Effect of p-well contact on n-well potential modulation in a 90 nm bulk technology

The effect of p-well contact on the n-well potential modulation in a 90 nm bulk technology with P+ deep well is studied based on three-dimensional (3-D) TCAD device simulations. Simulation results illustrate that the p-well contact area has a great impact on the n-well potential modulation and the enhancement factor will level out as the p-well contact area increases, and that at the same time the increase of p-well doping concentration can also enhance the n-well potential modulation. However, the effect of p-well contact location on the n-well modulation is not obvious as the p-well contact distance increases. According to our simulation results, it is proposed that the p-well contact area should be cautiously designed to mitigate single event effect (SEE) in the P+ deep well technology.