随机掺杂波动引起阈值电压偏离的统计分析

摘要

工艺参数波动和偏离已严重影响纳米集成电路制造性能和成品率,阈值电压是MOS集成电路设计中的重要参数,而随机掺杂工艺波动是引起阈值电压的偏离的一个重要因素.本文根据阈值电压的偏离的物理机制,通过统计分析的方法,推导随机掺杂波动引起阈值电压偏离标准差的简洁表达式,根据该公式计算了实际纳米工艺器件阈值电压偏离的标准差数据,该值接近40mV,该数据与相关工艺下其他论文的数据进行了对照,结果表明,本文采用统计学理论推导的公式不仅简洁而且能较精确的估算实际工艺下的阈值电压偏离情况和分布.%Process parameters fluctuations and variations have seriously affected the nanometer IC manufacturing performance and yield. Threshold voltage is an important parameter in MOS integrated circuit design and random doping fluctuations becomes an important factor for threshold voltage deviation. Based on the threshold voltage deviation from the physical mechanism, through statistical analysis method, we propose the simple standard deviation expression of threshold voltage deviation from the random doping fluctuations. According to the formula, we calculate the actual nano-MOSFET devices threshold voltage's standard deviation that is close to 40mV. The compared results from the data and related data in other papers show that the formula derived using statistical theory is not only simple but a very good estimation and distribution of threshold voltage deviations in actual process.