광자에너지에 의한 TiN-Oxide 박막의 유전율 특성

정천옥,김병인,김창석 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

VLSI require thinner dielectric film and also larger capacitance. Most of such VLS I have MOS structures. For the research on this requirement, MOS capacitors were fabricated on the silicon wafer in four different thickness groups by RF sputtering method and investigated on their electrical and optical characteristics by photon energy variation. SiO film is used as the insulating layer and TIN film is chosen as the barrier against the diffusion of Al which is the terminal connected by ohmic contact because TIN has the advantageous properties such as good thermal stability and very low diffusion rate in spite of it's relatively low specific resistance.

Fabrication TiN/BaTiO₃ Thin Film by RF Sputtering and Characteristics of Photon Energy

Kim, Chang-Suk,Chung, Chun-Ock,Kim, Byung-In 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

This study evaporates the thickness of BaTiO₃differently by RF sputtering on Si wafer with N-Type 100 direction of substrate and manufactures BaTiO₃/TiN structure evaporating TiN for diffusion barrier on it. ε1 has larger value initially as the thickness is thicker, but it is decreased as the photon energy is increased and in ε2 value, as the thickness is thicker, TIN with middle dielectric layer has large value and thin film which TIN is not evaporated is decreased. In permittivity of thin film which evaporates TIN film on the upper part of BaTiO₃thin film according to the increase of photon energy, ε1 of real number has large value and ε2 of imaginary number has small value as the thickness is thinner. Therefore, when TIN thin film is evaporated on BaTiO₃, it obtains better photon energy property than the case that Tin is not evaporated and it is expected that good reproduction is resulted in applying to optical element.

ZnO/TiO₂ 박막 제작과 유전율 특성

김창석,최창주,이우선,오무송,김태성,김병인 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

In this study, ZnO is evaporated to be coated on n-type Si wafer substrate. Refractive coefficient of thin film that is evaporating TiO₂onto ZnO increases linearly as thickness is getting thinner to have high value and high angle and it satisfies theoretical equation I(x)=Io exp (-αx) theory that represents the strength of photon energy advancing through ZnO thin film. And dielectric constant of TiO₂thin film evaporated onto ZnO is high and ε₂ is smaller than ε₁. The specimen TiO₂thin film evaporated onto ZnO has much higher dielectric constant when photon energy is increased.

기체 주입 Ladle내에서 유동특성에 관한 연구

오율권,서동표 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.1

In the air-water model, the characteristics of flow parameters were experimentally investigated. When gas was injected into the liquid bath, several flow patterns were observed bubble-liquid plumb, the spout flow that occurred at the free surface, liquid circulation flow by bubble's behavior, etc. In the pure liquid region, the large and small several vortices were formed and irregularly circulated. These irregular repetition and circulation play a important role of mixing in the bath. The vortices were developed in the upper and the side wall regions and the movement of flow in the low region was very small. It is known as "dead zone". The bubble rise velocity in the bottom region was relatively lower than in the upper region because the energy generated by bubbles' behavior in the near nozzle region was almost converted into kinetic energy. But bubble rise velocity increases with the increasing the axial distance since kinetic energy of bubbles is added to buoyancy force.

SrTiO₃ 박막 제작과 Photon Energy 특성

정수복,정천옥,김병인 조선대학교 에너지.자원신기술연구소 1997 에너지·자원신기술연구소 논문지 Vol.19 No.2

SrTiO₃with nonpolarity among ferroelectrics by RF sputtering as dielectric layer. produces thin film of Si/SrTiO₃and Si/Ti/SrTiO₃of MOS structure using Ti as buffer layer. measures and examines the electrical features with optical photon energy ferroelectrics oscillation occurs by the interaction within a crystal by light temperature and the absorption of thin film with Ti as buffer layer is increased. It is found that the peak of dielectric constant value of Ti/SrTiO₃thin film has low values and is appeared late and as dipole which is found in dielectric is shown, the experiment satisfies the theory. In the nature of dielectric constant by photon energy, imaginary value is higher and current variation slope of thin film of thick SrTiO₃has lower values in reverse bias.

Hot Wall Epitaxy(HWE)에 의한 CdGa₂Se₄/GaAs epilayer 성장과 광전기적 특성

백승남,홍광준 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.1

The stochiometric mix of evaporating materials for the CdGa₂Se₄single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, CdGa₂Se₄mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were 630℃ and 420℃, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of CdGa₂Se₄single crystal thin films measured from Hall effect by van der Pauw method are 8.27×10^(17) ㎤, 345 ㎠/V ·s at 293 K, respectively. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the CuInSe₂ single crystal thin film. We have found that the values of spin orbit splitting △So and the crystal field splitting △Cr were 106.5 meV and 418.9 meV at 10 K, respectively. From the photoluminescence measurement on CdGa₂Se₄single crystal thin film, we observed free excition (Ex) existing only high quality crystal and neutral bound exicition (D^(0) ,X) having very stron peak intensity. Then, the full-width-at-half-maximum(FWHM) and binding energy of neutral donor bound excition were 8 meV and 13.7 meV, respectivity. By Haynes rule, an activation energy of impurity was 137 meV.

