High-k gate dielectric Hf Ti ON Ga As metal-oxide–semiconductor（MOS） capacitors with La ON as interfacial passivation layer（IPL） and NH3- or N2-plasma surface pretreatment are fabricated, and their interfacial an...High-k gate dielectric Hf Ti ON Ga As metal-oxide–semiconductor（MOS） capacitors with La ON as interfacial passivation layer（IPL） and NH3- or N2-plasma surface pretreatment are fabricated, and their interfacial and electrical properties are investigated and compared with their counterparts that have neither La ON IPL nor surface treatment. It is found that good interface quality and excellent electrical properties can be achieved for a NH3-plasma pretreated Ga As MOS device with a stacked gate dielectric of Hf Ti ON/La ON. These improvements should be ascribed to the fact that the NH3-plasma can provide H atoms and NH radicals that can effectively remove defective Ga/As oxides. In addition, La ON IPL can further block oxygen atoms from being in-diffused, and Ga and As atoms from being out-diffused from the substrate to the high-k dielectric. This greatly suppresses the formation of Ga/As native oxides and gives rise to an excellent high-k/Ga As interface.展开更多
NH3-plasma treatment is used to improve the quality of the gate dielectric and interface. Al2O3 is adopted as a buffer layer between HfO2 and MoS2 to decrease the interface-state density. Four groups of MOS capacitors...NH3-plasma treatment is used to improve the quality of the gate dielectric and interface. Al2O3 is adopted as a buffer layer between HfO2 and MoS2 to decrease the interface-state density. Four groups of MOS capacitors and back-gate transistors with different gate dielectrics are fabricated and their C–V and I–V characteristics are compared. It is found that the Al2O3/HfO2 back-gate transistor with NH3-plasma treatment shows the best electrical performance: high on–off current ratio of 1.53 × 107, higher field-effect mobility of 26.51 cm2/V·s, and lower subthreshold swing of 145 m V/dec.These are attributed to the improvements of the gate dielectric and interface qualities by the NH3-plasma treatment and the addition of Al2O3 as a buffer layer.展开更多
The effects of different NH3-plasma treatment procedures on interracial and electrical properties of Ge MOS capacitors with stacked gate dielectric of HtTiON/TaON were investigated. The NH3-plasma treatment was perfor...The effects of different NH3-plasma treatment procedures on interracial and electrical properties of Ge MOS capacitors with stacked gate dielectric of HtTiON/TaON were investigated. The NH3-plasma treatment was performed at different steps during fabrication of the stacked gate dielectric, i.e. before or after interlayer （TaON） deposition, or after deposition ofhigh-k dielectric （HfriON）. It was found that the excellent interface quality with an interface-state density of 4.79 × 101l eV-lcm-2 and low gate leakage current （3.43 ×10-5 A/cm2 at Vg = 1 V） could be achieved for the sample with NH3-plasma treatment directly on the Ge surface before TaON deposition. The involved mechanisms are attributed to the fact that the NH3-plasma can directly react with the Ge surface to form more Ge-N bonds, i.e. more GeOxNy, which effectively blocks the inter-diffusion of elements and suppresses the formation of unstable GeOx interfacial layer, and also passivates oxygen vacancies and dangling bonds near/at the interface due to more N incorporation and decomposed H atoms from the NH3-plasma.展开更多
The GaAs MOS capacitor was fabricated with HfTiON as high-k gate dielectric and NH3-plasma-treated ZnON as interfacial passivation layer （IPL）, and its interracial and electrical properties are investigated compared...The GaAs MOS capacitor was fabricated with HfTiON as high-k gate dielectric and NH3-plasma-treated ZnON as interfacial passivation layer （IPL）, and its interracial and electrical properties are investigated compared to its counterparts with ZnON IPL but no NH3-plasma treatment and without ZnON IPL and no plasma treatment. Experimental results show that low interface-state density near midgap （1.17×10^12 cm^-2eV^-1） and small gate leakage current density have been achieved for the GaAs MOS device with the stacked gate dielectric of Hf-TiON/ZnON plus NH3-plasma treatment. These improvements could be ascribed to the fact that the ZnON IPL can effectively block in-diffusion of oxygen atoms and out-diffusion of Ga and As atoms, and the NH3-plasma treatment can provide not only N atoms but also H atoms and NH radicals, which is greatly beneficial to removal of defective Ga/As oxides and As-As band, giving a high-quality ZnON/GaAs interface.展开更多
The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatal...The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61176100 and 61274112)
文摘High-k gate dielectric Hf Ti ON Ga As metal-oxide–semiconductor（MOS） capacitors with La ON as interfacial passivation layer（IPL） and NH3- or N2-plasma surface pretreatment are fabricated, and their interfacial and electrical properties are investigated and compared with their counterparts that have neither La ON IPL nor surface treatment. It is found that good interface quality and excellent electrical properties can be achieved for a NH3-plasma pretreated Ga As MOS device with a stacked gate dielectric of Hf Ti ON/La ON. These improvements should be ascribed to the fact that the NH3-plasma can provide H atoms and NH radicals that can effectively remove defective Ga/As oxides. In addition, La ON IPL can further block oxygen atoms from being in-diffused, and Ga and As atoms from being out-diffused from the substrate to the high-k dielectric. This greatly suppresses the formation of Ga/As native oxides and gives rise to an excellent high-k/Ga As interface.
