Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Many materials systems are currently under consideration as potential replacements for SiO2 as the gate dielectric material for sub-0.1 μm complementary metal–oxide–semiconductor (CMOS) technology. A systematic consideration of the required properties of gate dielectrics indicates that the key guidelines for selecting an alternative gate dielectric are (a) permittivity, band gap, and band alignment to silicon, (b) thermodynamic stability, (c) film morphology, (d) interface quality, (e) compatibility with the current or expected materials to be used in processing for CMOS devices, (f) process compatibility, and (g) reliability. Many dielectrics appear favorable in some of these areas, but very few materials are promising with respect to all of these guidelines. A review of current work and literature in the area of alternate gate dielectrics is given. Based on reported results and fundamental considerations, the pseudobinary materials systems offer large flexibility and show the most promise toward success...

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High-κ gate dielectrics: Current status and materials properties considerations

Phase-change materials are some of the most promising materials for data-storage applications. They are already used in rewriteable optical data storage and offer great potential as an emerging non-volatile electronic memory. This review looks at the unique property combination that characterizes phase-change materials. The crystalline state often shows an octahedral-like atomic arrangement, frequently accompanied by pronounced lattice distortions and huge vacancy concentrations. This can be attributed to the chemical bonding in phase-change alloys, which is promoted by p-orbitals. From this insight, phase-change alloys with desired properties can be designed. This is demonstrated for the optical properties of phase-change alloys, in particular the contrast between the amorphous and crystalline states. The origin of the fast crystallization kinetics is also discussed.

Phase-change materials for rewriteable data storage

At interfaces between complex oxides, electronic systems with unusual electronic properties can be generated. We report on superconductivity in the electron gas formed at the interface between two insulating dielectric perovskite oxides, LaAlO3 and SrTiO3. The behavior of the electron gas is that of a two-dimensional superconductor, confined to a thin sheet at the interface. The superconducting transition temperature of ≅ 200 millikelvin provides a strict upper limit to the thickness of the superconducting layer of ≅ 10 nanometers.

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Superconducting Interfaces Between Insulating Oxides

Raman spectroscopy is a standard characterization technique for any carbon system. Here we review the Raman spectra of amorphous, nanostructured, diamond-like carbon and nanodiamond. We show how to use resonant Raman spectroscopy to determine structure and composition of carbon films with and without nitrogen. The measured spectra change with varying excitation energy. By visible and ultraviolet excitation measurements, the G peak dispersion can be derived and correlated with key parameters, such as density, sp(3) content, elastic constants and chemical composition. We then discuss the assignment of the peaks at 1150 and 1480 cm(-1) often observed in nanodiamond. We review the resonant Raman, isotope substitution and annealing experiments, which lead to the assignment of these peaks to trans-polyacetylene.

Raman spectroscopy of amorphous, nanostructured, diamond-like carbon, and nanodiamond

Chemical bonding and electronic structure of high-κ transition metal dielectrics: applications to interfacial band offset energies and electronically active defects

Constant current stress (CCS) has been used to investigate the Stress-Induced Leakage Current (SILC) to clarify the influence of boron penetration and nitrogen incorporation on the breakdown of p-channel devices with sub-2.0 nm Oxide/Nitride (O/N) and oxynitride dielectrics prepared by remote plasma enhanced CVD (RPECVD). Degradation of MOSFET characteristics correlated with soft breakdown (SBD) and hard breakdown (HBD), and attributed to the increased gate leakage current are studied. Gate voltages were gradually decreased during SBD, and a continuous increase in SILC at low gate voltages between each stress interval, is shown to be due to the generation of positive traps which are enhanced by boron penetration. Compared to thermal oxides, stacked O/N and oxynitride dielectrics with interface nitridation show reduced SILC due to the suppression of boron penetration and associated positive trap generation. Devices stressed under substrate injection show harder breakdown and more severe degradation, implying a greater amount of the stress-induced defects at SiO2/substrate interface. Stacked O/N and oxynitride devices also show less degradation in electrical performance compared to thermal oxide devices due to an improved Si/SiO2 interface, and reduced gate-to-drain overlap region.

Degradation and SILC Effects of RPECVD sub-2.0nm Oxide/Nitride and Oxynitride Dielectrics Under Constant Current Stress

Three inter-related topics are addressed: (i) ray spectroscopy (XAS) studies of remote plasma deposited (RPD) nc-SiO2 and nc-GeO2 emphasizing (a) band-edge states and (b) pre-existing bonding defects: (ii) interpretation of X-ray absorption and photoemission spectra based on many electron theory, and (iii) band-edge electronic structure and intrinsic defects in nc-SiO2 and nc-GeO2 thin films and their respective interfaces with Si and Ge substrates. The most significant result is the identification of local atomic structure and medium range order (MRO) cluster in which pre-existing defects are embedded. The defects are vacated O-atom sites in which O-atoms have never been resident. They are confined to 1 nm scale chemically-ordered clusters distributed aperiodically in quartz-structured 4-fold coordinated Si(Ge) and 2-fold coordinated O clusters comprised of 12-atom Si–O and Ge–O regular rings. The vacated site defects are formed during processing and annealing, reducing macroscopic strain. Finally, they are qualitatively different, and therefore readily distinguished from defects introduced by electrical stressing, and by X-ray, γ-ray or high energy electron stressing.

Band-edge electronic structures, and pre-existing defects in remote plasma deposited (RPD) non-crystalline (nc-) SiO2 and GeO2

Annealing of “intrinsic” and photo-induced defects in hydrogenated amorphous silicon

Low-Thermal-Budget Process-Controlled Monolayer Level Incorporation of Nitrogen into Ultra-Thin Gate Dielectric Structures: Applications to MOS Devices

Gerald Lucovsky

Papers

Chemical bonding and electronic structure of high-κ transition metal dielectrics: applications to interfacial band offset energies and electronically active defects

Degradation and SILC Effects of RPECVD sub-2.0nm Oxide/Nitride and Oxynitride Dielectrics Under Constant Current Stress

Band-edge electronic structures, and pre-existing defects in remote plasma deposited (RPD) non-crystalline (nc-) SiO2 and GeO2

Annealing of “intrinsic” and photo-induced defects in hydrogenated amorphous silicon

Low-Thermal-Budget Process-Controlled Monolayer Level Incorporation of Nitrogen into Ultra-Thin Gate Dielectric Structures: Applications to MOS Devices