• Journal of Electrical Engineering and Technology
• /
• v.1 no.2
• /
• pp.233-236
• /
• 2006

A 3-D numerical simulation of a buried-channel CCD (Charge Coupled Device) with a deep depletion has been performed to investigate its electrical and physical behaviors. Results are presented for a deep depletion CCD (EEV CCD12; JET-X CCD) fabricated on a high-resistivity $(1.5k\Omega-cm)\;65{\mu}m$ thick epi-layer, on a $550{\mu}m$ thick p+ substrate, which is optimized for X-ray detection. Accurate predictions of the Potential minimum and barrier height of a CCD Pixel as a function of mobile electrons are found to give good charge transfer. The depletion depth approximation as a function of gate and substrate bias voltage provided average errors of less than 6%, compared with the results estimated from X-ray detection efficiency measurements. The result obtained from the transient simulation of signal charge movement is also presented based on 3-Dimensional analysis.

• Proceedings of the KSME Conference
• /
• 2003.04a
• /
• pp.1684-1689
• /
• 2003

Dielectric Barrier Discharges (DBD) in oxygen and air are well established for the production of large quantities of ozone and are more recently being applied to a wider range of after treatment processes for HAPs(Hazardous Air Pollutants). The potential use as a charger for particle collection are not well known. In this work, we measured charge distribution of nanometer or submicron sized particles passing through the dielectric barrier discharge reactor. The bipolar charge characteristics of particles passing DBD reactor were investigated. Fluorometric method using uranine particles and a fluorometer was employed to examine the bipolar charging characteristics of the charged particles by DBD reactor. Finally, the charge distributions of particles were determined from the electrical mobility classification using DMA.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.186.1-186.1
• /
• 2014

Graphene, which is a 2-dimensional carbon material, has been attracting much interest due to its unique properties and potential applications. So far, many interesting experimental and theoretical works have been done concerning the electronic properties of graphene on various substrates. Especially, there are many experimental reports about doping in graphene which is caused by interaction between graphene and its supporting substrates. Here, we report the study of charge transfer between graphene and oxide substrates using density functional theory (DFT) calculations. In this study, we have investigated the charge transfer related with graphene considering various oxide substrates such as SiO2(0001) and MgO(111). Details in charge transfer between graphene and oxides are analyzed in terms of charge density difference, band structure and work function.

• 전기의세계
• /
• v.28 no.10
• /
• pp.48-54
• /
• 1979

The electrification phenomena of polymerized materials is governed by the competitive processes of the charge generation and the charge dissipation. In this paper, The charged particles were supplied on the naked upper surface of the polyethylene film from a point corona discharge with a screen electrode which controls the potential difference across the film. The charging current with the corona charging was found to be larger than that obtained with the electric charging on the MIM structure and the discharge current was found to flow in the same direction as that of the charging current. these results can suggest that the charge injection occurs from the interface between the polethylene surface and the accumulated charge layer, the injected charge are trapped and the space charge is established.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.1151-1153
• /
• 2004

In this paper, small-signal modeling and closed-loop performance of charge control employed to an asymmetrical half-bridge (ASHB) dc-to-dc converters are investigated. The charge control is selected as an alternative to the conventional voltage-mode control and peak current-mode (PCM) control, which have their respective limitations and problems when adapted to ASHB dc-to-dc converters. The current-loop dynamics of the charge control are presented in comparison with those of voltage-mode and PCM control. This paper demonstrates that the charge control offers better dynamic performance compared to voltage-mode control and superior noise characteristics compared to PCM control. The potential problem of charge control are also addressed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.35 no.5
• /
• pp.494-498
• /
• 2022

In this study, SiO₂ 20 phr, ATH 70 phr, and platinum flame retardant were mixed with raw silicone rubber and -10 kV was applied to measure electrostatic charge attenuation voltage, surface resistance, and volume resistance, and the following conclusions were obtained. When the platinum flame retardant was 0 phr, the humidity 74.6% and the temperature was 21.8℃, the potential was half-reduced to 0.63 kV, 0.57 kV, and 0.44 kV when the applied voltage was changed from -10 kV to -8 kV, and the time halved to 50% was increased to 2.40 seconds, 2.47 seconds, and 2.61 seconds. It was confirmed that as the platinum flame retardant increased from 0.1 to 0.3 phr, the potential half-reduced to 0.67 kV, 0.60 kV, and 0.595 kV decreased, and the charge potential attenuation time half-reduced to 50% decreased to 3.44 seconds, 1.78 seconds, and 1.60 seconds. It was confirmed that the surface resistance increased as the humidity decreased, and the volume resistance decreased as the platinum flame retardant increased.

• Fibers and Polymers
• /
• v.5 no.2
• /
• pp.151-155
• /
• 2004

Cold plasma of $O_2$ or Ar was irradiated on hydrophobic Kapton surface to attenuate or remove the electrostatic potential. A measurement on charge dissipation speed clarifies the obscure effect of plasma. These consequences reveal that $O_2$ plasma etching is more effective than Ar plasma. After 30 days, the dissipation speed of accumulated charge on initially etched sample has not changed under summer season.

• Journal of the Korean Wood Science and Technology
• /
• v.18 no.1
• /
• pp.24-30
• /
• 1990

This study was attempted to propose a method evaluating fixation of active ingredients in Copper-Chromium-Arsenic preservatives treatment. Fixated amount of active ingredients on wood was obtained by measuring the density of surface electric charge based on $\varsigma$ potential. Data accumulated from density of surface electric charge showed that the fixated amount of preservatives on wood increased linearly as concentration of treating solution increaced, which indicatied quantitative reactions in fixation of preservatives.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.115.1-115.1
• /
• 2014

Atom-thick 2-dimensional materials such as graphene, h-BN and MoS2 hold substantial potential for applications in future molecular-scale integrated electronics, transparent conducting membranes, nanocomposites, etc. From a fundamental point of view, 2-dim crystal-solid substrates can also serve as a unique system to study various physicochemical phenomena occurring at low dimensions or interfaces. In this talk, I will present our recent Raman spectroscopy studies on the surface science problems of graphene: interfacial charge transfer, molecular diffusion in confined space and structural deformation.

• Nuclear Engineering and Technology
• /
• v.29 no.6
• /
• pp.451-458
• /
• 1997

Signal shapes from a closed-ended coaxial HPGe detector are investigated by numerical methods. The detector used in this study has a volume of 72 ㎤ with relative efficiency of 15%. The electric field and potential distributions in the detector are determined by solving the Poisson equation at the depletion and operating bias. Hence the time dependent signal shapes induced on the electrode are obtained from the energy balance consideration and tv solving the equation of motion for the charge carriers. For various initial positions of a charge carrier pair, the collection times of induced charge vary in the range of 70 - 404 nsec.