中国物理B ›› 2017, Vol. 26 ›› Issue (10): 107101-107101.doi: 10.1088/1674-1056/26/10/107101
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
Zhan-Wei Shen(申占伟), Feng Zhang(张峰), Sima Dimitrijev, Ji-Sheng Han(韩吉胜), Guo-Guo Yan(闫果果), Zheng-Xin Wen(温正欣), Wan-Shun Zhao(赵万顺), Lei Wang(王雷), Xing-Fang Liu(刘兴昉), Guo-Sheng Sun(孙国胜), Yi-Ping Zeng(曾一平)
Zhan-Wei Shen(申占伟)1, Feng Zhang(张峰)1,3, Sima Dimitrijev2, Ji-Sheng Han(韩吉胜)2, Guo-Guo Yan(闫果果)1, Zheng-Xin Wen(温正欣)1, Wan-Shun Zhao(赵万顺)1, Lei Wang(王雷)1, Xing-Fang Liu(刘兴昉)1, Guo-Sheng Sun(孙国胜)1,3, Yi-Ping Zeng(曾一平)1,3
摘要:
The interface properties and electrical characteristics of the n-type 4H-SiC planar and trench metal-oxide-semiconductor (MOS) capacitors are investigated by measuring the capacitance voltage and current voltage. The flat-band voltage and interface state density are evaluated by the quasi-static method. It is not effective on further improving the interface properties annealing at 1250 ℃ in NO ambient for above 1 h due to the increasing interface shallow and fast states. These shallow states reduce the effective positive fixed charge density in the oxide. For the vertical MOS capacitors on the (1120) and (1100) faces, the interface state density can be reduced by approximately one order of magnitude, in comparison to the result of the planar MOS capacitors on the (0001) face under the same NO annealing condition. In addition, it is found that Fowler-Nordheim tunneling current occurs at an oxide electric field of 7 MV/cm for the planar MOS device. However, Poole-Frenkel conduction current occurs at a lower electric field of 4 MV/cm for the trench MOS capacitor. This is due to the local field crowded at the trench corner severely causing the electrons to be early captured at or emitted from the SiO2/SiC interface. These results provide a reference for an in-depth understanding of the mobility-limiting factors and long term reliability of the trench and planar SiO2/SiC interfaces.
中图分类号: (Semiconductor compounds)