Room Temperature Sputtered Aluminum-Doped ZnO Thin Film Transparent Electrode for Application in Solar Cells and for Low-Band-Gap Optoelectronic Devices

Abstract

Aluminum-doped zinc oxide (AZO) is a popular, low-cost, nontoxic material that finds application as a transparent conducting electrode in photonic, sensing, and photovoltaic devices. We report the AZO thin films with a high figure of merit on large-area glass substrates by direct current magnetron sputtering without any intentional substrate heating. Furthermore, a simple thermal post-treatment to improve the transmittance of AZO thin film in the infrared region for its application in low-band-gap devices is presented. High optoelectronic properties are obtained by optimizing oxygen content during the sputtering process. The structural, morphological, optoelectrical, and photoluminescence characterization of cold sputtered AZO films is investigated for its latent applications. AZO thin films with an electrical sheet resistance of 8.8 Ω/□ and a visible light transmittance of 78.5% with thickness uniformity above 95% are achieved on 300 mm × 300 mm glass substrate. The AZO film with optimized process conditions is employed as a transparent electrode to fabricate a copper–indium–gallium–selenide-based thin film solar cell, demonstrating 11.8% power conversion efficiency. The AZO film with optimized sputter conditions was post-treated in ambient conditions with an Al blanket to suppress the resistivity by proper organization of the defects due to Al 3+ consumption and point defects, resulting in improved transparency (85%) in the infrared region with a sheet resistance of 40 Ω/□. This has great potential for developing scalable and low-cost AZO thin films for transparent electrodes in a wide range of the spectrum.

Influence of the AZO Electrode on ZnO Nanowire Growth by PLI-MOCVD and Related Piezoelectric Performance: Implications for Mechanical Energy Transducers

“…21 Among them, AZO is a highly suitable alternative to ITO, as it is composed of abundant elements and considered as a non-toxic material with high electrical conductivity and optical transmittance comparable to ITO. 14,22,23 Using ZnO NWs in combination with AZO electrodes would allow for the fabrication of a transparent piezoelectric device using only non-critical materials. This approach avoids using the materials that may be scarce or toxic or have significant supply risks, thus ensuring the sustainability of the device.…”

“…Indium tin oxide (ITO) is usually selected for the transparent electrode, thanks to its low electrical resistivity (∼10 –4 Ω cm) and high visible light transmittance (>85%). , However, the scarcity and toxicity of indium-based compounds give rise to some concerns related to its supply risk and its cost. − Other materials that can be used for transparent electrodes are, for instance, silver NWs, graphene, fluorine-doped ZnO, fluorine-doped tin oxide, or aluminum-doped ZnO (AZO) . Among them, AZO is a highly suitable alternative to ITO, as it is composed of abundant elements and considered as a non-toxic material with high electrical conductivity and optical transmittance comparable to ITO. ,, Using ZnO NWs in combination with AZO electrodes would allow for the fabrication of a transparent piezoelectric device using only non-critical materials. This approach avoids using the materials that may be scarce or toxic or have significant supply risks, thus ensuring the sustainability of the device.…”

Application of ZnO-NRs@Ni-foam substrate for electrochemical fingerprint of arsenic detection in water

“…Besides these nanomaterials various nanocomposites have been also reported for arsenic detection such as Au-Pt NPs/PANI, boron-doped diamond (BBD), and Au-Ppy NWs. 14,29,37 Zinc oxide (ZnO) is a II-IV semiconductor compound with a direct band gap of ∼3.37 eV and maximum exciton binding energy of ∼60 meV at ambient temperature and has been extensively reported in various elds such as photoelectrical applications, [38][39][40][41] photocatalytic applications, 42,43 antibacterial activity towards pathogenic bacteria for medical application, 44,45 transparent electrode for solar cell, low band gap in optoelectronic devices [46][47][48] etc. Besides its physicochemical characteristics, ZnO reveals environmental advantages like non-toxicity, easy disposal of materials, recyclability, and corrosion resistance.…”

Stabilization of Perovskite Solar Cells: Recent Developments and Future Perspectives

“…The use of lignin‐based QSS electrolytes enhanced the long‐term stability of DSSC in UV–vis light, exploiting the potential of lignin for developing sustainable PV systems. Other emerging concepts are transparent electrodes used in solar cells, [ 8 ] photoelectrochromic devices used for highly stable smart windows, [ 9 ] and textile DSSC for wearable electronics, [ 10 ] among others which require much consideration in future research to fully explore these systems.…”