystallization of the films is observed in the temperature ranges 165–210 °C and 185–230 °C for the In2O3 and ITO films, respectively. The crystallization kinetics is described by a reaction equation, with activation energies of 2.31 ± 0.06 eV and 2.41 eV and order of reactions of 0.75 ± 0.07 and 0.75 for the In2O3 and ITO films, respectively. The structures of the films observed here during heating are compared with those obtained upon film growth at different temperatures. The resistivity of the films depends on the evolution of the structure, the oxygen content and the activation of tin dopants in the films. A low resistivity of 5.5 × 10−4 Ω cm was obtained for the In2O3 and ITO films at room temperature, after annealing to 250 °C the resistivity of the ITO film reduces to 1.2 × 10−4 Ω cm.

Crystallization process and electro-optical properties of In2O3 and ITO thin films

Pure indium oxide (In2O3) and SnO2-doped In2O3 (5 and 10 wt %) films were deposited on glass at different substrate temperatures (Ts) ranging from room temperature (RT=25 °C) to 350 °C using pulsed laser deposition. At low Ts (RT to 100 °C), pure In2O3 films yielded the lowest resistivity of (1.8–2.5)×10−4 Ω cm and the resistivity increased sharply with an increase in Ts, and the rise in the resistivity of pure In2O3 films resulted mainly from a decrease in carrier concentration and Hall mobility. For SnO2-doped In2O3 films, the resistivity decreased from 3.5×10−4 to 1.3×10−4 Ω cm with increasing Ts from RT to 350 °C and the reduction in the resistivity is associated with thermal activation of Sn leading to an increase in carrier concentration. Amorphous films were obtained at RT, but from Ts of 100 °C, the films appeared polycrystalline with orientation in the 〈111〉 plane. From atomic force microscopy, minimum surface roughness (Ra)⩽1.3 nm was obtained at RT and Ts>200 °C. Between 100 and 150 °C, Ra was maximum (2.5–4.9 nm). The films also exhibited high optical transmittance (>85%) to visible light.

Influence of substrate temperature on the properties of indium oxide thin films

Indium tin oxide (ITO) thin films were grown on SiO2 glass and silicon (Si) substrates from a 95 wt% In2O3–5 wt% SnO2 sintered ceramic target by pulsed laser deposition (PLD). The films were deposited under different oxygen pressures (Po2) of 5×10-3 to 5×10-2 Torr at room temperature (RT) and 200°C. Po2 was found to have a critical influence on the optical and the electrical properties of the ITO films. Under a Po2 of 1×10-2 Torr, ITO films with resistivity as low as 4.5×10-4 and 1.8×10-4 Ωcm were obtained on glass at RT and 200°C, respectively. Moreover, by increasing the substrate temperature (Ts) to 350°C, the resistivity was further reduced to 1.3×10-4 Ωcm. Optical transmittance in visible light greater than 85% was attained in all the films deposited under Po2 above 5× 10-3 Torr. However, a reduction in the transmittance to less than 80% was observed as Po2 decreased. The films deposited at RT were amorphous, whereas those produced at 200°C were polycrystalline.

https://iopscience.iop.org/article/10.1143/JJAP.38.2710/pdf

F.O. Adurodija

Papers

Growth of CuInSe2 thin films by high vapour Se treatment of co-sputtered Cu-In alloy in a graphite container

Electrical and structural properties of indium tin oxide films prepared by pulsed laser deposition

Crystallization process and electro-optical properties of In2O3 and ITO thin films

Influence of substrate temperature on the properties of indium oxide thin films

Pulsed Laser Deposition of Low-Resistivity Indium Tin Oxide Thin Films at Low Substrate Temperature