Capacitance–Frequency Estimates of Border-Trap Densities in Multifin MOS Capacitors

We use capacitance-frequency (C- f ) measurements to provide lower bound estimates of border-trap densities in multifin MOS capacitors with high-K dielectrics built in Ge and InGaAs fin field effect transistor (FinFET) technologies before and after X-ray irradiation. The C- f method is illustrated for SiO
₂
-based planar MOS capacitors and compared with highfrequency capacitance-voltage measurements. Lower effective border-trap densities are found before and after irradiation for multifin capacitors built in a strained Ge pMOS FinFET technology than for similar devices built using an early-developmental stage InGaAs MOS technology. These results show the utility of C- f measurements in characterizing defect densities in MOS capacitors, particularly when large border-trap densities exist.