基金Project supported by the National Natural Science Foundation of China(Grant No.61774064)
文摘NH3-plasma treatment is used to improve the quality of the gate dielectric and interface. Al2O3 is adopted as a buffer layer between HfO2 and MoS2 to decrease the interface-state density. Four groups of MOS capacitors and back-gate transistors with different gate dielectrics are fabricated and their C–V and I–V characteristics are compared. It is found that the Al2O3/HfO2 back-gate transistor with NH3-plasma treatment shows the best electrical performance: high on–off current ratio of 1.53 × 107, higher field-effect mobility of 26.51 cm2/V·s, and lower subthreshold swing of 145 m V/dec.These are attributed to the improvements of the gate dielectric and interface qualities by the NH3-plasma treatment and the addition of Al2O3 as a buffer layer.
基金supported by the National Natural Science Foundation of China(Nos.61176100,61274112)
文摘The effects of different NH3-plasma treatment procedures on interracial and electrical properties of Ge MOS capacitors with stacked gate dielectric of HtTiON/TaON were investigated. The NH3-plasma treatment was performed at different steps during fabrication of the stacked gate dielectric, i.e. before or after interlayer （TaON） deposition, or after deposition ofhigh-k dielectric （HfriON）. It was found that the excellent interface quality with an interface-state density of 4.79 × 101l eV-lcm-2 and low gate leakage current （3.43 ×10-5 A/cm2 at Vg = 1 V） could be achieved for the sample with NH3-plasma treatment directly on the Ge surface before TaON deposition. The involved mechanisms are attributed to the fact that the NH3-plasma can directly react with the Ge surface to form more Ge-N bonds, i.e. more GeOxNy, which effectively blocks the inter-diffusion of elements and suppresses the formation of unstable GeOx interfacial layer, and also passivates oxygen vacancies and dangling bonds near/at the interface due to more N incorporation and decomposed H atoms from the NH3-plasma.
基金supported by the National Natural Science Foundation of China(Nos.61176100,61274112,61404055)
文摘The GaAs MOS capacitor was fabricated with HfTiON as high-k gate dielectric and NH3-plasma-treated ZnON as interfacial passivation layer （IPL）, and its interracial and electrical properties are investigated compared to its counterparts with ZnON IPL but no NH3-plasma treatment and without ZnON IPL and no plasma treatment. Experimental results show that low interface-state density near midgap （1.17×10^12 cm^-2eV^-1） and small gate leakage current density have been achieved for the GaAs MOS device with the stacked gate dielectric of Hf-TiON/ZnON plus NH3-plasma treatment. These improvements could be ascribed to the fact that the ZnON IPL can effectively block in-diffusion of oxygen atoms and out-diffusion of Ga and As atoms, and the NH3-plasma treatment can provide not only N atoms but also H atoms and NH radicals, which is greatly beneficial to removal of defective Ga/As oxides and As-As band, giving a high-quality ZnON/GaAs interface.
文摘The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.
