Title :
Effect of SiNx Gate Dielectric Deposition Power and Temperature on a-Si:H TFT Stability
Author :
Kattamis, Alex Z. ; Cherenack, Kunigunde H. ; Hekmatshoar, Bahman ; Cheng, I-Chun ; Gleskova, Helena ; Sturm, James C. ; Wagner, Sigurd
Author_Institution :
Princeton Univ., Princeton
fDate :
7/1/2007 12:00:00 AM
Abstract :
The stability of thin-film transistors (TFTs) of hydrogenated amorphous-silicon (a-Si:H) against gate-bias stress is improved by raising the deposition power and temperature of the silicon nitride gate dielectric. We studied the effects of power density between 22 and 110 mW/cm2 and temperature between 150degC and 300degC . The time needed to shift the threshold voltage by 2 V varies by a factor of 12 between low power and low temperature, and high power and high temperature. These results highlight the importance of fabricating a-Si:H TFTs on flexible plastic with the SiNx gate dielectric deposited at the highest possible power and temperature.
Keywords :
amorphous semiconductors; chemical vapour deposition; dielectric devices; flexible electronics; silicon compounds; thin film transistors; SiN; TFT stability; deposition power; deposition temperature; gate dielectric; hydrogenated amorphous-silicon; silicon nitride; temperature 150 C to 300 C; thin-film transistors stability; Capacitive sensors; Dielectric substrates; Plasma stability; Plasma temperature; Plastics; Radio frequency; Silicon compounds; Stress; Thin film transistors; Threshold voltage; Amorphous-silicon (a-Si:H); electrical stability; flexible substrate; plasma power; silicon nitride gate dielectric; thin-film transistor (TFT);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2007.900078
