The atomistic effects of N atoms on the leakage current through HfO2 high-k gate dielectrics have been studied from first-principles calculations within the framework of a generalized gradient approximation (GGA). It has been found that the intrinsic effects of N atoms drastically reduce the electron leakage current. N atoms couple favorably with oxygen vacancies (VO) in HfO2 and extract electrons from VO. As a result, VO energy levels are drastically elevated due to the charged-state change in VO from neutral (VO0) to positively charged (VO2+). Accordingly, N incorporation removes the electron leakage path mediated by VO related gap states.

It is widely believed that existing electroweak data requires a Standard Model Higgs to be light while electroweak and flavour physics constraints require other scalars charged under the Standard Model gauge couplings to be heavy. We analyze the robustness of these beliefs within a general scalar sector and find both to be incorrect, provided that the scalar sector approximately preserves custodial symmetry and minimal flavour violation (MFV). We demonstrate this by considering the phenomenology of the Standard Model supplemented by a scalar having SU c (3) × SU L (2) × U Y (1) quantum numbers (8, 2) 1/2which has been argued [13] to be the only kind of exotic scalar allowed by MFV that couples to quarks. We examine constraints coming from electroweak precision data, direct production from LEPII and the Tevatron, and from flavour physics, and find that the observations allow both the Standard Model Higgs and the new scalars to be simultaneously light -with masses ∼ 100 GeV, and in some cases lighter. The discovery of such light coloured scalars could be a compelling possibility for early LHC runs, due to their large production cross section, σ ∼ 100 pb. But the observations equally allow all the scalars to be heavy (including the Higgs), with masses ∼ 1 TeV, with the presence of the new scalars removing the light-Higgs preference that normally emerges from fits to the electroweak precision data.

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The microscopic mechanism of the degradation occurring in HQ-based high-ML dual layer gate insulator bas been investigated. The hole-injection-induced release of hydrogen from Si-H terminations causes IL-breakdown. This mechanism accelerates NBTI. Defects due to electron-trapped oxygen vacancies are the origin of trap-assisted tunneling, causing SILC in the electron current and PBTI.