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On‐board vehicle applications dictate the need for improved low‐temperature power densities of rechargeable batteries. Integration of high‐permittivity artificial dielectric solid electrolyte interfaces (SEIs) into the lithium ion battery architecture is a promising path to satisfy this need. The relationship between the permittivity of various artificial dielectric SEIs and the resulting high‐rate capability at low temperatures is investigated. Room‐temperature studies reveal a weak relationship between these variables. However, at low temperatures, the correlation between the larger permittivity of the dielectric SEIs and the greater high‐rate capabilities of the cells is striking. The high‐rate capabilities for pulsed laser deposition‐synthesized cathode thin films with various BaTiO3 (BTO) SEIs covering configurations are evaluated. A remarkable improvement in the high‐rate capability is observed for LiCoO2 (LCO) modified with dot BTOs, while the rate capability for planar BTO (fully covered LCO) is weakened significantly. A series of experimental results prove that a large polarization, P, in the dielectric SEIs intensified with permittivity accelerates interfacial charge transfer near the dielectrics–LCO–electrolyte triple junction.

With wide application of low-dielectric constant (low-k) dielectric materials in multilevel VLSI circuits, the long-term reliability of such materials is rapidly becoming one of the most critical challenges for technology development. Among all the reliability issues, low4 time dependent dielectric breakdown (TDDB) is commonly considered a crucial problem. In this study, the effect of process variations on chemical-vapor deposited (CVD), carbon doped oxide dielectrics comprised of Si, C, 0, and H (SiCOH) TDDB degradation at the 65nm technology node is investigated. SiCOH TDDB is found to be sensitive to all aspects of integration.Based on extensive experimental data, an electrochemical-reactioninduced, three-step degradation model is proposed to explain the SiCOH dielectric breakdown process. Finally, we demonstrate that with careful process and materials optimization, a superior SiCOH TDDB performance at the 65nm technology node can be achieved for 300" fabrication. The projected lifetime, based on a conservative modeling approach and aggressive test structure is far beyond the most stringent reliability target. [

A series of the model complexes containing ortho-substituted arenethiolato ligands, ((Et4N)2[Fe4S4(S-2-RCONHC6H4)4] {R = Ph (1), 4-MeO–C6H4 (2), and 4-F–C6H4 (3)} and (Et4N)2[Fe4S4{S-2,6-(RCONH)2C6H3}4] {R = Ph (4), 4-MeO–C6H4 (5), and 4-F–C6H4 (6)}) was synthesized and characterized by 1H NMR, IR spectroscopy, and cyclic voltammetry. The solution structures of these complexes are discussed based on their 1H NMR T1 data and molecular-dynamics calculations. Complex 4 has a shorter distance (av. 4.3 Å) between the protons of the benzoyl group and the inorganic sulfur atom of the [4Fe-4S] cluster than the corresponding ones of 1 (av. 6.2 Å). These results indicate the C–H···S interaction between the protons of the benzoyl group and the sulfur atom of the [4Fe-4S] cluster. The [Fe4S4(SAr)4]2−/[Fe4S4(SAr)4]3−redox potential for 1 and 4 are −0.86 and −0.65 V, respectively. The difference between 1 and 4 is Δ0.21 V. This is larger than the value Δ0.11 V between [Fe4S4(S-2-t-BuCONHC6H4)4]2− (−0.91 V) and [Fe4S4{S-2,6-(t-BuCONH)2C6H3}4]2− (−0.80 V), considered to be the difference between singly and doubly NH··&middotS hydrogen-bonded complexes. The redox potentials for 1—6 follow the trend of the Hammett σm values, showing that the aromatic ring of the benzoyl group interacts with the [4Fe-4S] cluster directly. A cooperative effect between the C–H···S interaction and the NH···S hydrogen bond is thus found to regulate the redox potential of the model complexes.

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