Electrical properties and reliability of MOSFET's with rapid thermal NO-nitrided SiO/sub 2/ gate dielectrics

Abstract

This paper reports on the performance and hot carrier reliability of N- and P-channel MOSFET's with oxynitride gate dielectrics fabricated by rapid thermal nitridation (RTN) of thermally grown SiO/sub 2/ in pure nitric oxide (NO) ambient. It is found that current drivability of N-channel MOSFET's increases with NO-nitridation of SiO/sub 2/. A significant enhancement in high field electron mobility is also observed with increasing NO-nitridation. P-channel MOSFET's with NO-nitrided SiO/sub 2/ gates show somewhat lower current drivability and hole mobility compared to SiO/sub 2/ for both low- and high-V/sub g/. Both N- and P-channel MOSFET's with NO-nitrided oxides show excellent immunity to channel hot carrier degradation. The improvement in hot-carrier reliability is attributed to the efficient incorporation of nitrogen in the dielectric through NO-nitridation. A 1000/spl deg/C, short 10-second NO-anneal was found to be the optimum nitridation condition since, compared to control oxide devices, these devices showed comparable electron and hole mobility but significantly enhanced hot-carrier immunity.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>