On the Origin of Improved Charge Transport in Double-Gate In-Ga-Zn-O Thin-Film Transistors: A Low-Frequency Noise Perspective
- 저자
- Yong Xu, Chuan Liu, Paul Seyram K. Amegadez, Gi-Seong Ryu, Huaixin Wei, Francis Balestra, Gerard Ghibaudo, and Yong-Young Noh*
- 저널명
- IEEE Electron Device Letters
- 년도
- 2015
- Link
- http://dx.doi.org/10.1109/LED.2015.2467164 154회 연결
[Abstract]
Low-frequency noise (LFN) in double-gate (DG) In-Ga-Zn-O (IGZO) thin-film transistors (TFTs) is studied to investigate the origin of performance improvement. We found that thinning down the IGZO film enhances such improvements. With 7-nm IGZO, the mobility is raised by a factor of 3.77, and the subthreshold slope is reduced to 0.17 V/decade from single-gate to DG mode. Device simulations show that bulk transport inside IGZO film emerges as the two gates field effects get coupled. The LFN results reveal a transport transition from surface to bulk and disclose the superior bulk transport that experiences slight phonon scattering with a small Hooge parameter α H = 4.44 × 10 -3 whereas the surface transport undergoes serious charge trapping with surface trap densities about 2 × 10 11 eV -1 cm -2 .