• 한국광과학회:학술대회논문집
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• 한국광과학회 1997년도 학술대회지
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• pp.16-16
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• 1997

• 한국진공학회지
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• 제9권2호
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• pp.122-129
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• 2000

Mo이 코팅된 유리기판 상에 전기영동법으로 도포된 유리화 비정형 탄소분말의 전계방출 특성을 조사하였다. 탄소의 $sp^2$결합만으로 이루어진 유리화 비정형 탄소는 전계방출을 얻기 위한 초기화 공정 없이도 규칙적인 전계방출 거동을 보이고 있었다. 전자의 방출이 시작되는 임계전장의 크기는 3에서 4 MV/m 구간의 값을 가지고 있었으며, Fowler-Nordheim plot로부터 평가된 effective work function은 약 0.06 eV였다. 전류전압거동의 반복측정에 의해 관찰된 바와 같이 전계방출의 안정성 면에서 유리화 비정형 탄소는 Si tip보다 우수하였으며, 도포된 전체면적에서 전면발광의 가능성을 확인할 수 있었다. 이러한 결과는 탄소계 물질에서 관찰되는 전계방출이 탄소의 $sp^3$결합과 밀접하게 관련되어 있지 않으며, 전자가음극물질의 표면으로 이동하는데 필요한 전기전도성, 혹은 기판과 음극물질 계면에서의 전자이동 등이 전계방출의 거동을 결정하는 중요한 요인임을 보여주고 있다.

• 반도체디스플레이기술학회지
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• 제8권4호
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• pp.43-48
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• 2009

The aim of this paper is to describe the development of the electron-beam optic analysis algorithm for simulating the e-beam behavior concerned with electrostatic lenses and their focal properties in the micro-column of the multi-beam lithography system. The electrostatic lens consists of an array of electrodes held at different potentials. The electrostatic lens, the so-called einzel lens, which is composed of three electrodes, is used to focus the electron beam by adjusting the voltages of the electrodes. The optics of an electron beam penetrating a region of an electric field is similar to the situation in light optics. The electron is accelerated or decelerated, and the trajectory depends on the angle of incidence with respect to the equi-potential surfaces of the field. The performance parameters, such as the working distances and the beam diameters are obtained by the computational simulations as a function of the focusing voltages of the einzel lens electrodes. Based on the developed simulation algorithm, the high performance of the micro-column can be achieved through optimized control of the einzel lens.

• 한국공작기계학회논문집
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• 제17권4호
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• pp.15-21
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• 2008

Secondary electron detectors used in scanning electron microscope accept secondary electrons emitted from the specimen and convert them to an electrical signal that, after amplification, is used to modulate the gray-level intensities on a cathode ray tube, producing an image of the specimen. In order to acquire images with good qualities, as many secondary electrons as possible should be reached to the detector. To realize this it is very important to select an appropriate mounting position and angle of the detector inside the chamber of scanning electron microscope. In this paper, a number of numerical simulations are performed to explore the relationships between detection rates of secondary electrons and the values of some parameters, such as distances between the detector and sample, relative mounting positions of scintillator positioned inside the detector with respect to detector cover, two types of mounting angles of the detector. The relationships between detection rates and applied voltages to corona ring and faraday cage, and energies of secondary electrons are investigated as well.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1949-1954
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• 2012

We have developed a novel and eco-friendly synthetic route for the preparation of a two-dimensional layered zinc hydroxide with intercalated nitrate anions. The layered zinc hydroxide nitrate, called 'zinc basic salt', was, in general, successfully synthesized, using an electron beam irradiation technique. The 2-propanol solutions containing hydrated zinc nitrate were directly irradiated with an electron-beam at room temperature, under atmospheric conditions, without stabilizers or base molecules. Under electron beam irradiation, the reactive OH radicals were generated by radiolysis of water molecules in precursor metal salts. After further radiolytic processes, the hydroxyl anions might be formed by the reaction of solvated electrons and the OH radical. Finally, the $Zn_5(OH)_8(NO_3)_2{\cdot}2H_2O$ was precipitated by the reaction of zinc cation and hydroxyl anions. Structure and morphology of obtained compounds were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and high resolution transmission electron microscopy (HR-TEM). The chemical components of the products were determined by Fourier transform infrared spectroscopy (FT-IR) and elemental analysis (EA). The thermal behavior of products was studied by thermogravimetric (TG) and differential thermal analysis (DTA).

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.19.1-19.1
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• 2011

We report on the metal-insulator transition that occurs as a function of film thickness in ultrathin $La_{0.75}Sr_{0.25}VO_3$ films. The metal-insulator transition displays a critical thickness of 5 unit cell. Above the critical thickness, metallic films exhibit a temperature driven metal-insulator transition with weak localization behavior. With decreasing film thickness, oxygen octahedron rotation in the films increases, causing enhanced electron-electron correlation. The electron-electron correlations in ultrathin films induce the transition from metal to insulator in addition to Anderson localization.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권3호
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• pp.157-161
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• 2004

We present a simple analytical expression of plasma density by making use of the electron density equation to study the dynamic behavior of the corona discharge plasma. It assumes that a specified voltage profile is fed through the inner conductor of the reactor chamber consisting of two coaxial conducting cylinders. The analytical description is based on the electron continuity equation with ionization and attachment by electrons. It is found that the electron density profile calculated between two coaxial cylindrical electrodes depends very sensitively on the Profile of applied voltage. The analytical expression of plasma density and its generation will provide important scaling laws in the corona discharge plasma.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.921-924
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• 2006

In an attempt to enhance secondary electron emission characteristics of PDP, $12CaO{\cdot}7Al_2O_3$ electride was used as electron emission layer of PDP discharge cells. The compound was synthesized by Ca-treatment and its electron emission behavior during the glow discharge was measured. The results indicated that the spayed electride reduces the discharge voltage by ${\sim}20$ volts and decrease the discharge delay by more than 70%.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.505-506
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• 2006

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.3-6
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• 2002

Electron transfer is the major natural process governing the behavior of contaminants in soils and groundwaters. Biological degradation of contaminants, i.e., microbial transformation of hazardous compounds, is a well known irreversible electron transfer process. Although it is not well defined as a separate process, abiotic electron-transfer is also an important process for mobilizing/demobilizing inorganic contaminants in soils and groundwaters. Therefore, numerous remedial technologies have been developed on the basis of electron transfer concept. Among them,