Nitrogen plasma passivation （NPP） on （111） germanium （Ge） was studied in terms of the interface trap density, roughness, and interfacial layer thickness using plasma-enhanced chemical vapor deposition （PECVD）....Nitrogen plasma passivation （NPP） on （111） germanium （Ge） was studied in terms of the interface trap density, roughness, and interfacial layer thickness using plasma-enhanced chemical vapor deposition （PECVD）. The results show that NPP not only reduces the interface states, but also improves the surface roughness of Ge, which is beneficial for suppressing the channel scattering at both low and high field regions of Ge MOSFETs. However, the interracial layer thickness is also increased by the NPP treatment, which will impact the equivalent oxide thickness （EOT） scaling and thus degrade the device performance gain from the improvement of the surface morphology and the interface passivation. To obtain better device performance of Ge MOSFETs, suppressing the interfacial layer regrowth as well as a trade-off with reducing the interface states and roughness should be considered carefully when using the NPP process.展开更多
基金supported by the National Basic Research Program of China(Grant No.2011CBA00601)the National Science and Technology Major Project of the Ministry of Science and Technology of China(Grant No.2009ZX02035-001)the National Natural Science Foundation of China(Grant Nos.60625403,60806033,and 60925015)
文摘Nitrogen plasma passivation （NPP） on （111） germanium （Ge） was studied in terms of the interface trap density, roughness, and interfacial layer thickness using plasma-enhanced chemical vapor deposition （PECVD）. The results show that NPP not only reduces the interface states, but also improves the surface roughness of Ge, which is beneficial for suppressing the channel scattering at both low and high field regions of Ge MOSFETs. However, the interracial layer thickness is also increased by the NPP treatment, which will impact the equivalent oxide thickness （EOT） scaling and thus degrade the device performance gain from the improvement of the surface morphology and the interface passivation. To obtain better device performance of Ge MOSFETs, suppressing the interfacial layer regrowth as well as a trade-off with reducing the interface states and roughness should be considered carefully when using the NPP process.
