An investigation was made into the effect of doping with the elemental crystal Ge or/and GeO2 on the TiO2-V2O5-Y2O3 varistor ceramics. The result shows that as the doping contents of V2O5 and Y2O3 are 0.5 tool%, respe...An investigation was made into the effect of doping with the elemental crystal Ge or/and GeO2 on the TiO2-V2O5-Y2O3 varistor ceramics. The result shows that as the doping contents of V2O5 and Y2O3 are 0.5 tool%, respectively, co-doping with 0.3 mol% Ge and 0.9 mol% GeO2 makes the highest α value （α = 12.8）, the lowest breakdown voltage Vlmg （VlmA = 15.8 V/ram） and the highest grain boundary barrier ФB （ФB = 1.48 eV）, which is remarkably superior to the TiO2-V2Os-Y203 varistor ceramics undoped with Ge and GeO2 and mono-doped with Ge or GeO2. The TiO2-V2Os-YEO3-Ge-GeO2 ceramic has the prospect of becoming a novel varistor ceramic with excellent electrical properties.展开更多
On the basis of thermodynamic and kinetic consideration of Ge-O system,high-pressure oxidation(HPO)on Ge was proposed to suppress the GeO desorption during the thermal oxidation and significant improvements of Ge/GeO2...On the basis of thermodynamic and kinetic consideration of Ge-O system,high-pressure oxidation(HPO)on Ge was proposed to suppress the GeO desorption during the thermal oxidation and significant improvements of Ge/GeO2-based gate stacks have been achieved.It is found that the post oxidation annealing at lower temperatures is helpful to passivate the interface defects at the Ge/GeO2 stack generated by the conventional thermal oxidation,while the high-quality GeO2 bulk properties can only be achieved by HPO that grows GeO2 film at high temperatures without the GeO desorption.This paper reviews the advantage of HPO on the formation of Ge/GeO2 stacks in terms of Ge/GeO2 interface and GeO2 bulk properties.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.51262017,51362017)
文摘An investigation was made into the effect of doping with the elemental crystal Ge or/and GeO2 on the TiO2-V2O5-Y2O3 varistor ceramics. The result shows that as the doping contents of V2O5 and Y2O3 are 0.5 tool%, respectively, co-doping with 0.3 mol% Ge and 0.9 mol% GeO2 makes the highest α value （α = 12.8）, the lowest breakdown voltage Vlmg （VlmA = 15.8 V/ram） and the highest grain boundary barrier ФB （ФB = 1.48 eV）, which is remarkably superior to the TiO2-V2Os-Y203 varistor ceramics undoped with Ge and GeO2 and mono-doped with Ge or GeO2. The TiO2-V2Os-YEO3-Ge-GeO2 ceramic has the prospect of becoming a novel varistor ceramic with excellent electrical properties.
基金The author would like to thank Prof.Akira Toriumi,Prof.Kita Koji,Prof.Kosuke Nagashio,and Dr.Tomonori Nishimura at the University of Tokyo for their continuous support and encouragement,which induced the main results reviewed in this paper.
文摘On the basis of thermodynamic and kinetic consideration of Ge-O system,high-pressure oxidation(HPO)on Ge was proposed to suppress the GeO desorption during the thermal oxidation and significant improvements of Ge/GeO2-based gate stacks have been achieved.It is found that the post oxidation annealing at lower temperatures is helpful to passivate the interface defects at the Ge/GeO2 stack generated by the conventional thermal oxidation,while the high-quality GeO2 bulk properties can only be achieved by HPO that grows GeO2 film at high temperatures without the GeO desorption.This paper reviews the advantage of HPO on the formation of Ge/GeO2 stacks in terms of Ge/GeO2 interface and GeO2 bulk properties.
