TY - JOUR
T1 - Double Gated a-InGaZnO TFT Properties Based on Quantitative Defect Analysis and Computational Modeling
AU - Hong, Hyunmin
AU - Yi, Dong Joon
AU - Moon, Yeon Keon
AU - Son, Kyoung Seok
AU - Lim, Jun Hyung
AU - Jeong, Kwang Sik
AU - Chung, Kwun Bum
N1 - Publisher Copyright:
© 1963-2012 IEEE.
PY - 2024/2/1
Y1 - 2024/2/1
N2 - The device characteristics of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) were investigated using both single-gate (SG) and double-gate (DG) structures. The DG a-IGZO TFT demonstrated improved subthreshold swing (SS) and mobility compared to the SG structure. Moreover, in both positive and negative bias stresses (NBSs), the threshold voltage variation in the DG structure was significantly reduced. Quantitative analysis of activation energy and defect density indicated an increase in shallow-level defects and a decrease in deep-level defects within the DG structure. Additionally, based on quantitative defect measurements, the density of state (DOS) in a-IGZO was adjusted according to the structure, and the device properties and electric field distribution were simulated through TCAD. In the DG structure, the electric field was concentrated at both gates, resulting in an increase in bulk electric field intensity. Due to the increase in electric field, the average electron density within the channel in the DG structure increased by a factor of seven compared to the SG structure. This increase in electron density contributed to the enhancement of SS, mobility, and drive current. Additionally, there was a reduction in electron drift in the vertical direction within the channel, leading to an improvement in the stability of the device.
AB - The device characteristics of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) were investigated using both single-gate (SG) and double-gate (DG) structures. The DG a-IGZO TFT demonstrated improved subthreshold swing (SS) and mobility compared to the SG structure. Moreover, in both positive and negative bias stresses (NBSs), the threshold voltage variation in the DG structure was significantly reduced. Quantitative analysis of activation energy and defect density indicated an increase in shallow-level defects and a decrease in deep-level defects within the DG structure. Additionally, based on quantitative defect measurements, the density of state (DOS) in a-IGZO was adjusted according to the structure, and the device properties and electric field distribution were simulated through TCAD. In the DG structure, the electric field was concentrated at both gates, resulting in an increase in bulk electric field intensity. Due to the increase in electric field, the average electron density within the channel in the DG structure increased by a factor of seven compared to the SG structure. This increase in electron density contributed to the enhancement of SS, mobility, and drive current. Additionally, there was a reduction in electron drift in the vertical direction within the channel, leading to an improvement in the stability of the device.
KW - Computational modeling
KW - defect analysis
KW - double gate (DG) thin-film transistor (TFT)
KW - quantitative measurement
UR - http://www.scopus.com/inward/record.url?scp=85181572344&partnerID=8YFLogxK
U2 - 10.1109/TED.2023.3347503
DO - 10.1109/TED.2023.3347503
M3 - Article
AN - SCOPUS:85181572344
SN - 0018-9383
VL - 71
SP - 1097
EP - 1101
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
IS - 2
ER -