Monitoring nitrogen profiles in ultrathin gate dielectrics

This paper proposes an inexpensive, manufacturing friendly method of determining the nitrogen profile in ultrathin gate dielectrics to understand its dependence on process parameters. The method uses a variable etch across the wafer with a very dilute HF dip followed by rapid thermal oxidation, and utilizes the oxidation retarding capability of the incorporated nitrogen to draw important conclusions on the nitrogen profile across the thickness of the dielectric. This test can be used in statistical process control for monitoring the nitrogen profile in the dielectric. (C) 2002 The Electrochemical Society.