Time-dependent defect spectroscopy for characterization of border traps in metal-oxide-semiconductor transistors

Abstract

We introduce the time-dependent defect spectroscopy (TDDS) for the analysis of a particular class of oxide defects known as ``border traps.'' These defects have a fundamental impact on the behavior of metal-oxide-semiconductor field-effect transistors and are commonly linked to the occurrence of random-telegraph noise, $1/f$ noise, and slow charging transients. The TDDS naturally extends the successful deep-level transient spectroscopy as it extracts both the capture and emission time constants. Analysis proceeds via the so-called spectral maps, which separate individual border traps by their characteristic times and their voltage step height. In contrast to standard random-telegraph noise analysis methods, where uncorrelated capture and emission events of only a few traps can already create convoluted noise patterns, the synchronization by the charging pulse yields the spectral maps, which allow for the analysis of a large number of defect occupancies in a single measurement. As a consequence, the TDDS allows us to monitor the defect parameters over exceptionally wide temperature and bias ranges.