The interracial and electrical characteristics of Ge metal-oxide-semiconductor （MOS） devices with a dual passivation layer of ZrON/GeON formed by NH3- or N2-plasma treatment are investigated. The experimental result...The interracial and electrical characteristics of Ge metal-oxide-semiconductor （MOS） devices with a dual passivation layer of ZrON/GeON formed by NH3- or N2-plasma treatment are investigated. The experimental results show that the NH3-plasma treated sample exhibits significantly improved interfacial and electrical properties as compared to the samples with N2-plasma treatment and no treatment： a lower interface-state density at the midgap （1.64 × 1011 cm-2, eV- 1） and gate leakage current （9.32 × 10-5 A/cm2 at Vfb ＋ 1 V）, a small capacitance equivalent thickness （1.11nm） and a high k value （32）. X-ray photoelectron spectroscopy is used to analyze the involved mechanisms. It is indicated that more GeON and less GeOx （x 〈 2） are formed on the Ge surface during NH3-plasma treatment than the NE-plasma treatment, resulting in a high-quality high-k/Ge interface, because H atoms and NH radicals in NHa-plasma can enhance volatilization of the unstable low-k GeOx, creating high-quality GeON passivation layer. Moreover, more nitrogen incorporation in ZrON/GeON induced by NHa-plasma treatment can build a stronger N barrier and thus more effectively inhibit in-diffusion of O and Ti from high-k gate dielectric and out-diffusion of Ge.展开更多
A physical model of hole mobility for germanium-on-insulator p MOSFETs is built by analyzing all kinds of scattering mechanisms, and a good agreement of the simulated results with the experimental data is achieved, co...A physical model of hole mobility for germanium-on-insulator p MOSFETs is built by analyzing all kinds of scattering mechanisms, and a good agreement of the simulated results with the experimental data is achieved, confirming the validity of this model. The scattering mechanisms involved in this model include acoustic phonon scattering, ionized impurity scattering, surface roughness scattering, coulomb scattering and the scattering caused by Ge film thickness fluctuation. The simulated results show that the coulomb scattering from the interface charges is responsible for the hole mobility degradation in the low-field regime and the surface roughness scattering limits the hole mobility in the high-field regime. In addition, the effects of some factors, e.g. temperature, doping concentration of the channel and the thickness of Ge film, on degradation of the mobility are also discussed using the model, thus obtaining a reasonable range of the relevant parameters.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.6127411261176100,61404055)
文摘The interracial and electrical characteristics of Ge metal-oxide-semiconductor （MOS） devices with a dual passivation layer of ZrON/GeON formed by NH3- or N2-plasma treatment are investigated. The experimental results show that the NH3-plasma treated sample exhibits significantly improved interfacial and electrical properties as compared to the samples with N2-plasma treatment and no treatment： a lower interface-state density at the midgap （1.64 × 1011 cm-2, eV- 1） and gate leakage current （9.32 × 10-5 A/cm2 at Vfb ＋ 1 V）, a small capacitance equivalent thickness （1.11nm） and a high k value （32）. X-ray photoelectron spectroscopy is used to analyze the involved mechanisms. It is indicated that more GeON and less GeOx （x 〈 2） are formed on the Ge surface during NH3-plasma treatment than the NE-plasma treatment, resulting in a high-quality high-k/Ge interface, because H atoms and NH radicals in NHa-plasma can enhance volatilization of the unstable low-k GeOx, creating high-quality GeON passivation layer. Moreover, more nitrogen incorporation in ZrON/GeON induced by NHa-plasma treatment can build a stronger N barrier and thus more effectively inhibit in-diffusion of O and Ti from high-k gate dielectric and out-diffusion of Ge.
基金Project supported by the National Natural Science Foundation of China(Nos.61274112,61176100,61404055)
文摘A physical model of hole mobility for germanium-on-insulator p MOSFETs is built by analyzing all kinds of scattering mechanisms, and a good agreement of the simulated results with the experimental data is achieved, confirming the validity of this model. The scattering mechanisms involved in this model include acoustic phonon scattering, ionized impurity scattering, surface roughness scattering, coulomb scattering and the scattering caused by Ge film thickness fluctuation. The simulated results show that the coulomb scattering from the interface charges is responsible for the hole mobility degradation in the low-field regime and the surface roughness scattering limits the hole mobility in the high-field regime. In addition, the effects of some factors, e.g. temperature, doping concentration of the channel and the thickness of Ge film, on degradation of the mobility are also discussed using the model, thus obtaining a reasonable range of the relevant parameters.
