1 10 100 1000 10000
∆ G
m/ G
m(100%)
FIG. 4.13 Transconductance degradation of S1 and M10 TFT as a function of the stress time with different frequencies (DC, f = 1K Hz, and f = 1M Hz).
Stress time (sec)
1 10 100 1000 10000
∆ Vth
FIG. 4.14. Teshold voltage of S1 and M10 TFT as a function of the stress time with different frequencies.
Stress time (sec)
1 10 100 1000 10000
∆ SS
FIG. 4.15. Subthreshold swing variation of S1 and M10 TFT as a function of the stress time with different frequencies.
Stress time (sec)
1 10 100 1000 10000
∆ I
on/ I
on(%)
stress time with different frequencies.Stress time (sec)
1 10 100 1000 10000
Ion / Ioff
FIG. 4-17. ON/OFF ratio of S1 and M10 TFT as a function of the stress time with different frequencies.
FIG. 4-18. Gm degradation of S1 and M10 TFT as a function of the stress time with different rising time (Tr) and falling time (Tf) under the frequency of 1 KHz.
Fig. 4-19. Dependence of emission intensity on (a) pulse rise time and (b) pulse fall time. Emission intensity is independent of the pulse rise time. However, we have found that it strongly depends on the fall time.
Stress time (sec)
1 10 100 1000
∆ Vt h
0.0 0.5
M10 tr=tf=100ns S1 tr=tf=100ns M10 tr=1us tf=100ns S1 tr=1us tf=100ns M10 tr=100ns tf=1us S1 tr=100ns tf=1us
FIG. 4-20. Vth variation of S1 and M10 TFT as a function of the stress time with different rising time (Tr) and falling time (Tf) under the frequency of 1 KHz.
Stress time (sec)
FIG. 4-21. ON current (Ion) degradation of S1 and M10 TFT as a function of the stress time with different rising time (Tr) and falling time (Tf) under the frequency.
Stress time (sec)
FIG. 4-22. Gm degradation of S1 and M10 TFT as a function of the stress time with different subtract temperature with 250C, and 750C under the same frequency of 1 KHz.
Stress time (sec)
FIG. 4-23. Vth variation of S1 and M10 TFT as a function of the stress time with 250C, and 750C under the same frequency of 1 KHz.
FIG. 4-24. ON current (Ion) degradation of S1 and M10 TFT as a function of the stress time with 250C, and 750C under the same frequency of 1 KHz.
Chapter 5 Conclusion
For the first part, we have proposed and successfully demonstrated the novel poly-Si TFT device with FSG film as the spacers to enhance the electrical characteristics due to fluorine passivation effect. The poly-Si TFT with FSG spacers exhibits superior endurance against hot carrier effect, leading to improved electrical reliability and suppressed kink effect than the TFT with TEOS SiO2 spacer. In addition, the manufacture processes are compatible with the conventional TFT process. This indicates our proposed poly-Si TFT with FSG spacers is a promising technology for application in the TFT-LCDs.
In the second part, the performance and AC & DC reliability of multiple nanowire poly-Si TFTs are investigated. The experiment results reveal that the multiple nanowire poly-Si TFTs has higher performance than single-channel TFT, including a high ON/OFF current ratio, a low subthreshold slope, an absence of DIBL and favorable output characteristics. In static and dynamic hot-carrier stress experiments, the multiple nanowire poly-Si TFTs reduces the degradation of Vth, SS, Ion, On/OFF ratio and DIBL,
for all kind of frequency, rising time, falling time and temperature, compared to single-channel TFT. These high reliability results of multiple nanowire poly-Si TFTs can be explained by its robust tri-gate control and its superior channel NH3 passivation on the poly-Si grain boundary. The fabrication of this novel multiple nano-wire channel structure TFTs is easy and involves no additional processes. Such TFTs are thus highly promising for use in future high-performance poly-Si TFT applications.
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簡歷
姓名：馮立偉 性別：男
出生日期：中華民國六十九年十月八日 籍貫：高雄市
地址：高雄縣鳳山市福德街
143 巷 36 號 7 樓
學歷：國立中山大學物理系