Threshold Voltage Model Of Short-channel MOSFET's

The quick development of the integrated circuits requires higher performance device that has high speed, small size and low power consumption. From the physics of semiconductor devices view, the size of device is smaller, so transit time is shorter and speed is faster, at the same time, the impact among mobile carriers is more decreased, that results in lower power consumption. In summary, we can get higher speed and lower power consumption by reducing the size of the transistors. When device dimensions have been scaled down, while the power supply and the operating voltage have not been decreased, it will lead to the secondary effects. The secondary effects affect the reliability and yield. In order to predict the characteristics of the circuits and guide the new technology development, a new model, which is simple and accurate, is needed.The theory of work operation and threshold voltage model for MOSFET are been made a deep study in the article. A new and simplified threshold voltage model is derived from the basically characteristics of semiconductor, based on the measured data from 1um 5 V CMOS process and the feature of the MOSFEET. What the work consists mainly of are as follows:1. The principle of work and threshold voltage model for MOSFET, which is doped uniformly in the substrate, are been made a deep study. And we advanced a new and simplified model for threshold voltage of short-channel MOSFET by revising ideal MOSFET, which according to the feature of the MOSFET.2. Extract the parameters of the typical lum 5V CMOS device and simulate typical lum 5V CMOS device using simplified model for short-channel threshold voltage. The simulated result indicates simplified model for short-channei threshold voitage has higher accuracy.3. Analysis simplified model for short-channel threshold voltage and study the influencing factors of threshold voltage for short-channel MOSFET on the base of the simplified threshold voltage model. We develop an optimal design for threshold voltage in 0.8um 5V CMOS process. In order to good device performance, we take other factors into consideration.