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Updated: Aug 11, 2025

Scanning-probe Single-electron Capacitance Spectroscopy
Published on: July 30, 2013
Direct Measurement of Negative Capacitance in Ferroelectric/Semiconductor Heterostructures
Lin Liu1, Lin Lei1, Xiaomei Lu1,2
1National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, China.
None:
Negative capacitance (NC) is now an attractive research topic owing to its potential applications. For better integration, investigation about the phenomenon and mechanism of NC in ferroelectric materials on semiconductor substrates is important. In this work, ferroelectric BaTiO3 (BTO) films are deposited on the low-resistance Si(100) substrates to constitute Pt/BTO/p-Si/Pt samples with the metal/ferroelectric/semiconductor/metal (MFSM) structure, on which NC are directly measured at low frequencies with a large DC bias. Because of the unique asymmetric interface, the NC value is tunable by the polarity and magnitude of the DC bias. Analysis based on the impedance and ferroelectric characteristics reveals that, in addition to the displacement current related to the electric polarization, there is also relaxation current caused by interface charge injection and oxygen vacancy migration. This work provides another idea for studying miniaturized and low-energy devices utilizing NC, which is of great significance for the development of silicon-based ferroelectric devices.
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