Hot hole-induced device degradation by drain junction reverse current

In this paper, device degradation mechanisms by drain junction reverse current in the off-state were studied, using n-type metal-oxide-semiconductor field-effect transistor (N-MOSFET), which is used as the high-voltage core circuit of flash memory chip. Components of drain leakage currents in the off-state are gate-induced drain-leakage (GIDL) and drain junction reverse currents. Device degradation phenomenon and mechanism by GIDL in the MOSFETs have been well known, but those by drain junction reverse current have not. A variety of measurement conditions for separating drain junction reverse current from total drain current in the off-state were suggested, and hole injection phenomenon into the gate was investigated through the modified capacitive-voltage method. In addition, we investigated the location of electron-hole generation between GIDL and drain junction reverse current through the lateral profile of trapped hole extracted from charge pumping method.