• Title/Summary/Keyword: vAm

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Study of the Energy Level Alignment of Organic Materials' Planar Junction Prepared by Electrospray Vacuum Deposition

  • Kim, Ji-Hun;Hong, Jong-Am;Seo, Jae-Won;Gwon, Dae-Gyeon;Maeng, Min-Jae;Park, Yong-Seop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.235-235
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    • 2012
  • We investigated the energy levels of valence region at the planar junction of poly (3-hexylthiophene) (P3HT) and C61-butyric acid methylester (PCBM) using ultraviolet photoemission spectroscopy (UPS) with ultra high vacuum. These are the most widely used materials for bulk heterojunction (BHJ) organic solar cells due to their high efficiency. In order to make the planar junction, we carried out the electrospray vacuum deposition (EVD) of PCBM onto spin-coated P3HT in high vacuum conditions (${\sim}10^{-5}-10^{-6}$). The planar junction interface exhibited 0.71 eV for the offset between P3HT HOMO and PCBM LUMO, which is different from the gap (0.85 eV) of individual values and is closer to the open circuit voltage of solar cells fabricated with the same material combination.

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Wake-up Schematic Design For Ultra Low Power USN/WBAN Sensor Node System (저전력 USN/WBAN 센서노드 시스템용 Wake-up 회로 설계)

  • Hwang, Ji-Hun;Roh, Hyoung-Hwan;Kim, Hyeong-Seok;Park, Jun-Seok
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1568_1569
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    • 2009
  • RFID 수동 태그의 동작 원리를 이용하여 USN/WBAN 센서 노드 시스템에 적용 가능한 웨이크 업 회로를 설계하였다. 웨이크 업회로 구성은 크게 전압 체배기, 복조기, 상태기계로 구성되었다. 상태 기계에 동작 가능한 전압을 공급하기 위해 전압 체배기는 문턱 전압 제거 방식을 적용한 구조를 사용하였고, 복조기 회로로는 AM 복조기로 구조가 간단한 포락선 검파기 방식을 사용하였다. 전압 체배기에 높은 전압이 인가될 경우 회로가 파괴되는 것을 막기 위해 제한 회로를 구성하여 최대 전압을 2.1V로 제한하였다. 또한 복조기에서는 안정적인 데이터 복조를 위해 비교기의 기준전압을 입력신호의 평균값을 사용한 슈미트 트리거 비교기를 사용하여 안정적으로 데이터를 추출하였다. 삼성 0.18um CMOS 공정을 이용하여 설계하였고, 측정 결과 전압 체배기의 체배 전압은 2.07~1.76V까지 체배 되는 것을 확인하였고, 복조기의 데이터 복조 역시 약 4M의 거리까지 데이터를 복조함을 확인하였다.

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Electrical Conduction Mechanism of AIN Insulator thin Film Fabricated by Reactive Sputtering Method for the Application of MIS Device (반응성 스퍼터링으로 제조한 MIS 소자용 AIN 절연박막의 전기전도 메커니즘)

  • Park, Jung-Cheul;Kwon, Jung-Youl;Lee, Heon-Yong;Chu, Soon-Nam
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.4
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    • pp.751-755
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    • 2007
  • We have studied the variable conditions of reactive sputtering to prepare AM thin film. The leakage current showed below $10^{-9}A/cm^2$ at the deposition temperature of $250^{\circ}C\;and\;300^{\circ}C$ in the field of 0.1 MV/cm, and it was gradually increased and to be saturated in 0.2 MV/cm. The C-V characteristics of the above mentioned deposition temperature conditions showed a deep depletion phenomenon at inversion region. The C-V characteristics showed similarly under the DC power conditions of 100 and 150 W but were degraded at 200W. When the DC power was 100, 200, and 300 W the dielectric breakdown phenomenon was shown in 2.8, 3.2 and 5.2 MV/cm, respectively. It was found that AIN film was dominated by Poole-Frenkel conduction mechanism.

The Polarographic Wave of Co (III)-Triethanolamine Complex (코발트(III)-Triethanolamine 錯鹽의 폴라로그라프波에 對하여)

  • Hwang Am Kim
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.34-37
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    • 1963
  • Cobalt(Ⅲ) ion gives two step waves with $E_{1/2}$-0.1V(?)(vs.S.C.E.) and $E_{1/2}$-1.37V(vs. S.C.E.) from a base electrolyte consisting of 0.1 M TEA+sodium borate+0.0002% gelatin. The first wave results from the reduction Co(Ⅲ) to Co(Ⅱ). The second wave corresponding to the reduction Co(Ⅱ) to Co(0) and this wave is diffusion controlled. The diffusion current constant of the second wave is 2.7. Under these-conditions, diffusion current of the second wave is proportional to the concentration of Co (Ⅱ) in the range of $10^{-3}{\sim}10^{-4}$ M.

