The effects of several factors on mobility in 4H-SiC buried-channel （BC） MOSFETs are studied,A simple model that gives a quantitative analysis of series resistance effects on the effective mobility and field-effect ...The effects of several factors on mobility in 4H-SiC buried-channel （BC） MOSFETs are studied,A simple model that gives a quantitative analysis of series resistance effects on the effective mobility and field-effect mobility is proposed.A series resistance not only decreases field-effect mobility but also reduces the gate voltage corresponding to the peak field-effect mobility. The dependence of the peak field-effect mobility on series resistance follows a simple quadratic polynomial. The effects of uniform and exponential interface state distributions in the forbidden band on field-effect mobility are analyzed with an analytical model. The effects of non-uniform interface states can be ignored at lower gate voltages but become more obvious as the gate bias increases.展开更多
The buried channel (BC) nMOSFETs with gate oxide grown thermally on 4H-SiC are fabricated.The BC region and source/drain region are formed by nitrogen implantation at room temperature followed by annealing at 1600℃.T...The buried channel (BC) nMOSFETs with gate oxide grown thermally on 4H-SiC are fabricated.The BC region and source/drain region are formed by nitrogen implantation at room temperature followed by annealing at 1600℃.The channel depth is about 0.2μm.The peak field-effect mobility of 18.1cm2/(V·s) for 5μm device is achieved.Thickly dotted pits found in the surface through microscope may be one of the important factors of the cause low field-effect mobility.The threshold voltages are 1.73V and 1.72V for the gate lengths of 3μm and 5μm respectively.The transconductance at V G=20V and V D=10V is 102μS for the gate length of 3μm.展开更多
文摘The effects of several factors on mobility in 4H-SiC buried-channel （BC） MOSFETs are studied,A simple model that gives a quantitative analysis of series resistance effects on the effective mobility and field-effect mobility is proposed.A series resistance not only decreases field-effect mobility but also reduces the gate voltage corresponding to the peak field-effect mobility. The dependence of the peak field-effect mobility on series resistance follows a simple quadratic polynomial. The effects of uniform and exponential interface state distributions in the forbidden band on field-effect mobility are analyzed with an analytical model. The effects of non-uniform interface states can be ignored at lower gate voltages but become more obvious as the gate bias increases.
文摘The buried channel (BC) nMOSFETs with gate oxide grown thermally on 4H-SiC are fabricated.The BC region and source/drain region are formed by nitrogen implantation at room temperature followed by annealing at 1600℃.The channel depth is about 0.2μm.The peak field-effect mobility of 18.1cm2/(V·s) for 5μm device is achieved.Thickly dotted pits found in the surface through microscope may be one of the important factors of the cause low field-effect mobility.The threshold voltages are 1.73V and 1.72V for the gate lengths of 3μm and 5μm respectively.The transconductance at V G=20V and V D=10V is 102μS for the gate length of 3μm.
