摘要 |
A CMOS device includes a silicon substrate, a gate insulating film, and a gate electrode including a silicon layer doped with boron and phosphorous, a tungsten nitride layer and a tungsten layer. A ratio of a maximum boron concentration to a minimum boron concentration in a boron concentration profile across the thickness of the silicon layer is not higher than 100. The CMOS device has a lower NBTI (Negative Bias Temperature Instability) degradation.
|