Hot Carrier Reliability of Strained N-Mosfet with Lattice Mismatched Source/Drain Stressors

The hot carrier reliability of a novel uniaxial tensile strained n-channel transistor with silicon-carbon (Si<sub>1 </sub>-<sub>y</sub>C<sub>y</sub>) source and drain (S/D) regions is investigated for the first time. Strained n-FETs show reduced hot carrier lifetime than the control n-FETs when stressed at comparable I<sub>sub</sub>/I<sub>d</sub> ratio. Worst case hot carrier stressing is observed to occur at maximum substrate current I<sub>sub</sub> condition which leads to a higher drive current I<sub>Dsat</sub> degradation as compared to the V<sub>GS</sub> = V<sub>GS</sub> stress. At nominal operating voltages, the strained n-FET is projected to have a hot carrier lifetime well exceeding the 10-years requirement, showing no severe reliability issues.

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