A surface-potential-based drain current compact model for a-InGaZnO thin-film transistors in Non-Degenerate conduction regime. (November 2017)

• Record Type: Journal Article
• Authors: Yu, Fei; Ma, Xiaoyu; Deng, Wanling; Liou, Juin J.; Huang, Junkai
• Is Part Of: Solid-state electronics. Volume 137(2017)
• Page Start: 38
• Page End: 43
• Publication Date: 2017-11
• Subjects: Amorphous InGaZnO (a-InGaZnO) -- Compact model -- Surface potential -- Drain current -- Thin film transistors; Semiconductors -- Periodicals; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.sse.2017.07.016
• Languages: English
• ISSNs: 0038-1101

Abstract

Highlights: In this paper, based on the explicit calculation of surface potential, we utilize the charge sheet approach to develop a physics-based compact I-V model for a-InGaZnO TFTs accounting for both tail and deep trap states. In the process of calculating the surface potential, saturation voltage is defined, dominant physical phenomena asymptotic is used, and corresponding explanation about the effect from DOS on surface potential is expound clearly. It can explain the electrical characteristics of a-InGaZnO TFTs and be suitable for computer-aided-design (CAD) implementation. Abstract: A physics-based drain current compact model for amorphous InGaZnO (a-InGaZnO) thin-film transistors (TFTs) is proposed. As a key feature, the surface potential model accounts for both exponential tail and deep trap densities of states, which are essential to describe a-InGaZnO TFT electrical characteristics. The surface potential is solved explicitly without the process of amendment and suitable for circuit simulations. Furthermore, based on the surface potential, an explicit closed-form expression of the drain current is developed. For the cases of the different operational voltages, surface potential and drain current are verified by numerical results and experimental data, respectively. As a result, our model can predict DC characteristics of a-InGaZnO TFTs.