Improved Electrical Performance of SiO₂-Doped Indium Zinc Oxide Thin-Film Transistor

Yooseong Lim; Namgyung Hwang; Jeongsuk Lee; Sehyeong Lee; Moonsuk Yi

doi:10.1166/jnn.2019.16246

Improved Electrical Performance of SiO₂-Doped Indium Zinc Oxide Thin-Film Transistor

J Nanosci Nanotechnol. 2019 Mar 1;19(3):1470-1473. doi: 10.1166/jnn.2019.16246.

Authors

Yooseong Lim¹, Namgyung Hwang¹, Jeongsuk Lee¹, Sehyeong Lee¹, Moonsuk Yi¹

Affiliation

¹ Department of Electronics Engineering, Pusan National University, Busan, 46241, Republic of Korea.

PMID: 30469207
DOI: 10.1166/jnn.2019.16246

Abstract

In this study, we investigated the effect of oxygen content on the stability and the role of silicon in amorphous SiO₂-doped indium-zinc-oxide thin film transistor. The SiO₂-doped IZO (SIZO) thinfilms were deposited at room temperature by radio-frequency magnetron co-sputtering. To optimize stability and electrical performance, we changed the amount of oxygen by changing oxygen gas ratio in reactive sputtering (11%, 12%, and 13%) and used SiO₂ target to deposit SIZO active layer. By adjusting the parameters of SIZO thin-film transistor (TFT) preparation, we found that the best performance was obtained when the oxygen ratio of a-SIZO films was 11%. The optimized a-SIZO TFT exhibited an on/off current ratio (I_on/I_off) of 2.1×10⁷, saturation mobility (μ_sat) of 53.6 cm²/V . s, threshold voltage (V_th) of -7.3 V, and subthreshold swing (S.S.) of 1.7 V/decade. Compared to a-IZO films, the a-SIZO film showed better stability and electrical performance because it had fewer oxygen vacancies and defects.