A Solution Toward the OFF-State Degradation in Drain-Extended MOS Device

We investigated the surface band-to-band tunnelling (BTBT) current under the off-state condition in drain-extended MOS (DeMOS) devices. We found significant gate-induced drain leakage current due to surface BTBT, which was also reported earlier as the dominant cause of early time-dependent dielectric breakdown and device failure. Furthermore, a layout solution for the existing DeMOS device is proposed in order to mitigate the surface BTBT current and the associated gate oxide reliability issues, without sacrificing the mixed-signal performance of the device.