Impact of Self-Heating Effect on Hot Carrier Degradation in High-Voltage LDMOS

Self-heating induced transient hot carrier effects in high-voltage n-LDMOS are investigated. A novel LDMOS structure incorporating a metal contact in the bird´s beak region is fabricated, which allows us to probe an internal voltage transient in hot carrier stress. The AC stress- frequency dependence of device degradation is characterized and evaluated by a two-dimensional numerical simulation. Our result shows that drain current degradation in AC stress is more serious than in DC stress because of the reduction of self-heating effect.