Title :
Impacts of
and
Plasma Surface Treatments on High-Performance
Author :
Ma, Ming-Wen ; Chao, Tien-Sheng ; Chiang, Tsung-Yu ; Wu, Woei-Cherng ; Lei, Tan-Fu
Author_Institution :
Inst. of Electron., Nat. Chiao Tung Univ., Hsinchu
Abstract :
Low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs) with high- kappa gate dielectrics and plasma surface treatments are demonstrated for the first time. Significant field-effect mobility muFE improvements of ~ 86.0% and 112.5% are observed for LTPS-TFTs with HfO2 gate dielectric after N2 and NH3 plasma surface treatments, respectively. In addition, the N2 and NH3 plasma surface treatments can also reduce surface roughness scattering to enhance the field-effect mobility muFE at high gate bias voltage V G, resulting in 217.0% and 219.6% improvements in driving current, respectively. As a result, high-performance LTPS-TFT with low threshold voltage V TH ~ 0.33 V, excellent subthreshold swing S.S. ~ 0.156 V/decade, and high field-effect mobility muFE ~ 62.02 cm2 V middots would be suitable for the application of system-on-panel.
Keywords :
elemental semiconductors; hafnium compounds; high-k dielectric thin films; plasma materials processing; silicon; surface roughness; surface treatment; thin film transistors; HfO2; N2 plasma; NH3 plasma; Si; TFT; field-effect mobility; gate bias voltage; high-kappa gate dielectric; low-temperature polycrystalline-silicon thin-film transistors; plasma surface treatments; surface roughness scattering; $hbox{NH}_{3}$ plasma; $hbox{N}_{2}$ plasma; $hbox{NH}_{3}$ plasma; $hbox{N}_{2}$ plasma; High-$kappa$; High-$kappa$; low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2008.2004781