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We have investigated RIE-induced damage in MOS devices with thermal oxide as well as [N.sub.2]O-annealed oxide as gate dielectrics. A systematic improvement in robustness against RIE-induced damage is seen when [N.sub.2]O flow rate and/or [N.sub.2]O anneal temperature are increased. We have demonstrated a [N.sub.2]O anneal process at 900 [degrees] C, which provides a robust Si[O.sub.2]/Si interface against plasma damage and hot carrier stress.

Analysis of the effects of AC hot carrier stress on n- and p-MOSFETs with NH3-nitrided (RTN) and reoxidized nitrided (RTN/RTO) gate oxides reveals an increase in degradation of n-MOSFET and suppressed degradation of P-MOSFET independent of the gate dielectric employed. RTN/RTO gate oxides suppress degradation of n-MOSFETs and increase degradation of p-MOSFETs under AC stress. The degradation depends on frequency and gate pulse duty cycle.

Various surface pretreatments of polysilicon electrodes prior to Si3N4 dielectric film deposition were studied. Rapid thermal NH3-nitridation lowered leakage current, decreased charge trapping and exhibited superior time-dependent dielectric breakdown characteristics when compared to rapid thermal H2-Ar clean.

The impact of post-gate processing on the metal oxide semiconductor (MOS) capacitors and MOS field effect transistors properties is investigated. A degradation is shown to occur in MOS devices subjected to source-drain annealing and borophosphosilicate-glass densification and reflow in an N2 ambient with O2 of varying concentrations. Such a degradation in the low-field breakdown characteristics transpires during electron injection at the polycrystalline silicon/SiO2 junction.

The thickness and electrical characteristics of ultrathin dielectric films grown on silicon wafers in a pure N2O ambient were investigated. The results showed that the N2Ooxides had interface state densities and breakdown fields similar to that observed in oxides grown in pure O2. However, interface state generation and charge trapping were much smaller in the N2O oxides than in those grown in pureO2.

An in situ rapid thermal chemical vapor deposition process has achieved the achievement of high quality HfO2 gate stack with equivalent oxide thickness of 7.8-angstrom unit. The HfO2 gate stacks show negligible frequency dependence, small hysteresis in capacitance-voltage and weak temperature dependence of the leakage current.

A new model involving kinetic reactions between inactive boron-silicon interstitially and electrically stimulated boron species characterizes the suppressed dopant-activation in BF2- and boron-implanted silicon. Ion incorporation generates self-interstitial supersaturation that lowers boron activation in the silicon during rapid thermal annealing. The model separates the total boron concentration and active boron concentration.

The investigation of radiation hardness of furnace N2O nitrided gate oxides for n- and p-channel MOSFET's is effected by the exposure of the devices in X-ray radiation systems. A decrease in channel length with an increased degradation is found in the control N2O nitrided MOSFET's. An increased radiation hardness against the accumulation of positive charges and generation of interface state is found in the N2O nitrided MOSFET.

Time-dependent breakdown of oxynitride gate dielectrics under unipolar ac stress was investigated. The results showed that the gate dielectrics featured a longer time-to-breakdown under ac stress compared to constant voltage stress. However, different types of dielectrics exhibited different detrapping behavior and improvement factors for breakdown under ac stress.

A study was done on the photoluminescence (PL) of porous Si which has been hydrogenated in boiling water. It was shown that PL intensity increases and spectral peak shifts to shorter wavelength with increasing boiling time. The shift of the spectrum to quantum size effects was found to be due to the reduction of the size of the confinement produced by oxidation. Rehydrogenation by boiling restores the increase in intensity of PL.