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Hydrogenated carbon nitride films with which elastic recovery are prepared by dual dc-rf plasma enhanced chemical vapor deposition. It is found that hydrogen atoms are mainly incorporated to s[p.sup.3] carbon atoms and reduce the dimension of cross-linking 3D network in C[N.sub.x]:H films.

The paper presents the design and first test results of the high-speed Beam Conditions Monitor (BCM) for the ATLAS Experiment at the Large-Hadron Collider (LHC). The goal of the BCM is to monitor instantaneous rates of collision and background and detect signs of beam instabilities. The detector is based on polycrystalline Chemical-Vapor-Deposition (pCVD) diamond as active sensor material. We have chosen this detector material for its proven radiation hardness and fast signal properties. For the readout of the diamonds we developed front-end readout electronics based on high-bandwidth RF amplifiers. The signal response of the amplifier has been optimized for the ionization current signal of pCVD diamond in order to achieve a signal rise time of [less than or equal to] 1 ns and pulsewidth of less than 3 ns. We present test results which were obtained on prototype assemblies in source tests and testbeam. The obtained results demonstrate the feasibility of such a detector system for the ATLAS BCM. The tests yield BCM signals with a mean rise time of 900 ps and a FWHM pulsewidth of 2.1 ns after 16 m of required transmission cable. The recorded signal amplitude distribution yields an most probable signal-to-noise ratio of 8.6:1 for single minimum-ionizing particles (MIP). Index Terms--Beam diagnostic, diamond, high-speed electronics, Large-Hadron Collider (LHC), proton detectors, semiconductor radiation detectors.

The use of impedance spectroscopy that can isolate the differing components that contribute to the overall conductivity of high-quality chemical-vapor deposition (CVD) diamond thin films is reported. The results suggest the presence of two conduction paths with activation energies of 0.53 and 0.197 eV.

The internal stresses of different diamond and diamondlike carbon (DLC) coatings are evaluated. Higher compressive residual stresses in the DLC films are noticed that are also related to their chemical bonding nature as well as their microstructures.

Diamond-silicon carbide composites were formed from diamond powder and liquid silicon at high pressure-high temperature conditions. X-ray diffractograms of the specimens formed for different time periods provided information on the SiC formation rate and activation energy.

The thermal stability between exposed diamondlike carbon and buried diamondlike carbon films is compared to investigate the cause of the high thermal stability of the buried diamondlike carbon layer in silicon on diamond. Both Raman spectroscopy and x-ray photoelectron spectroscopy results disclose that the buried diamondlike carbon film has a higher thermal stability due to a slower graphitization process compared with the exposed diamondlike carbon film.

A technique for patterning diamond nanogrit, which utilizes commercial ink-jet printer technology is presented. This technique is used to demonstrate a quick and simple means to seed patterned, nanocrystalline diamond films onto candidate substrates.

The scanning tunneling microscopic (STM) technique was used to examine the electron field emission properties of the nanodiamond films. The results clearly suggested that the presence of impurity states due to boron doping is a prime factor improving the field emission properties for the boron-doped nanodiamond films.

Results of electrical and structural properties of type IIa diamonds implanted with phosphorous, sulfur and argon ions following a variety of annealing/implantation schemes are presented. It is concluded that a sulfur defect related complex, which decomposes at T>800degree Celsius is responsible for the electrical effects in sulfur implanted diamond.

The electrical properties of some representative diamond-based films produced by inserting Nd, Ti and W as foreign species are investigated. The results obtained form Hall effect and conductivity measurements are related to the structural and compositional characteristics of these materials.

The variation of strain, sp(sup 2) hybridized carbon combination and defect density through the thickness by micro-Raman scattering and microphotoluninescence spectroscopy is evaluated. The results are correlated with curvature observations on detached films, which reflect through thickness strain gradients in the films.

Low-energy electrons were transmitted through two chemical-vapor-deposited (CVD) diamond films having similar B concentrations but different thickness. It was found that the transmitted energy distributions were very similar from the two samples in spite of the substantial difference in film thickness.

A methodology has been developed for studying deep levels in defect semiconductor crystals with a high degree of accuracy, even when a large number of close deep levels are present in the sample and their sample and their spectral contributions overlap. The proposed method has been adopted to study neutron irradiated silicon detectors and unirradiated chemical vapor deposited (CVD) diamond films giving satisfactory results in both the cases.

The influence of annealing and microwave (MW) hydrogen plasma exposure of ion-beam-irradiated diamond film surfaces is investigated. The analysis shows that the longer exposure to MW hydrogen plasma completely removes defects and results in a high yield of secondary electron emission (SEE).

Diamond-like carbon films were deposited using the electron cyclotron resonance chemical vapor deposition (ECR-CVD) system. A model for the ECR plasma was formulated and reveals information about the ECR-CVD plasma under different deposition conditions.

Field electron emission of nanocrystalline diamond films with controllable grain size and graphite content, grown by microwave plasma-assisted chemical vapor deposition using N2/CH4/H2 as precursors is studied. When the microstructure of the films is uniform enough, the micro-scale switching behavior can even be amplified to macroscale.