센서구동 방식에 의한 태양추적 시스템

박정국,최연옥,조금배,최창주 조선대학교 에너지.자원신기술연구소 2004 에너지·자원신기술연구소 논문지 Vol.26 No.2

Nowaday, almost of practical energy comes from the fossil fuel, such as coal, oil and gas. But those methode causes the environmental pollution. Photovoltaic systems are considered as a alternative energy source to overcome the shortage of electricity in the future. Photovoltaic system is easier to operate and maintain than the other power generating system since it generally contains no moving parts, operate silently and require very little maintenance. In this paper, it is proposed 150[W] solar tracking system, the system designed as the normal line of the solar cell always runs parallel the ray of the sun. This design can minimize the cosign loss of the system.

ZnGa₂O₄및 ZnGa₂O₄: Er^(3+) 형광체의 광학적 특성 연구

최성휴,서남희,김요완 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

ZnGa₂O₄ 및 ZnGa₂O₄:Er^(3+) 형광체의 결정구조와 광학적 특성을 측정하였다. 이 형광체는 공간군이 Fd3m에 속한 Cubic구조로 결정화 되었으며, 순수한 결정의 격자상수는 ZnGa₂O₄ 경우 a=8.3348Å이었고, 불순물 erbium 첨가한 결정의 격자상수는 a=8.3354Å이다. 기초흡수단 영역에서 측정한 ZnGa₂O₄의 직접전이 에너지 간격은 297K에서 3.057eV으로 주어졌고, erbium 불순물 첨가하였을 때 광학적 에너지 간격은 3.037eV이었다. 300K에서의 600~800nm영역에서 측정된 ZnGa₂O₄:Er^(3+) 형광체의 PL spectra는 660~712nm 영역에서 erbium 이온에 기인한 5개의 예리한 피크가 관찰되었다. Undoped ZnGa₂O₄phosphors crystallized in the cubic (space group Fd3m) with lattice constant a =8.3348Å. The lattice constant of ZnGa₂O₄:Er^(3+) was given as a=8.3354Å. The optical absorption measured near the fundamental band edge showed that the optical energy band structure of these compounds had a direct and indirect band gap, the direct energy gaps are found to be 3.057eV for ZnGa₂O₄, and 3.037eV for ZnGa₂O₄:Er^(3+) at 297K. The photoluminescence spectra of ZnGa₂O₄:Er^(3+) measured in the wavelength ranges of 600-800nm at 300K are observed in the regions 660~712nm and five sharp emission peak due to Er^(3+)ion.

DEREGULATION OF THE U.S. ELECTRIC UTILITY INDUSTRY

Youn, Luis T.,Kim, Chang suk,Chen, Jen-shiun 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

In 1978, the U.S. Congress passed the public Utility Regulatory Policies Act (PURPA) that would end the monopoly of electric generation by the electric utilities. It allowed competition in the electric generation market by introducing the non-utility independent power producers (or qualifying facilities). In 1992, the National Energy policy Act addresed all major elements of mational energy supply and use. It marked the end of a highly regulated and structured period for electric utilites by changing federal policies governing the generation and sale of electric power in the wholesale marketplace. since then despite doubts about whether the electric utility industry should be deregulated or not, the deregulation process has accelerated and is moving fast toward wholesale and retail competitions. This paper gives an overview of the deregulation process of eletric utilty ondustry in the U.S and discusses problems amd questions associated with it.

자기진단형 위상제어에 의한 단상유도전동기의 특성 및 모니터링 시스템에 관한 연구

조금배,박수강,백형래,임양수,이성길 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.2

The three-phase induction motor is rugged, reliable, long-lived, self-starting, smooth-running. But it is relatively inexpensive and three-phase power in not available everywhere, so if possible we need single-phase motor with the same characteristics. In fact, single-phase induction motors have excellent characteristics and outnumber the three-phase variety. Most of the small electric motors used in home, farm, or office are single-phase induction motors of one type or another. This electric motors application field need most energy saving type drive according to enlargement of electronic goods and to tend high class. The paper is proposed a various phase control methods for energy saving of single- phase induction motor. The controllers that are embodied by each method can use by various usage according to each performance and it is considered that application may help in the electrical energy saving because is possible to other electrical appliances.