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Oxygenases have been postulated to utilize d4FeIVand d8CuIIIoxidants in proton-coupled electron transfer (PCET) hydrocarbon oxidation. In order to explore the influence the metal ion and d-electron count can hold over the PCET reactivity, two metastable high-valent metal–oxygen adducts, [NiIII(OAc)(L)] (1b) and [CuIII(OAc)(L)] (2b), L = N,N′-(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamidate, were prepared from their low-valent precursors [NiII(OAc)(L)]−(1a) and [CuII(OAc)(L)]−(2a). The complexes 1a/b–2a/bwere characterized using nuclear magnetic resonance, Fourier transform infrared, electron paramagnetic resonance, X-ray diffraction, and absorption spectroscopies and mass spectrometry. Both complexes were capable of activating substrates through a concerted PCET mechanism (hydrogen atom transfer, HAT, or concerted proton and electron transfer, CPET). The reactivity of 1band 2btoward a series of para-substituted 2,6-di-tert-butylphenols (p-X-2,6-DTBP; X = OCH3, C(CH3)3, CH3, H, Br, CN, NO2) was studied, showing similar rates of reaction for both complexes. In the oxidation of xanthene, the d8CuIIIoxidant displayed a small increase in the rate constant compared to that of the d7NiIIIoxidant. The d8CuIIIoxidant was capable of oxidizing a large family of hydrocarbon substrates with bond dissociation enthalpy (BDEC–H) values up to 90 kcal/mol. It was previously observed that exchanging the ancillary anionic donor ligand in such complexes resulted in a 20-fold enhancement in the rate constant, an observation that is further enforced by comparison of 1band 2bto the literature precedents. In contrast, we observed only minor differences in the rate constants upon comparing 1bto 2b. It was thus concluded that in this case the metal ion has a minor impact, while the ancillary donor ligand yields more kinetic control over HAT/CPET oxidation.

Ge and III/V semiconductor substrates are recently being investigated as a candidate material for the replacement of Si substrates in advanced micro-electronic devices. The reintroduction of this material requires engineering of the standard IC processing steps. In this paper, we present how the trace analytical techniques of total reflection X-ray fluorescence spectrometry (TXRF) and atomic absorption spectrometry (AAS) contribute to the realization of suitable processes to realize a high quality gate stack on Ge and GaAs substrates. A conventional application for these techniques lays in contamination control on incoming wafers. Besides this, we demonstrate some more advanced applications such as the determination of dopant concentrations (As in Ge), the study of passivation processes (S on Ge) and the characterization of nanometer thin layers (Si on Ge, HfO2 on Si).

Passivation of the channel in the gate stack is the most important problem for introducing another material than silicon into the channel of CMOS devices. In order to compare the mobility values of different passivation techniques, we propose to use a parameter, which is a proportional to the drive current of the transistor. We call this parameter the channel mobility value and it is calculated from the transistor equation. This channel mobility value can be used to benchmark more consistently the different passivation techniques on germanium or other semiconductor materials. A second issue for CMOS scaling on Ge is the poor performance of nMOS devices and there seems no solution in sight for this problem. Therefore we promote the investigation of technologies to allow the introduction of III-V materials on Ge to make nMOS devices in III-V devices complementary with Ge pMOS. A third key issue is the development of a manufacturable and low defect density germanium-on-insulator (GeOI) technology on 200mm and larger substrate sizes.

Passivation of the channel in the gate stack is the most important problem for introducing another material than silicon into the channel of CMOS devices. In order to compare the mobility values of different passivation techniques, we propose to use a parameter, which is a proportional to the drive current of the transistor. We call this parameter the channel mobility value and it is calculated from the transistor equation. This channel mobility value can be used to benchmark more consistently the different passivation techniques on germanium or other semiconductor materials. A second issue for CMOS scaling on Ge is the poor performance of nMOS devices and there seems no solution in sight for this problem. Therefore we promote the investigation of technologies to allow the introduction of III-V materials on Ge to make nMOS devices in III-V devices complementary with Ge pMOS. A third key issue is the development of a manufacturable and low defect density germanium-on-insulator (GeOI) technology on 200mm and larger substrate sizes.

Ge and III/V semiconductor substrates are recently being investigated as a candidate material for the replacement of Si substrates in advanced micro-electronic devices. The reintroduction of this material requires engineering of the standard IC processing steps. In this paper, we present how the trace analytical techniques of total reflection X-ray fluorescence spectrometry (TXRF) and atomic absorption spectrometry (AAS) contribute to the realization of suitable processes to realize a high quality gate stack on Ge and GaAs substrates. A conventional application for these techniques lays in contamination control on incoming wafers. Besides this, we demonstrate some more advanced applications such as the determination of dopant concentrations (As in Ge), the study of passivation processes (S on Ge) and the characterization of nanometer thin layers (Si on Ge, HfO2on Si).