Dawei Heh

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After over 10 years of intensive study on high-k dielectric and metal gate electrode to replace silicon based materials (Si02 or SiON gate dielectric and polysilicon gate) in the complementary-metal-oxide-semiconductor (CMOS) application, it was claimed that hafnium based dielectric and metal gate are finally ready to be implemented in 45nm technology and(More)
A single pulse technique with a wide range of pulse times has been applied to study trap charging and discharging mechanisms in nMOSFET high-k devices. It is shown that both charging and discharging are controlled by two distinctive processes with different characteristic times. A proposed characterization methodology, which separates the relaxation effects(More)
Band engineering in TANOS (TaN-Al<sub>2</sub>O<sub>3</sub>-Si<sub>3</sub>N<sub>4</sub>-SiO<sub>2</sub>-Silicon) Flash memory utilizing an interfacial dipole is demonstrated for the first time. A dipole layer at the tunnel oxide/charge storage layer interface leads to increase in programming speed while maintaining good retention and endurance. Using a(More)
We demonstrate for the first time a gate first high-k/metal gate (MG) nFET with EOT = 0.74 nm (T<sub>inv</sub> = 1.15 nm), low V<sub>t</sub> = 0.30 V, high performance [I<sub>on</sub>/I<sub>Off</sub> = 1310(muA/um) at 100(nA/um)], low leakage (&gt; 200x reduction vs. SiO<sub>2</sub>/PolySi) and good PBTI. Low-k interface layer scaling and high-k La-doping(More)
High-k gate stack reliability has become one of the critical factors impacting the introduction of advanced gate stacks in future technology nodes. A high density of as-grown electron traps in the transition metal oxides (Bersuker et al., 2004) and the presence of the SiO<sub>2</sub> layer at the interface between the high-k dielectric and the substrate,(More)
Threshold voltage (VT) instability behavior in high-k devices was investigated using conventional DC, pulse, and "on-the-fly" bias temperature instability (BTI) measurements. By comparing the results, the effect of fast transient charging and relaxation on BTI has been evaluated
Constant voltage stress (CVS) combined with charge pumping (CP) measurements was applied to study trap generation phenomena in SiO<sub>2 </sub>/HfO<sub>2</sub>/TiN stacks. Using the analysis for frequency-dependent CP data developed to address depth profiling of the electron traps, we have determined that the voltage stress-induced generation of the defects(More)
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