Progress in Developing Highly Efficient p-type TCOs for Transparent Electronics: A Comprehensive Review

Singh, J and Bhardwaj, P and Kumar, R and Verma, V (2024) Progress in Developing Highly Efficient p-type TCOs for Transparent Electronics: A Comprehensive Review. In: Journal of Electronic Materials .

PDF Jou_Ele_Mat_2024.pdf - Published Version Restricted to Registered users only Download (3MB) | Request a copy

Abstract

Transparent conducting oxides (TCOs) represent a remarkable class of materials with excellent electrical conductivity and high optical transparency. This unique combination of properties makes TCOs highly desirable for various applications, particularly in optoelectronic devices such as transparent electrodes for displays, solar cells, and touchscreens. However, developing high-performance TCOs, especially p-type materials, has been a significant challenge. Achieving high electrical conductivity and optical transparency is difficult in conventional materials, as materials with a wide optical bandgap (� 3.1 eV) are transparent in the visible region but lack electrical conductivity, while conductive metals are opaque. Hence, the only way to induce both properties in a single material is to create non-stoichiometry and/or defects. By introducing shallow defects near the conduction band for n-type materials and the valence band for p-type materials, it is possible to enhance the conductivity of the material at room temperature. Developing efficient p-type TCOs presents significant challenges due to the intrinsic localized nature of the valence band, primarily derived from oxygen 2p orbitals. This localization leads to difficulties in achieving shallow acceptor levels, which are crucial for high hole mobility. As a result, the effective mass of holes in these materials tends to be high, limiting their electrical conductivity. Commercially available TCOs are predominantly n-type, such as Sn:In2O3, Al:ZnO, and F:SnO2, while the development of efficient p-type TCOs has lagged. In this review, we discuss the origin of p-type conductivity in TCOs and the difficulties encountered in developing efficient p-type materials. We also demonstrate the fundamental material physics of p-type TCOs, including electronic structure, doping, defect properties, and optical properties. A range of deposition techniques have been adopted to prepare TCO films, and this review provides a detailed discussion of these techniques and their relative deposition parameters. Overall, we present an up-to-date and comprehensive review of different p-type transparent conducting oxide thin films, providing insights into ongoing research and potential future directions in this field. © The Minerals, Metals & Materials Society 2024.

Item Type:	Journal Article
Publication:	Journal of Electronic Materials
Publisher:	Springer
Additional Information:	The copyright for this article belongs to the publishers.
Keywords:	Conductive films; Enameling; Epitaxial growth; Grain boundaries; Hard facing; Layered semiconductors; Light sensitive materials; Luminescence of gases; Luminescence of liquids and solutions; Luminescence of solids; Nanocrystals; Photoelectric microscopes; Semiconductor doping; Spectrophotometry; Transparent electrodes, Electrical conductivity; Optical transparency; Optoelectronics devices; Oxide materials; P-type; Property; Thin-films; Transparent conducting oxide; Transparent electrode; Transparent electronics, Transparent conducting oxides
Department/Centre:	Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering
Date Deposited:	09 Oct 2024 10:17
Last Modified:	09 Oct 2024 10:17
URI:	http://eprints.iisc.ac.in/id/eprint/86344

Actions (login required)

View Item