The observation of trapping and detrapping effects in high-k gate dielectric MOSFETs by a new gate current Random Telegraph Noise (IG-RTN) approach

Abstract

A new method, called gate current Random Telegraph Noise (I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</inf> RTN), was developed to analyze the oxide quality and reliability of high-k gate dielectric MOSFETs. First, a single electron trapping/detrapping from process induced trap in nMOSFET was observed and the associated physical mechanism was proposed. Secondly, I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</inf> RTN has also been successfully applied to differentiate the difference in electron tunneling mechanism for a device under high-field or low-field stress. Finally, the soft-breakdown (SBD) behavior of a device can be clearly identified. Its I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</inf> RTN characteristic is different from that before soft-breakdown. It was found that SBD will indeed induce extra leakage current as a result of an additional breakdown path.