Abstract
We optimized silicon nitride (SiN x) layers, deposited by 13.56 MHz plasma enhanced chemical vapor deposition (PECVD) at 150°C, to provide a high quality gate dielectric layer for the amorphous silicon thin film technology on polyimide foils. The layers were deposited from mixtures of silane, ammonia, and hydrogen. We varied the H 2 flow rate from 55 to 220 sccm and the rf power from 5 to 50 W, while the pressure was kept at 500 mTorr and the ratio of ammonia to silane flow at 10:1. The best film was obtained from the gas composition of SiH 4:NH 3:H 2 = 1:10:44 and the rf power of ∼20 W. This film grows at the rate of 1.5 Å/s, has a refractive index n = 1.80, a dielectric constant ε = 7.46, a dielectric breakdown field >3.4 MV/cm, a Si/N ratio of ∼0.67, and a hydrogen content of ∼2 × 10 22cm -3, and etches in 10:1 buffered HF at a rate of 61 Å/s.
Original language | English |
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Pages (from-to) | 12-16 |
Number of pages | 5 |
Journal | Applied Surface Science |
Volume | 175-176 |
DOIs | |
Publication status | Published - 15 May 2001 |
Event | 10th International Conference on Solid Films and Surfaces - Princeton, New Jersey, United States Duration: 10 Jul 2000 → 13 Jul 2000 |
Keywords
- thin-film electronics
- silicon nitride
- polyimide foil substrates