Tunnelling Injection in Thin Oxide MOS Capacitors

In this paper the semi-classical and quantum-mechanical definitions of escape-time from quasi-bound states have been compared in the frame of MOSFET gate leakage-current calculations. The theoretical background and the numerical issues involved in the implementation of these approaches inside device simulators have been compared. Results on many different thin gate-oxide capacitors, and on a special purpose test structure with mercury-probe contact, point out that the semi-classical approach is faster, less demanding from the numerical point of view, and surprisingly accurate compared to the fully quantum-mechanical treatment of more physically-sound models.