For the first time, we perform a systematic investigation of the fast and slow components of dynamic NBTI (DNBTI)in p-MOSFET with SiON gate dielectric. The new findings are: (1)The recent debate in the slow DNBTI component measured by conventional DC method [1-5] is clarified. We show evidence that the slow DNBTI is due to interface traps N it generation and passivation. The conventional methods used over the past years seriously underestimate N it due to passivation of N it during measurement. (2) The fast DNBTI component measured by the fast method [7] is due to trapping and de-trapping of hole traps N ot in SiON. The accumulative degradation increases with increasing stress frequency. Model simulations are in excellent agreement with all experiments. (3)We re-evaluate the impact of DNBTI on device lifetime and circuit applications in the light of this new finding. Introduction: DNBTI is a critical reliability issue for CMOS transistors with silicon oxynitride SiON gate dielectric [1-6].Using the fast measurement method developed in [7], the DNBTI degradation in ultra-thin SiON gate dielectrics is re-investigated. Device fabrication and measurement: Devices were fabricated using 0.11 �m CMOS technology. The gate oxides with EOT of 1.3nm were grown by thermal oxidation followed by decoupled plasma nitridation and post-deposition thermal annealing. The fast V th measurement method [7] is illustrated in Fig.1. Pulses are inserted in gate stress and I d -V g is measured at falling or rising edge of the pulse (Fig. 1 inset). Fig.2 shows that 50us measurement time is fast enough. Interface trap density is measured by an improved DCIV method [1]. What DC and fast methods measure in DNBTI: Fig.3 shows the DNBTI [1,7] response of a p-FET, measured by conventional DC and fast methods respectively. DC method :Figs.4-6 clearly demonstrate that the slow components in the DNBTI measured by the DC method is mainly due to generation and passivation of the interface traps N it [1-4], and not due to trapping and detrapping in SiON hole traps N ot as proposed in [5]. Figs.4,5 show that the transient result depends on the order of measurements of N it and V th , indicating both measured N it and �V th are underestimated due to passivation of N it during measurement. Fig.6 demonstrates the misleading interpretation by [5] in the passivation phase due to the wrong curve alignment. Fast method: In Fig.8, using the pulse falling and rising edges to measure points S f and P in Fig.3, the transient amplitude can be measured. In Fig.9, rising edge measures the accumulative degradation under DNBTI. Figs.10-12 show the static and dynamic NBTI measured by fast and DC methods respectively, showing different time, V g and temperature dependences. The slope of time dependence of the fast method result is much smaller than the value of 0.25 anticipated in interface trap diffusion-reaction model [2]. Actually the fast NBTI component, defined as the difference between �V th measured by fast and slow method, can be interpreted by trapping and de...

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We have utilized resonant Raman scattering to investigate the phonon modes of self-organized Ge quantum dots grown by molecular-beam epitaxy. Both Ge-Ge and Si-Ge phonon modes are found to exhibit strong enhancements at the E 1 exciton. The strain in the quantum dots deduced from the phonon energies is consistent with the results of high-resolution transmission electron microscopy. An upper bound on the confinement energy of the E 1 exciton in quantum dots was deduced. The enhancement strength in the Si-Ge phonon indicates strong interaction between this mode and the E 1 exciton of the Ge dots. ͓S0163-1829͑99͒12403-2͔