Enhanced low-temperature corner current-carrying inherent to shallow trench isolation (STI)

The subthreshold hump in the current-voltage (I-V) characteristics caused by the current-carrying corner in shallow-trench-isolated (STI) n-channel MOSFET's is significantly enhanced at reduced temperatures. Numerical simulations show that the sensitivity of the corner channel's threshold voltage to temperature is smaller than that of the center channel's threshold voltage. This, together with the reduced subthreshold swing at low temperatures, contribute to an enhanced subthreshold hump, and is potentially important for emerging cryogenic applications.