• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.6 no.1
• /
• pp.24-28
• /
• 2005

A micromachined biochip with a three dimensional silicon chamber was developed for the construction of biosensors. Anisotropic etching was used fur the formation of the chamber on the p-type silicon wafer(100) and then was glued to the Pyrex glass bottom-substrate with pre-deposited platinum electrode. The electrochemical characterization of its Pt electrode and Ag/AgCl reference electrode was investigated.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.34 no.9
• /
• pp.341-348
• /
• 1985

This paper deals with a surface charge simulation method of calculating three-dimensional electric fields and capacitance. The principle is to divide the electrode surface into rectangular or triangular elements of which charge density is the linear function of the electrode coordinate and to formulate a linear equation for the coefficients of charge density function and to determine those coefficients by boundary conditions. It has been shown that the method can give satisfactory results for thin rectangular plates where the other methods is difficult to be applied.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2000.11a
• /
• pp.95-98
• /
• 2000

Film bulk acoustic resonator used in microwave region can be analyzed by one-dimension Mason's model and one-dimensional numerical method, but it had several constraints to analyze effects of area variation, electrode-area variation, electrode-shape variation and spurious characteristics. To overcome these constraints film bulk acoustic resonator must be analysed by three dimensional numerical method. So, in this paper three dimensional finite element method was used to analyze several moles of resonance and was compared with the one dimension Mason's model analysis and analytic solution.

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.285-286
• /
• 2007

Current distributions according to electrode patterns in vertical structured InGaN/GaN LED (light emitting diode) were investigated quantitatively by utilizing three dimensional electrical circuit modeling method. The uniformity of the injected current density in the active layer was compared among different electrode patterns. It was found that the current uniformity was greatly dependent on the electrode pattern in vertical InGaN/GaN LEDs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.36 no.2
• /
• pp.175-185
• /
• 2023

A hybrid supercapacitor is a promising energy storage device in view of its excellent capacitive performance. Commercial three-dimensional foam nickel (Ni) can be used as an ideal framework due to an interconnected network structure. However, its application as an electrode material for supercapacitors is limited due to its low specific capacity. Herein, we report a successful growth of MnO₂ on the surface of graphene by a one-step hydrothermal method; thus, forming a three-dimensional MnO₂-graphene-Ni hybrid foam. Our results show that the mixed structure of MnO₂ with nanoflowers and nanorods grown on the graphene/Ni foam as a hybrid electrode delivers the maximum specific capacitance of 193 F·g^-1 at a current density 0.1 A·g^-1. More importantly, the hybrid electrode retains 104% of its initial capacitance after 1,000 charge-discharge cycles at 1 A·g^-1; thus, showing the potential application as a stable supercapacitor electrode.

• Journal of Sensor Science and Technology
• /
• v.29 no.4
• /
• pp.232-236
• /
• 2020

Three-dimensional (3D) multilayered Pt electrodes were fabricated to develop a porous electrode using a pattern-transfer printing process. The Pt thin films were deposited using a transferred sputtering pattern having a 250 nm line width on the substrate, and the uniform line patterns were efficiently transferred using our proposed method. Temperature-programmed desorption (TPD) analyses were used to evaluate the porosity of the electrodes. It was possible to distinguish between two resolved maxima at 168 and 227 ℃, which could be described in terms of desorption reactions on the Pt (111) planes. The results of the TPD analysis of the 3D and multilayered Pt electrodes prepared through transfer printing were compared to those of an electrode fabricated through screen printing using a commercial Pt-carbon paste commonly used as porous electrodes. It was confirmed that the 3D multilayered electrodes exhibited a desorption concentration approximately 100 times higher than that of the Pt-carbon composite electrode, and the desorption concentration increased by approximately 0.02 mg/mol per layer. The 3D multilayered electrode effectively functions as a porous electrode and a catalyst.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.21 no.4
• /
• pp.368-375
• /
• 2008

In this paper, we calculated the pixel and all the inter-electrode capacitances in a unit pixel of three kinds of TFT-LCD modes in order to realize the full color image. And we analyzed the effect on applied voltage. We fixed size of sub-pixel and designed a unit pixel of three kinds of TFT-LCD modes. We calculated rigorously the pixel and all the inter-electrode capacitances by the three dimensional simulation. And we expanded one pixel into whole panel using H-SPICE. As a result, we calculated the RMS voltage and kickback voltage which most affect gray scale of the pixel and calculated the number of bit according to permissible range of minimum gray scale using V-T curve.

• KSBB Journal
• /
• v.4 no.2
• /
• pp.150-156
• /
• 1989

The chaacterisitics of a commercial membrance-coverd electrode in air-saturated saline solution were investigated in terms of a steadystate one-dimensional model. The electrode system miiersed in an aqueous medium consists of three layers: an external concentration boundary layer, a membrance, and an inner electrolyte layer. The membrance can be permeabld to the water and impermeable to the ionic species. In stationary midium, the water migrates from the external medium to the inner electrolyte layer until a thermodynamic equilibrium is reached. In a following midium, however, there is a reverse direction of water movement due to the hyrodynamic pressure differential until both thickness of the electrolyte layer and the membrance are equal.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.12
• /
• pp.3993-3997
• /
• 2012

Three-dimensional porous nickel foam was used as a current collector to prepare a Co-Ni oxide/Ni foam electrode for a supercapacitor. The synthesized Co-Ni oxide was proven to consist of mixed oxide phases of $Co_3O_4$ and NiO. The Co-Ni oxide/Ni foam electrode prepared was characterized by morphological observation, crystalline property analysis, cyclic voltammetry, and impedance spectroscopy. Cyclic voltammetry for the electrode showed high specific capacitances, such as 936 F $g^{-1}$ at 5 mV $s^{-1}$ and 566 F $g^{-1}$ at 200 mV $s^{-1}$, and a comparatively good cycle performance. These improved results were mainly due to the dimensional stability of the nickel foam and its high electrical contact between the electrode material and the current collector substrate.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.5 no.1
• /
• pp.30-37
• /
• 2005

We present an air bridge type electrode system with tunable electrode distance for detecting electroactive biomolecules. It is known that the narrower gap between electrode fingers, the higher sensitivity in IDA (interdigitated array) electrode. In previous researches on IDA electrode, narrower patterning required much precise and expensive equipment as the gap goes down to nanometer scale. In this paper, an improved method is suggested to replace nano gap pattering with downsizing electrode distance and showed that the patterning can be replaced by thickness control using metal deposition methods, such as electroplating or metal sputtering. The air bridge type electrode was completed by the following procedures: gold patterning for lower electrode, copper electroplating, gold deposition for upper electrode, photoresist patterning for gold film support, and copper etching for space formation. The thickness of copper electroplating is the distance between upper and lower electrodes. Because the growth rate of electroplating is $0.5{\mu}m\;min^{-1}$, the distance is tunable up to hundreds of nanometers. Completed electrodes on the same wafer had $5{\mu}m$ electrode distance. The gaps between fingers are 10, 20, 30, and $40{\mu}m$ and the widths of fingers are 10, 20, 30, 40, and $50{\mu}m$. The air bridge type electrode system showed better sensitivity than planar electrode.