共查询到18条相似文献,搜索用时 109 毫秒
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采用分子束外延方法在砷化镓衬底上生长了AlAs/GaAs双势垒量子阱薄膜结构。介绍了量子阱薄膜在单轴压力作用下的压阻实验,测试出薄膜在压力影响下的I-V曲线,并分析了量子阱薄膜压阻效应的成因。通过实验证实了量子阱薄膜具有较高灵敏度的压阻效应,其压阻灵敏度比目前常用的多晶硅的压阻灵敏度提高一个数量级。 相似文献
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本文首先系统的研究了用 LPCVD工艺在温度为 625℃、气相硼硅原子比分别为 1.6 × 10~(-3)和2.0×10~(-3)时淀积的、其后又分别经900℃、1050℃、1150℃ 10秒钟快速热退火(RTA)处理的多晶硅薄膜压阻特性.然后,基于上述结果,着重研究了气相硼硅原子比分别为 1.6×10~(-3)、2.0 × 10~(-3)、4.0 ×10~(-3)和5.0 × 10~(-3)时淀积,其后只经1150℃ 10秒钟快速热退火处理的多晶硅薄膜压阻特性.在上述淀积条件下,与900℃ 30分钟常规热退火(FA)相比较,得到了快速热退火的最佳条件. 相似文献
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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 of piezoresistance coefficients around grain boundaries was presented, and then the experiment results of polysilicon nanofilms were explained theoretically. 相似文献
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A theoretical model for piezoresistance in polysilicon is described. Grain size, orientation and doping dependence effects are included. Predictions of gauge factor using the model give reasonable agreement with experimental results and enable optimum processing parameters to be chosen for a given grain size. 相似文献
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Giora Yaron 《Solid-state electronics》1979,22(12):1017-1024
Thin (3000–5000Å) low pressure chemically vapor deposited (LPCVD) films of polycrystalline silicon suitable for microelectronics applications have been deposited from silane at 600°C and at a pressure of 0.25 Torr. The films were phosphorus implanted at 150 KeV and electrically characterized with the annealing conditions and film thickness as parameters, over a resistivity range of four orders of magnitude (103–107Ω/□). Annealing during silox deposition was found to result in a lower film resistivity than annealing done in nitrogen atmosphere. Resistivity measurements as a function of temperature indicate that the electrical activation energy is a linear function of 1/N(N is the doping concentration), changing from 0.056 eV for a doping concentration of 8.9 × 1018 cm−3 to 0.310 eV for doping concentration of 3.3 × 1018 cm−3. The grain boundary trap density was found to have a logarithmically decreasing dependence on the polysilicon thickness, decreasing from 1.3 × 1013 cm−2 for 2850Å polysilicon film to 8.3 × 1012 cm−2 for 4500Å polysilicon film. 相似文献
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《Electron Devices, IEEE Transactions on》2006,53(8):1885-1892
One of the key benefits of using polysilicon as the material for resistors and piezoresistors is that the temperature coefficient of resistivity (TCR) can be tailored to be negative, zero, or positive by adjusting the doping concentration. This paper focuses on optimization of the boron doping of low-pressure chemical vapor deposited polysilicon resistors for obtaining near-zero TCR and development of a physical model that explains quantitatively all the results obtained in the optimization experiments encompassing the doping concentration ranges that show negative, near-zero, and positive TCR values in the polysilicon resistors. The proposed model considers single-crystal silicon grain in equilibrium with amorphous silicon grain boundary. The grain boundary carrier concentration is calculated considering exponential band tails in the density of states for amorphous silicon in the grain boundaries. Comparison of the results from the model shows excellent agreement with the measured values of resistivity as well as TCR for heavily doped polysilicon. It is shown that the trap density for holes in the grain boundary increases as the square root of the doping concentration, which is consistent with the defect compensation model of doping in the amorphous silicon grain boundaries. 相似文献
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《Electron Devices, IEEE Transactions on》1981,28(7):818-830
The processing parameters of monolithic polycrystalline silicon resistors are examined, and the effect of grain size on the sensitivity of polysilicon resistivity versus doping concentration is studied theoretically and experimentally. Because existing models for polysilicon do not accurately predict resistivity dependence on doping concentration as grain size increases above 600 Å, a modified trapping model for polysilicon with different grain sizes and under various applied biases is introduced. Good agreement between theory and experiments demonstrates that an increase in grain size from 230 to 1220 Å drastically reduces the sensitivity of polysilicon resistivity to doping levels by two orders of magnitude. Such an increase is achieved by modifications of the integrated-circuit processes. Design criteria for the optimization of monolithic polysilicon resistors have also been established based on resistivity control, thermal properties, and device geometry. 相似文献
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Lhermite H. Bonnaud O. Colin Y. Rouffet A.M. 《Electron Devices, IEEE Transactions on》1988,35(5):675-683
An analysis of the field effect on small-grained (500-A) thin polysilicon film is carried out to predict the electrical behavior of metal-oxide-polysilicon structures, which depends on the grain size, the doping concentration of the polysilicon layer, and the trap densities at the grain boundaries. A one-dimensional model that is based on the exact numerical solution of Poisson's equation, which takes into account all of these parameters, is developed. Good agreement between experimental and calculated C (V ) curves is found 相似文献
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Mimura A. Kawachi G. Aoyama T. Suzuki T. Nagae Y. Konishi N. Mochizuki Y. 《Electron Devices, IEEE Transactions on》1993,40(3):513-520
A bucket-type high-density (0.25-1.2-mA/cm2) low-energy (500-2000 V) ion source was utilized for high-speed phosphorus doping directly into a thin polysilicon layer without cap SiO2. Doping gas with He dilution was selected to reduce etching of polysilicon film. Excimer laser (XeCl, 8 mm×8 mm) pulse annealing was introduced to activate effectively the doped impurity. The combination of these techniques provided a practically low sheet resistance for the TFT source, drain, and gate with a short time doping. The low-temperature polysilicon TFT fabricated with a doping time of 10 s had characteristics comparable to those of that fabricated by a longer time doping or conventional ion implantation, showing the practicality of this technology and its promise for giant microelectronics 相似文献
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《Electron Device Letters, IEEE》1985,6(6):313-315
An analytic model of p-channel polysilicon MOSFET operating in accumulation mode is presented. The measured device transfer characteristics, for passivated and unpassivated films, are quantitatively explained in terms of leakage, subthreshold, and drive regimes of operation. The observed current swing of 104is shown to result primarily from the gate-voltage-induced mobility enhancement. This enhancement, a unique feature of polysilicon, is quantified via electrostatic shielding and barrier-potential-dependent mobility. The model describes transconductance, drain admittance, and ON/OFF ratio as a function of grain size, trap density and level, film thickness, and doping concentration. 相似文献