Development of an N-type DEMOS on a 0.6-µm platform for 18V analog & digital aplications

Anomalous hot-carrier induced on-resistance (Ron) and drive current degradations were observed in 18 V n-type Drain Extended MOS (DEMOS) devices with various n-type Drain Drift (NDD) implant dosages. Under the same stress conditions, the device with higher NDD dosage while showing a higher substrate current (Isub) results in lower Idsat and ON-resistance (Ron) degradations. Optimal conditions for NDD implant which shift the high electric field peak causing away from the surface were introduced using technology computer aided design (TCAD) simulations. Consequently hot carrier induced degradation was suppressed as was verified by silicon measurements.