Hi, When I looked at the layouts of CMOS, I often found pfets are surrounded by deep trenches. Is it required or not? If I only use pfets for low frequency application, can I ignore the deep trenches? If I have high frequency signals around CMOS, I think it's better to use a deep trench wall to enclose all the pfets and nfets. Thus they will not be affected by the high frequency signals, am I right? sincerely
