Speaker
Description
Research on amorphous oxide semiconductors (AOS) has developed rapidly over the last two decades driven by the search for thin-film transistor channel materials suitable for the backplanes of high-definition active matrix displays with organic light-emitting diodes (AMOLED) and for performance optimization of low-cost sensing networks (e.g. RFID-chips) that can be incorporated into smart clothing. AOS materials show remarkable electrical transport properties despite their disordered structure. In contrast to polycrystalline materials the charge carrier transport in AOS is not limited by grain boundary scattering and occurs via delocalized s-orbital states above the mobility edge.[1] The amorphous multi-cation compound zinc tin oxide (a-ZTO) and the amorphous multi-anion compound zinc oxynitride (a-ZnON) with electron Hall mobilities of $13\, \text{cm}^2\text{V}^{-1}\text{s}^{-1}$ [2] or up to $100\, \text{cm}^2\text{V}^{-1}\text{s}^{-1}$ [3,4] have been proven to be possible indium-free alternatives to amorphous indium gallium zinc oxide (a-IGZO) for pixel drivers in active matix displays.
In this talk results on a-ZnON with magnesium cation substitution and its effect on the optical and electrical properties are presented. Furthermore, a short insight into the percolative charge carrier transport mechanism and an overview covering the latest device applications based on a-ZnON, a-ZnMgON and a-ZTO as pn-diodes and metal-semiconductor field-effect transistors (MESFETs)[5] is given.
[1] H. Hosono et al., J. Non-Cryst. Solids 352, 851 (2006)
[2] P. Schlupp et al., MRS Proceedings 1633, 101-104 (2014)
[3] A. Reinhardt et al., Phys. Status Solidi A 213 (7), 1767 (2016)
[4] H. Kim et al., Sci. Rep. 3, 1459 (2013) \newline
[5] A. Reinhardt et al., Adv. Electron. Mater 6, 1901066 (2020)
