Trap-Related Carrier Transports in p-Channel Field-Effect Transistor with Polycrystalline Si/HSiON Gate Stack

A microscopic investigation of gate leakage behaviors in metal–oxide–semiconductor field-effect transistors (MOSFETs) with polycrystalline Si/HfSiON high-k gate stacks was carried out by an electron-beam-induced current (EBIC) technique. The transport mechanisms of electrons and holes in nonbreakdown MOSFETs were clarified. Carrier separated measurement revealed that hole transport in pFETs is significantly enhanced by charged traps, while electron transport in nFETs appears to be independent of such traps. A detailed investigation on the trap-related carrier transport in pFETs was carried out employing EBIC observations and gate bias and acceleration voltage dependences.