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The authors implanted P atoms at 50 and 140-keV energies with respective fluences of 1 × 10 14 and 2 × 10 14 /cm 2 into diamond thin films synthesized by chemical vapor deposition on the type-Ib diamond substrate formed by high-pressure and high-temperature conditions. The occupational sites of implanted P atoms were determined in each processing stage of P implantation, ion-beam-induced epitaxial crystallization (IBIEC) annealing by 3-MeV-Ne 2 + ion irradiation at 750 ° C, and thermal annealing at 850 ° C in vacuum, by quantitatively comparing the random and channeling yields in Rutherford backscattering (RBS) measurements. In the analysis of RBS spectra, simulated distributions were fitted to the experimentally obtained spectra and we quantitatively identified the occupational sites and ratio of implanted P atoms. In addition, we investigated the diffusion phenomenon of implanted P atoms during annealing processes from the depth profile of scattered He ions. Consequently, the averaged occupational ratio in the substitutional lattice site was stably recorded around 50%. From the depth profile in the RBS spectra, thermal diffusion of implanted P atoms was clearly observed during the last thermal annealing after MeV-IBIEC annealing. We finally discuss the potentials of the MeV-IBIEC irradiation at relatively low temperatures applying to useful and credible annealing methods for electrical activation as well as recovery of damaged crystallinity. [ABSTRACT FROM AUTHOR]

Effective impurity doping into diamond by an ion implantation technique has been one of the crucial issues for realizing diamond-based high-power electronic devices. Especially for n-type impurity doping, the electrical activation has not been accomplished yet in a practically available level. In this study, local structures and depth profiles of implanted phosphorus atoms were studied by x-ray absorption spectroscopy, secondary ion mass spectroscopy, and first-principles calculations. P ion implantations were performed at two extreme substrate temperatures of room temperature and 900 ° C at multiple incident energies from 10 to 150 keV for flat doping and a single energy of 200 keV for δ -doping followed by activation annealing at 1300 ° C. The x-ray absorption spectra and the theoretical calculation showed that most of the implanted phosphorus atoms implanted with a flat doping concentration are existent in the substitutional site; however, they seem to bond with hydroxyl or vacancy complexes, probably resulting in electrical inactivation. Indeed, secondary ion mass analysis showed that a large number of O and H atoms are distributed in the P-doped layer, probably diffused from the surface through a damaged network. On the other hand, impurity diffusion was not observed in the P δ -doped sample followed by high-temperature annealing with a cap layer. It is clearly suggested that a damaged layer by ion irradiation near the surface acts as diffusion channels and trap sites of various impurities. High-temperature annealing with a cap layer is also quite effective in suppressing the formation of the defective layer that becomes a diffusion path of O and H. [ABSTRACT FROM AUTHOR]

We homoepitaxially synthesized a pure diamond film on type Ib base substrates by microwave plasma-assisted special chemical vapor deposition method and then doped B impurity atoms by the ion implantation technique with various doping concentrations from 2 × 10 17 to 2 × 10 19 cm − 3 at room temperature followed by activation annealing at 1300 ° C. The electrical properties of specific resistance, carrier concentration, Hall mobility, and conductive carrier type were analyzed by Hall effect measurements based on the van der Pauw method at sample temperatures from 77 to 873 K. We consequently realized excellent B-doping in the CVD-synthesized diamond film with a low compensation ratio and perfect doping efficiency and confirmed p -type conduction at almost all temperature ranges for the measured samples. In very lightly doped diamond, we observed first the existence of deep acceptor levels located near 1.85 eV with respect to the valence band maximum and proposed a conduction mechanism based on hopping conduction in deep acceptor levels. We showed the availability of this doping process to high-efficient B doping with various acceptor concentrations in diamond. The great success achieved in the activation of acceptor B implanted in diamond with various doping concentrations should definitely contribute to the progress in the application of diamond-based power semiconductor devices. [ABSTRACT FROM AUTHOR]

We study morphological changes on the Si surface induced by the C60 ion beam under various irradiation conditions. The fluence and incident energy of the C60 ion beam was 1 × 1016–1 × 1019 ions/m2 and 50 keV–9 MeV, respectively. The beam's incident angle to the surface normal was 0° or 60°. As a result of the changes in these variables, three types of nanostructures were observed: concave and convex, stringlike, and ripple structures. Structure shapes or sizes varied with changes in the parameters. Almost all cases showed concave and convex structures at an incident angle of 0°. At a 60° incident angle, stringlike or ripple structures were formed. Stringlike structures were formed at higher incident energy, while ripple structures were formed at lower incident energy. We found that both stringlike and ripple structures can form from sputtering and thermal effects. The formation of string structure requires a thicker amorphous layer and the proper balance of sputtering and annealing. [ABSTRACT FROM AUTHOR]

The stability of a corona discharge is important in electrophotography and other applications. Siloxane is known to influence corona discharge stability. In this paper, the voltage for maintaining a constant corona discharge current in an atmosphere containing siloxane vapor is monitored as a function of time. During the period when siloxane vapor is being sent to a corona discharge area, an increase of the voltage is observed, and a decrease of the voltage is observed just after stopping siloxane vapor containment. Based on this voltage increase and decrease, the main mechanisms of the voltage change are considered as wire degradation and discharge restraint by the siloxane vapor itself in the corona discharge area. Index Terms--Applied voltage, corona discharge, film, growth, needles, silicone oxide, siloxane.

Printed images of food products appearing on packaging usually include vivid colors in order to draw the attention of customers and influence their buying decisions on the product. Buying decisions on Durio zibethinus L. or Durian cv. Monthong are not instantaneous. Packaging designers and marketers need to understand how color stimuli impact the customer's buying decision process. The color attributes of durian images, such as hue, saturation, and intensity based on HSI color system were evaluated for examining the color and generating stimuli. A psychophysical experiment was conducted based on the feelings of "deliciousness," "attractiveness," and "naturalness" from the packaging, as these feelings impact buying decisions. Multivariate analysis of variance (MANOVA) indicated that saturation had a significant effect on all the feelings that influence buying decisions. The multiple regression analysis showed that the relationships between "Attractiveness of Flesh (Att‐F)" and "Deliciousness of Flesh (Del‐F)" and the buying decision were significant. In addition, the relationship between the saturation levels set by Adobe Photoshop and Chroma difference (ΔC*ab) indicated that the appropriate Chroma difference (ΔC*ab) should be in the range of 21 to 28 to achieve the highest satisfaction and a predicted probability of buying of more than 90%. [ABSTRACT FROM AUTHOR]

Presents a study that developed a photoreceptor charging method without corona discharge. Significance of photoreceptor charging in the electrophotographic printing process; Analysis of the effect of rubbing a photoreceptor with magnetic conductive particles; Results and implications.

Presents a study which examined hole transport properties of resistive hydrogenated amorphous silicon. Experiment; Results and discussion; Conclusion.

Describes a photoreceptor charging method by rubbing with magnetic conductive particles. Details on the charging mechanism of particle charging; Depth of the trapped charges; Description of the proposed electrophotographic printing technology.