傳統(0001)面的低壓SiC MOSFETs元件因為SiC/SiO2介面的高Dit，通道遷移率受到了限制，為了改善這個問題，本實驗提出了利用(112̅0)面側壁作為部分通道的tri-gate結構，並且分別使用NO、N2O進行氧化後退火降低Dit並比較他們帶來的影響。
本論文使用N型MOS capacitors、平面型MOSFETs、tri-gate MOSFETs來評估元件的特性以及氧化後退火的比較。跟N2O製程比起來NO製程(0001)面在距離傳導帶0.1 eV處的Dit值下降了約40 %，而且sub-threshold slope(S.S.)降低了20 %左右。Tri-gate結構的S.S.相比於平面結構也降低了約22 %，汲極飽和電流也大約是平面結構的兩倍。最後是初步的討論元件閘極氧化層可靠度，在適當的Vg ,max下， NO製程的tri-gate MOSFET不僅有著最佳的電流特性，而且不論是PBTI、NBTI都有著最小的ΔVTH，然而，在動態導通電阻的穩定性有觀察到一些問題。

Due to the high Dit at the SiC/SiO2 interface, the channel mobility of conventional (0001) face low-voltage SiC MOSFETs is limited. In order to improve this issue, this work proposes a tri-gate structure which include the (112̅0) face sidewall as part of the channel. In addition, NO and N2O are used for post-oxidation annealing to reduce the Dit and their effects are compared.
N-type MOS capacitors, planar MOSFETs, and tri-gate MOSFETs are used to evaluate the characteristics of devices and compare them with different post-oxidation annealing. Compared to the N2O process, the Dit¬ value for (0001) face of the NO process at E-EC=0.1 eV is reduced by about 40%, and the sub-threshold slope (S.S.) is reduced by about 20 %. Compared to the planar structure, the S.S. of tri-gate structure is also reduced by about 22 %, and the drain saturation current is about twice as large as the planar structure. Finally, the preliminary reliability of the gate oxide is discussed. Tri-gate MOSFET with NO process not only has the best current characteristics, but also has the smallest ΔVTH for both PBTI and NBTI under a reasonable Vg,max. However, some dynamic Ron issue is observed.

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