Transparent conductors as solar energy materials: A panoramic review

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

Discovery-based design of transparent conducting oxide films

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

Electrical properties of crystalline ITO films prepared at room temperature by pulsed laser deposition on plastic substrates

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

Hideki Yoshioka

Papers

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

Electrical properties of crystalline ITO films prepared at room temperature by pulsed laser deposition on plastic substrates

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

Highly conducting indium tin oxide (ITO) thin films deposited by pulsed laser ablation