초록

우리는 Mg0.1Zn0.9O/ZnO 활성층 구조의 박막트랜지스터의 특성을 조사하였다. ZnO와 Mg0.1Zn0.9O 박막은 RF co-sputter 장비를 이용하여 열 산화된 실리콘 기판위에 증착이 되었다. 활성층의 총 두께는 50 nm이다. 우선, ZnO 박막을 5 ~ 30 nm까지 두께를 조절하여 증착을 하였다. 이어서 Mg0.1Zn0.9O 박막을 45 ~ 20 nm까지 변화시켜 증착하였다. 이중 활성층 TFT 소자는 단일 활성층 TFT 소자보다 향상된 특성을 보였다. ZnO 두께가 10 nm일 때 Mg0.1Zn0.9O/ZnO TFT 소자의 전계이동도는 7.40 cm2V-1s-1이고 subthreshold slope은 0.24 V/decade를 가졌다.

Abstract

We report the characteristics of thin-film transistor (TFT) to make the bi-channel structure with stacked Mg0.1ZnO0.9O (Mg= 10 at.%) and ZnO. The ZnO and Mg0.1Zn0.9O thin films were deposited by radio frequency (RF) co-sputter system onto the thermally oxidized silicon substrate. A total thickness of active layer was 50 nm. Firstly, the ZnO thin films were deposited to control the thickness from 5 nmto 30 nm. Sequentially, the Mg0.1Zn0.9O thin films were deposited to change from 45 nm to 20 nm. Thebi-layer TFT shows more improved properties than the single layer TFT. The field effect mobility and sub threshold slope for Mg0.1Zn0.9O/ZnO-TFT are 7.40 cm2V-1s-1 and 0.24 V/decade at the ZnO thickness of 10 nm, respectively.

• Keywords: ZnO, MgZnO, Heterostructure, I-V