Silicon Oxidation in Inductively-Coupled N2O Plasma and its Effect on Polycrystalline-Silicon Thin Film Transistors

Inductively-coupled $N_2$O plasma was utilized to grow silicon dioxide at low temperature and applied to fabricate polycrystalline-silicon thin film transistors. At $400^{\circ}C$, the thickness of oxide was limited to 5nm and the oxide contained Si≡N and ≡Si-N-Si≡ bonds. The nitrogen incorporation improved breakdown field to 10MV/cm and reduced the interface charge density to $1.52$\times$10^{11}$ $cm^2$ with negative charge. The $N_2$O plasma gate oxide enhanced the field effect mobility of polycrystalline thin film transistor, compared to $O_2$ plasma gate oxide, due to the reduced interface charge at the $Si/SiO_2$ interface and also due to the reduced trap density at Si grain boundaries by nitrogen passivation.

유도결합 N2O 플라즈마를 이용한 실리콘 산화막의 저온성장과 다결정 실리콘 박막 트랜지스터에의 영향