Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-...Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.展开更多
The MOSFET gate currents of high k gate dielectrics due to direct tunneling are investigated by using a new direct tunneling current model developed.The model includes both the inversion layer quantization effect with...The MOSFET gate currents of high k gate dielectrics due to direct tunneling are investigated by using a new direct tunneling current model developed.The model includes both the inversion layer quantization effect with finite barrier height and the polysilicon depletion effect.The impacts of dielectric constant and conduction band offset as well as the band gap on the gate current are discussed.The results indicate that the gate dielectric materials with higher dielectric constant,larger conduction band offset and the larger band gap are necessary to reduce the gate current.The calculated results can be used as a guide to select the appropriate high k gate dielectric materials for MOSFETs.展开更多
HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric const...HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric constant of 16.3 and low gate leakage current of 2.47×10-5 A/cm2 at E=5 MV/cm,which makes ALD HfxAl(1-x)O a great potential candidate gate dielectric for 4H-SiC MIS based transistors.展开更多
文摘Aim To study the dIelectric breakdown phenomenon in the materials with quenched disorder. Methods Renormolization group methods were used. Results The percolation limit for breakdown pc , the breakdown field Ec～(Pc-p)v, and the fractal dimension of the structure of dielectric breakdown df were obtained. Conclusion The breakdown properties of the materials with quenched disorder are characterized by universal power laws, where the exponents are universal.
文摘The MOSFET gate currents of high k gate dielectrics due to direct tunneling are investigated by using a new direct tunneling current model developed.The model includes both the inversion layer quantization effect with finite barrier height and the polysilicon depletion effect.The impacts of dielectric constant and conduction band offset as well as the band gap on the gate current are discussed.The results indicate that the gate dielectric materials with higher dielectric constant,larger conduction band offset and the larger band gap are necessary to reduce the gate current.The calculated results can be used as a guide to select the appropriate high k gate dielectric materials for MOSFETs.
基金supported by the National Natural Science Foundation of China (Grant No. 61006008)the National Defense Advance Research Project (Grant No. 513080301)the Key Specific Project in the National Sciences and Technology Program (Grant No. KJ080112501)
文摘HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric constant of 16.3 and low gate leakage current of 2.47×10-5 A/cm2 at E=5 MV/cm,which makes ALD HfxAl(1-x)O a great potential candidate gate dielectric for 4H-SiC MIS based transistors.
