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We have clarified the impact on reliability of La incorporation into the HfSiON gate dielectrics nMOSFETs (PBTI, TDDB). Although La incorporation is effective for pre-existing defect suppression, stress induced defect generation is more sensitive to stress voltage and temperature. This is caused by the elevation of the energy level of oxygen vacancy and(More)
Effects of nitrogen incorporation on suppression of electron charge traps in Hf-based high- kappa gate dielectrics have been studied by first-principles calculations, focusing on interactions between N atoms and electrons trapped at oxygen vacancies (V<sub>O</sub>'s). Our total energy calculations revealed that the formation energy of a doubly occupied(More)
A novel technique for the control of nitrogen (N) and oxygen (O) concentrations in the metal/high-k gate stacks is proposed. By inserting a reactive metal (Ti) layer remote from work function metal and high-k insulator, N and O concentration is easily decreased. This technique effectively suppresses the EOT increase after high-temperature annealing.(More)
Charged defects in the gate insulating oxide cause various degradations in operating MOSFET such as flat-band voltage shifts or threshold voltage instabilities. Excess or deficient oxygen atoms in the oxide layer are relevant to those fixed charges, and thus oxygen concentration must be carefully controlled in the fabrication process. Given the fact that(More)
The N incorporation effect in Hf-based high-k gate dielectrics has been studied by the first-principles calculations. Interactions between N atoms and oxygen vacancies (Vos) in HfO/sub 2/ are investigated. Our calculations show that N atoms favorably occupy nearest neighbor oxygen sites to Vos. As a result, electron charge traps at Vos are remarkably(More)
Fermi-level pinning of poly-Si and metal-silicide gate materials on Hf-based gate dielectrics has been systematically studied theoretically. Fermi-level pinning in high-work-function materials is governed by the O vacancy generation and subsequent formation of interface dipoles near gate electrodes due to the electron transfer. On the other hand, O(More)
The authors have achieved a remarkably wide range (~1.2 V) of differences in flatband voltage (V<sub>fb</sub>) by using a combination of metal alloy (Pt-W)/La2O3 gate stacks. The controllable range is about 3 times greater than that of Hf-based gate stacks. The wide range of V <sub>fb</sub> can be maintained even after annealing in forming gas and oxidizing(More)
A combinatorial ternary composition spread method, which included continuous ternary and binary compositions, was applied for new materials exploration for the future gate stack structure, rapid estimation of permittivity are carried out by microwave microscope as well as conventional C-V measurement. Structural analyses are performed systematically by(More)
A combinatorial synthesis and high throughput characterization was employed to accelerate the new materials exploration. Also tow basic guide lines were shown to design the future nano CMOS. They are amorphous structure and defect control. As examples, we examined a HfO<sub>2</sub>-Y<sub>2</sub>O<sub>3</sub>-Al<sub>2</sub>O<sub>3</sub> ternary oxide for(More)
In this paper, we report multivariate analyses, such as principal component analysis and partial least-squares regression, of NMR spectra of poly(N-isopropylacrylamide)s [poly(NIPAAm)s]. Principal component analysis successfully interpreted the assignments of NMR spectra of poly(NIPAAm)s in terms of stereostructures for the methine carbons at triad levels(More)