Title :
The effects of NH3 plasma passivation on polysilicon thin-film transistors
Author :
Fang-Shing Wang ; Meng-Jin Tsai ; Huang-Chung Cheng
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
The NH3 plasma passivation has been performed for the first time on the polycrystalline silicon (poly-Si) thin-film transistors (TFT´s). It is found that the TFT´s after the NH3 plasma passivation achieve better device performances, including the off-current below 0.1 pA/μm and the on/off current ratio higher than 10/sup 8/, and also better hot-carrier reliability as well as thermal stability than the H2-plasma devices. These improvements were attributed to not only the hydrogen passivation of the grain-boundary dangling bonds, but also the nitrogen pile-up at SiO2/poly-Si interface and the strong Si-N bond formation to terminate the dangling bonds at the grain boundaries of the polysilicon films.
Keywords :
dangling bonds; grain boundaries; hot carriers; passivation; semiconductor device reliability; silicon; thin film transistors; N pile-up; NH/sub 3/; Si; device performance; grain-boundary dangling bonds; hot-carrier reliability; off-current; on/off current ratio; plasma passivation; polysilicon thin-film transistors; thermal stability; Grain boundaries; Hot carriers; Hydrogen; Nitrogen; Passivation; Plasma devices; Plasma stability; Silicon; Thermal stability; Thin film transistors;
Journal_Title :
Electron Device Letters, IEEE
