RELIABILITY OF NITRIDED SI-SIO2 INTERFACES FORMED BY A NEW, LOW-TEMPERATURE, REMOTE-PLASMA PROCESS

Controlled amounts of nitrogen atoms have been incorporated at Si-SiO2 interfaces by a new, low-temperature (300 degrees C), remote-plasma p rocess, and corresponding improvements in device reliability are repor ted. Interfacial nitrogen-atom concentrations, up to 1X10(15) cm(-2), were obtained by a predeposition, remote plasma-assisted oxidation usi ng mixtures of N2O and O-2. Auger electron spectroscopy and secondary ion mass spectrometry studies to analyze N-atom concentrations at Si-S iO2 interfaces are discussed. Also, the results of electrical testing of submicron, n-channel metal-oxide-silicon field-effect transistors f abricated with this new process technology are reported. We found that the incorporation of N atoms at the Si-SiO2 interface increased curre nt drive capability at high gate voltages but did not affect the thres hold voltage of devices or the peak channel transconductance, g(m). De vice reliability, as measured by resistance to peak g(m) degradation a fter hot-carrier stressing, was found to increase with increasing N-at om concentrations at the Si-SiO2 interface. (C) 1995 American Vacuum S ociety.