Physically-based simulation of zinc oxide thin-film transistors: Contact resistance contribution on density of states. (June 2016)

• Record Type: Journal Article
• Authors: Dominguez, Miguel A.; Alcantara, Salvador; Soto, Susana
• Is Part Of: Solid-state electronics. Volume 120(2016)
• Page Start: 41
• Page End: 46
• Publication Date: 2016-06
• Subjects: ZnO -- Simulation -- Thin film transistors -- Density of states; Semiconductors -- Periodicals; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.sse.2016.03.006
• Languages: English
• ISSNs: 0038-1101

Abstract

Highlights: DOS is modeled to reproduce the experimental electrical characteristics of ZnO TFTs. Contact resistance was extracted from the ZnO TFTs and included into the simulation. Higher density of acceptor-like states is necessary to compensate the Rc contribution. Rc and acceptor-like states may affect the electrical characteristics in similar ways. Abstract: In this work, using a physically-based simulator, the density of states DOS is modeled to reproduce the experimental electrical characteristics of ZnO TFTs fabricated by Ultrasonic Spray Pyrolysis at 200 °C. The contact resistance was experimentally extracted from the ZnO TFTs and included into the simulation, in order to separate the metal–semiconductor interface contribution from the DOS. A comparison between the modeled DOS considering the contact resistance and disregarding it is also presented. It is proposed to consider the acceptor-like states and the tail-donor states, where the deep-acceptor states have approximately an exponential form and the distribution of tail-acceptor states are sharper than the distribution of tail-donor states. The simulated electrical characteristics reproduce very well the experimental data at different channel lengths. The use of physically-based simulation can be useful to model the DOS of Oxide semiconductor films in TFTs by reproducing the experimental data.