Amorphous InGaZnO thin film transistors with SiO2/HfO2 double-layer gate dielectric fabricated at low temperature

作者：Kim Ji Hong; Kim Jae Won; Roh Ji Hyung; Lee Kyung Ju; Do Kang Min; Shin Ju Hong; Koo Sang Mo; Moon Byung Moo^*

来源：Materials Research Bulletin, 2012, 47(10): 2923-2926.

DOI：10.1016/j.materresbull.2012.04.134

• Amorphous materials
• Laser deposition
• Dielectric properties
• Electrical properties

Amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) with double-layer gate dielectric were fabricated at low temperature and characterized. A stacked 150 nm-thick SiO2/50 nm-thick HfO2 dielectric layer was employed to improve the capacitance and leakage characteristics of the gate oxide. The SiO2/HfO2 showed a higher capacitance of 35 nF/cm(2) and a lower leakage current density of 4.6 nA/cm(2) than 200 nm-thick SiO2. The obtained saturation mobility (mu(sat)), threshold voltage (V-th), and subthreshold swing (S) of the fabricated TFTs were 18.8 cm(2) V-1 s(-1), 0.88 V. and 0.48 V/decade, respectively. Furthermore, it was found that oxygen pressure during the IGZO channel layer deposition had a great influence on the performance of the TFTs.

• 出版日期2012-10