Electron paramagnetic resonance ͑EPR͒ measurements of Si/SiO 2 systems began over 30 years ago. Most EPR studies of Si/SiO 2 systems have dealt with two families of defects: P b centers and EЈ centers. Several variants from each group have been observed in a wide range of Si/SiO 2 samples. Some of the most basic aspects of this extensive, body of work remain controversial. EPR is an extraordinary powerful analytical tool quite widely utilized in chemistry, biomedical research, and solid state physics. Although uniquely well suited for metal-oxide-silicon ͑MOS͒ device studies, its capabilities are not widely understood in the MOS research and development community. The impact of EPR has been limited in the MOS community by a failure of EPR spectroscopists to effectively communicate with other engineers and scientists in the MOS community. In this article we hope to, first of all, ameliorate the communications problem by providing a brief but quantitative introduction to those aspects of EPR which are most relevant to MOS systems. We review, critically, those aspects of the MOS/EPR literature which are most relevant to MOS technology and show how this information can be used to develop physically based reliability models. Finally, we briefly review EPR work dealing with impurity defects in oxide thin films.

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Effectively controlling quantum mechanical tunneling through an ultrathin dielectric represents a fundamental materials challenge in the quest for high-performance metal-insulatormetal (MIM) diodes. Such diodes are the basis for alternative approaches to conventional thin-fi lm transistor technologies for large-area information displays, [ 1 , 2 ] various types of hot electron transistors, [2][3][4][5][6] ultrahigh speed discrete or antennacoupled detectors, [7][8][9][10][11][12][13][14] and optical rectennas. [ 15 ] MIM diodes have been fabricated by anodization, [ 1 ] thermal oxidation, [ 8-11 , 14 ] plasma oxidation, [ 10 , 12 , 13 ] or plasma nitridation [ 16 ] of crystalline metal fi lms. Diodes fabricated using these approaches have invariably exhibited poor yield and performance. These problems are to a large extent a consequence of the roughness of the surface of the crystalline metal fi lm, which is often larger than the thickness of the MIM insulator. As a result, the electric fi eld across a MIM device will be highly nonuniform, making the control of quantum mechanical tunneling problematic. In this contribution, we describe the use of an amorphous metal contact as a critical component for circumventing the surface roughness and fi eld uniformity roadblocks that have precluded the realization and utility of MIM electronics for applications requiring high device current rectifi cation ratios (e.g. display applications).The MIM diode is the fundamental building block of metalinsulator electronics. The device is characterized by a high degree of nonlinearity in its current-voltage characteristics as a result of a large difference in conductivity between on and off states. The operational theory of this diode, based on Fowler-Nordheim tunneling, has been described in detail by Simmons. [ 17 , 18 ] The probability of quantum mechanical tunneling depends exponentially on the thickness of the insulator between a pair of metal electrodes. Hence, the performance of the diode is critically dependent on the thickness uniformity of the tunnel-dielectric layer across the entire device. Interfacial roughness and dielectric imperfections give rise to alternate conduction mechanisms, e.g. Frenkel Poole emission, that can dominate at low voltages and reduce the device rectifi cation ratio. The inability to create and effectively control a uniform electric fi eld across the whole device area has been the primary limitation in producing reliable MIM devices. Here, we demonstrate that the necessary fi eld control can readily be achieved by integrating the atomically smooth-surface of an amorphous metal electrode with high-quality insulators. This combination provides a rich materials and processing palette for development of MIM electronics, enabling new strategies for device design and fabrication.Amorphous metals have been primarily investigated as bulk materials, addressing diverse applications that range from micromachines and hinges for digital light processors to golf clubs and transformer cores. [19][20][21] T...

We report here on applying electric fields and dielectric media to achieve controlled alignment of single-crystal nickel silicide nanowires between two electrodes. Depending on the concentration of nanowire suspension and the distribution of electrical field, various configurations of nanowire interconnects, such as single, chained, and branched nanowires were aligned between the electrodes. Several alignment mechanisms, including the induced charge layer on the electrode surface, nanowire dipole-dipole interactions, and an enhanced local electrical field surrounding the aligned nanowires are proposed to explain these novel dielectrophoretic phenomena of one-dimensional nanostructures. This study demonstrates the promising potential of dielectrophoresis for constructing nanoscale interconnects using metallic nanowires as building blocks.

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We demonstrate selective growth of vertically aligned ZnO nanowires on a (100) Si substrate using a patterned thin film ZnO seed layer. Metal catalysts, which can be a source of contamination, were not used. A single-crystalline structure with c-axis preferred orientation and a strong intrinsic near band edge photoluminescence peak at 380 nm with no detectable visible photoluminescence indicate a lack of defects and the high quality of the ZnO nanowires.

Low temperature atomic layer deposition (ALD) of monolayer to few layer MoS 2 uniformly across 150 mm diameter SiO 2 /Si and quartz substrates is demonstrated. Purge separated cycles of MoCl 5 and H 2 S precursors are used at reactor temperatures of up to 475 C. Raman scattering studies show clearly the in-plane (E 1 2g) and out-of-plane (A 1g) modes of MoS 2. The separation of the E 1 2g and A 1g peaks is a function of the number of ALD cycles, shifting closer together with fewer layers. Xray photoelectron spectroscopy indicates that stoichiometry is improved by postdeposition annealing in a sulfur ambient. High resolution transmission electron microscopy confirms the atomic spacing of monolayer MoS 2 thin films. V

Multiwalled carbon nanotubes ͑CNTs͒ were coated, using atomic layer deposition, with a thin layer of ZnO and subsequently annealed. Studies of the morphologies of the ZnO-coated CNTs revealed no significant change in the internal structures ͑multiwalled graphite sheets͒ and the diameters of the CNTs, but the ZnO appeared to form bead-shaped single crystalline particles attaching to the surface of the nanotubes. The electron field-emission properties of the ZnO-coated CNTs were dramatically improved over both uncoated CNTs and ZnO nanowires. It is reasoned that numerous ZnO "nanobeads" on the surface of the nanotubes serve as additional emission sites, in addition to the tips of CNTs, and result in the enhancement of electron field emission.