Abstract： This paper presents a novel poly （PC） and active （RX） comer rounding modeling approach to SPICE simulations. A set of specially designed structures was used for measurement data collection. PC and RX co...Abstract： This paper presents a novel poly （PC） and active （RX） comer rounding modeling approach to SPICE simulations. A set of specially designed structures was used for measurement data collection. PC and RX comer rounding equations have been derived based on an assumption that the comer rounding area is a fragment of a circle. The equations were modified to reflect the gouging effect of physical silicon wafers. The modified general equations were implemented in the SPICE model to enable the model to describe the comer rounding effect. The good fittings between the SPICE model simulation results and the silicon data demonstrated in this paper proved that the designed comer rounding model is practical and accurate. Key words： SPICE model; MOSFETs; poly and active; comer rounding; nanometer technology展开更多
In this paper, an aeronautical thin-walled part with a complex geometry which has several sharp bends and curvatures in different directions was investigated. This kind of part is difficult to be manufactured only in ...In this paper, an aeronautical thin-walled part with a complex geometry which has several sharp bends and curvatures in different directions was investigated. This kind of part is difficult to be manufactured only in one stage. Therefore, an innovative multi-stage active hydroforming process assisted by the rigid forming method was designed. In addition, an optimized blank geometry is obtained. In fact, the main focused point of this paper is to propose a new small radius rounded corner forming technique and analyze the mechanism. Two kinds of forming modes of changing a big rounded corner into a small one, which are related to different tangential positions of the die in the process of calibration, are analyzed theoretically. Meanwhile, the stress and strain states of the deformation region are compared. The relationships between the minimum relative radii of rounded corners I and II in the first stage and the hydraulic pressure are calculated by the bending theory. Finally, the influences of the tensile-bulging effect and the interface condition of the double-layer sheet on the forming quality of the specimen are investigated. The achieved results can make a foundation for utilizing the proposed method in forming of thin-walled parts with very small radii.展开更多
文摘Abstract： This paper presents a novel poly （PC） and active （RX） comer rounding modeling approach to SPICE simulations. A set of specially designed structures was used for measurement data collection. PC and RX comer rounding equations have been derived based on an assumption that the comer rounding area is a fragment of a circle. The equations were modified to reflect the gouging effect of physical silicon wafers. The modified general equations were implemented in the SPICE model to enable the model to describe the comer rounding effect. The good fittings between the SPICE model simulation results and the silicon data demonstrated in this paper proved that the designed comer rounding model is practical and accurate. Key words： SPICE model; MOSFETs; poly and active; comer rounding; nanometer technology
基金supported by the National Science and Technology Major Project of China (No. 2014ZX04002041)
文摘In this paper, an aeronautical thin-walled part with a complex geometry which has several sharp bends and curvatures in different directions was investigated. This kind of part is difficult to be manufactured only in one stage. Therefore, an innovative multi-stage active hydroforming process assisted by the rigid forming method was designed. In addition, an optimized blank geometry is obtained. In fact, the main focused point of this paper is to propose a new small radius rounded corner forming technique and analyze the mechanism. Two kinds of forming modes of changing a big rounded corner into a small one, which are related to different tangential positions of the die in the process of calibration, are analyzed theoretically. Meanwhile, the stress and strain states of the deformation region are compared. The relationships between the minimum relative radii of rounded corners I and II in the first stage and the hydraulic pressure are calculated by the bending theory. Finally, the influences of the tensile-bulging effect and the interface condition of the double-layer sheet on the forming quality of the specimen are investigated. The achieved results can make a foundation for utilizing the proposed method in forming of thin-walled parts with very small radii.
