(INVITED) Solution Processed High-k Dielectrics for Thin Film Transistors Employing Metal Oxide-based Semiconducting Channels

Adamopoulos, George (2016) (INVITED) Solution Processed High-k Dielectrics for Thin Film Transistors Employing Metal Oxide-based Semiconducting Channels. In: BIT's 5th Annual World Coongress of Advanced Materials 2016, 2016-06-06 - 2016-06-08, Chongqing.

Abstract

Whilst progress on solution-processed oxide semiconductors has been rapidly advancing, research efforts towards the development of dielectric materials has been relatively slow, with most of the reported work performed using conventional dielectrics based on SiO2 that usually results in high voltage transistor operation and hence increased power consumption. This ever increasing demand for high performance thin film transistors based on metal oxide channels has given a boost to the development of alternatives to SiO2 gate dielectrics with desirable characteristics in terms of thermal stability, band offsets and interface quality. To that end and among the different approaches, the use of high-k dielectrics is arguably the most attractive option, since it can enable low leakage currents, through the use of physically thicker films, as well as low-voltage operation. This work reports on the structure and properties of a wide range of solution-processed binary and ternary gate dielectrics and their implementation in TFTs employing n and p type metal oxide-based semiconducting channels. It mainly focuses on the band offsets, dielectric and optical as well as the dielectric/semiconductor interface properties and their effects on the device operation. References: 1. M. Esro, R. Mazzocco, G. Vourlias, O. Kolosov, A. Krier, W. I. Milne and G. Adamopoulos, Solution processed lanthanum aluminate gate dielectrics for use in metal oxide-based thin film transistors, Appl. Phys. Lett. 106, 203507, 2015 2. M. Esro, S. Georgakopoulos, H. Lu, G. Vourlias, A. Krier, W. I. Milne, W. P. Gillin and G. Adamopoulos, Solution processed SnO2:Sb transparent conductive oxide as an alternative to indium tin oxide for applications in organic light emitting diodes, J. Mater. Chem. C, 4, 3563, 2016. 3. D. Afouxenidis, R. Mazzocco, G. Vourlias, P. J. Livesley, A. Krier, W. I. Milne, O. Kolosov and G. Adamopoulos, ZnO-based thin film transistors employing aluminum titanate gate dielectrics deposited by spray pyrolysis at ambient air, ACS Appl. Mater. Inter., 7, 7334, 2015. 4. M. Esro, G. Vourlias, C. Somerton, W. I. Milne and George Adamopoulos, High mobility ZnO thin film transistors based on solution-processed hafnium oxide gate dielectrics, Adv. Funct. Mater., 25, 134, 2015.