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In this thesis, the variation of the carrier distribution in the inversion layer by quantum mechanics for B+ and BF2+ channel implantation is researched in detail. The carrier mobility which considers the above-mentioned variation and normal field mobility degradation is more complete and accurate than the conventional one in MINIMOS. The simulation results of the mobility model show that there is about 10% error in the measurements. The modified mobility model which fitted by the experiments can reduce the error to below 3%. From the comparison of the mobility between B+ and BF2+ channel implantation, an optimal channel implantation to get the higher mobility is obtained.
The basic scaling laws contain constant field, constant voltage and quasi-constant voltage, which have a lower mobility degradation and lower saturation current. From the point of view of speed, a new scaling law which has a lighter scaled voltage and a greater scaled gate oxide thickness than the basic scaling laws is proposed. The comparisons between the basic scaling laws and the new one in saturation current, mobility, and circuit speed of TISA (Timing Synthesis and analysis) are used to find an optimal scaling law. The results of simulation reveal that new scaling law which with a larger mobility degradation and higher saturation current gets the better circuit speed, and a maximum increase ratio in circuit speed. Therefore, the new scaling is obtained which can be used in designing of high-speed CMOS.
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