The experiment results indicate that the gauge factor of highly boron doped polysilicon nanofilm is bigger than that of monocrystalline silicon with the same doping concentration, and increases with the grain size dec...The experiment results indicate that the gauge factor of highly boron doped polysilicon nanofilm is bigger than that of monocrystalline silicon with the same doping concentration, and increases with the grain size decreasing. To apply the unique properties reasonably in the fabrication of piezoresistive devices, it was expounded based on the analysis of energy band structure that the properties were caused by the tunnel current which varies with the strain change forming a tunnelling piezoresistive effect. Finally, a calculation method ofpiezoresistance coefficients around grain boundaries was presented, and then the experiment results ofpolysilicon nanofilms were explained theoretically.展开更多
Based on the trap model, the band structure and the conductive mechanism ofpolysilicon were analyzed, and then an equivalent circuit used to interpret the tunneling piezoresistive effect was proposed. Synthesizing the...Based on the trap model, the band structure and the conductive mechanism ofpolysilicon were analyzed, and then an equivalent circuit used to interpret the tunneling piezoresistive effect was proposed. Synthesizing the piezoresistive effect of the grain boundary region and grain neutral zone, a new piezoresistive model--a tunneling piezoresistive model is established. The results show that when the doping concentration is above 10^20 cm^-3, the piezoresistive coefficient of the grain boundary is higher than that of the neutral zone, and it increases with an increase in doping concentration. This reveals the intrinsic mechanism of an important experimental phenomena that the gauge factor of heavily doped polysilicon nano-films increases with an increase in doping concentration.展开更多
基金supported by the National Natural Science Foundation of China(No.60776049)the Science and Technology Foundation of Liaoning Province ofChina(No.20072036)the Fund ofLiaoning Province Education Department of China(No.2007T130).
文摘The experiment results indicate that the gauge factor of highly boron doped polysilicon nanofilm is bigger than that of monocrystalline silicon with the same doping concentration, and increases with the grain size decreasing. To apply the unique properties reasonably in the fabrication of piezoresistive devices, it was expounded based on the analysis of energy band structure that the properties were caused by the tunnel current which varies with the strain change forming a tunnelling piezoresistive effect. Finally, a calculation method ofpiezoresistance coefficients around grain boundaries was presented, and then the experiment results ofpolysilicon nanofilms were explained theoretically.
基金supported by the National Natural Science Foundation of China(No.60776049)the Science and Technology Foundation of Liaoning Province(No.20072036)the Fund of Liaoning Province Education Department(No.2007T130)
文摘Based on the trap model, the band structure and the conductive mechanism ofpolysilicon were analyzed, and then an equivalent circuit used to interpret the tunneling piezoresistive effect was proposed. Synthesizing the piezoresistive effect of the grain boundary region and grain neutral zone, a new piezoresistive model--a tunneling piezoresistive model is established. The results show that when the doping concentration is above 10^20 cm^-3, the piezoresistive coefficient of the grain boundary is higher than that of the neutral zone, and it increases with an increase in doping concentration. This reveals the intrinsic mechanism of an important experimental phenomena that the gauge factor of heavily doped polysilicon nano-films increases with an increase in doping concentration.
