Forward-bias tunneling: A limitation to bipolar device scaling

  title={Forward-bias tunneling: A limitation to bipolar device scaling},
  author={J. A. del Alamo and R G Swanson},
  journal={IEEE Electron Device Letters},
Forward-bias tunneling is observed in heavily doped p-n junctions of bipolar transistors. A simple phenomenological model suitable to incorporation in device codes is developed. The model identifies as key parameters the space-charge-region (SCR) thickness at zero bias and the reduced doping level at its edges which can both be obtained from CV characteristics. This tunneling mechanism may limit the maximum gain achievable from scaled bipolar devices.