Title :
Performance and Stability Improvements of Back-Channel-Etched Amorphous Indium–Gallium–Zinc Thin-Film-Transistors by CF4+O2 Plasma Treatment
Author :
Xiang Liu ; Wang, Lisa Ling ; Hehe Hu ; Xinhong Lu ; Ke Wang ; Gang Wang ; Shengdong Zhang
Author_Institution :
Inst. of Microelectron., Peking Univ., Beijing, China
Abstract :
The performance and stability improvement of back-channel-etched amorphous indium-gallium-zinc oxide thin-film transistors (a-IGZO TFTs) by post CF4+O2 plasma treatment is investigated. It is revealed that the metal residue of the wet-etching of source/drain electrodes degrades TFT performance and aggravates the positive threshold voltage (Vth) shift under positive gate bias stress. It is demonstrated that the CF4+O2 plasma treatment effectively removes the metal residue and remarkably improves device performance and the Vth stability. This improvement is attributed to oxygen vacancy repairing at the back channel interface of the a-IGZO TFT by the O free radicals generated by the O2 plasma.
Keywords :
amorphous semiconductors; carbon compounds; free radicals; gallium compounds; indium compounds; oxygen; sputter etching; thin film transistors; vacancies (crystal); CF4+O2 plasma treatment; CF4-O2; InGaZnO; a-IGZO TFT; back channel etched amorphous indium gallium zinc oxide; back channel interface; free radicals; metal residue; oxygen vacancy repairing; performance improvements; positive gate bias stress; positive threshold voltage; source-drain electrodes; stability improvements; thin film transistors; wet etching; Films; Logic gates; Metals; Performance evaluation; Plasmas; Stress; Thin film transistors; Back-channel-etch (BCE); Plasma treatment; a-IGZO TFTs; back-channel-etch (BCE); plasma treatment; threshold voltage shift;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2015.2456034