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The Effect of Noise on the Normal and Pathological Voice (소음환경이 정상 및 병적음성에 미치는 영향)

  • Hong, Ki-Hwan;Yang, Yoon-Soo;Kim, Hyun-Gi
    • Speech Sciences
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    • v.9 no.4
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    • pp.27-38
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    • 2002
  • The purpose of this article is to present the acoustic parameters (VOT, jitter, shimmer, vF0, vAm, NHR, SPI, VTI, DVB, DSH) for consonants (/pipi/, /$p^{h}ip^{h}i$/, /p'ip'i/) and sustained vowels (/a/, /e/, /i/) produced by normal subjects and dysphonia patients at two vocal effort(normal, high) by Lombard effect using 60dB white noise. Lombard effect indicates the vocal effort increase in noisy situation. At normal vocal effort, in general the acoustic parameter values of patients are greater than normal. And in noisy situation, significant decrease of acoustic values is seen in normal compared with in dysphonia patients. The clinical implication of this finding, the vocal quality in dysphonia is not compensated by vocal effort as well as normal subjects because of the inefficiency caused by abnormal vocal fold appearance and function. And with this result, we can counsel that the voice quality can not be improved as well as the patient expect.

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Atomic Resolution Imaging of Rotated Bilayer Graphene Sheets Using a Low kV Aberration-corrected Transmission Electron Microscope

  • Ryu, Gyeong Hee;Park, Hyo Ju;Kim, Na Yeon;Lee, Zonghoon
    • Applied Microscopy
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    • v.42 no.4
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    • pp.218-222
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    • 2012
  • Modern aberration-corrected transmission electron microscope (TEM) with appropriate electron beam energy is able to achieve atomic resolution imaging of single and bilayer graphene sheets. Especially, atomic configuration of bilayer graphene with a rotation angle can be identified from the direct imaging and phase reconstructed imaging since atomic resolution Moir$\acute{e}$ pattern can be obtained successfully at atomic scale using an aberration-corrected TEM. This study boosts a reliable stacking order analysis, which is required for synthesized or artificially prepared multilayer graphene, and lets graphene researchers utilize the information of atomic configuration of stacked graphene layers readily.

The Influence of Dry Etching Process by Charged Static Electricity on LCD Glass

  • Kim, Song-Kwan;Yun, Hae-Sang;Hong, Mun-Pyo;Park, Sun-Woo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.77-78
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    • 2000
  • We verified the charged static electricity on LCD glass influences upon the etching uniformity of dry etching process by plasma. In the TFT-LCD manufacturing process, we mainly paid attention to eliminate the static electricity for TFT reliability. The static electricity caused the serious ununiformity of etching surface profile and etching rate in the dry etch process. Through our experiment on the made static electricity from -200V to -1000V, it was confirmed that the static electricity on LCD glass caused the etching rate variation of $1.5%{\sim}15%$. We recommend the etching process equipment for LCD manufacturing have to establish the soft X-ray exposure module system for eliminating the static electricity inside the loading and unloading chamber.

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A Supplementary Study for Sasangin Identifing (사상인변증(四象人辨證)의 확충(擴充)을 위한 연구(硏究) -[동의수세보원사상초본권(東醫壽世保元四象草本卷) 병변편(病變篇) 제오통(第五統)] 을 중심으로-)

  • Lee, Eui-Ju
    • Journal of Sasang Constitutional Medicine
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    • v.14 no.3
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    • pp.17-32
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    • 2002
  • Objectives ; A Supplementary Study for Sasangin Identifing is based on Chapter Pathophysiology Part V of [Donggyi Soose Bowon Chobonguan]. And I try to explain that with Sasang Constitutional Theory. After all I want this study given the basis of 'The Guideline of Sasangin's Diagnosis & Treatment(GSDT)'. Methods ; First, I divid ${\ulcorner}$part V${\lrcorner}$ into 4 cartegories (Normal Condition, Abnormal Condition, good or bad Condition, Better or Worse Condition). And then each symtom is analyzed by Sasang Constitutional Medicine(SCM). Conclusions; I am sure that it gives the first step toward Indentifying Sasangin of [Donggyi Soose Bowon]. All of Sasangin Identifing Supplementary are analyzed by SCM. They are divided the identifing for Sasangin classification and Sasangin diagnosis of the disease. And this study will give the basis of ‘GSDT’.

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AC Plasma Power Supply with Variable Voltage and Variable Frequency (가변전압 가변주파수(VVVF) 교류 플라즈마 전원장치)

  • Shin Wan-Ho;Yun Kee-Pok;Jeoung Hwan-Myoung;Choi Jae-Ho
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.1205-1207
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    • 2004
  • AC plasma power supply is used to control a ozone generator and a air pollution gas. AC plasma power supply is composed of power semiconductor switch devices and control board adapted SHE(Selected Harmonic Elimination) PWM method. AC plasma power supply with sinusoidal VVVF(variable voltage and variable frequency) is realized. Its output voltage range is from 0 [V] to 20[kV] and output frequency range is from 8[kHz] to 20[kHz]. Using proposed system, AC high voltage and high frequency discharge is tested in the DBD(dieletric barrier discharge) reactor, and the space distribution of a its non-thermal plasma is observed. In spite of the increasement of voltage and frequency, the proposed system have a stable operation characteristics. It is verified by the experimental results.

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Electrical Properties of ITO/TiO$_2$/Se Solar Cell (ITO/TiO$_2$/Se 태양전지의 전기적특성에 관한 연구)

  • 문수경;박현빈;구할본;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.05a
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    • pp.114-116
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    • 1992
  • ITO/TiO$_2$/Se solar cell were fabricated by vacuum deposition method, the Se and TiO$_2$were deposited on the ITO/Glass. Prior to the electrical properties of film, the provide Te between the ITO and the Se film were deposited by substrate temperature 20[$^{\circ}C$] and evaporation time 15[min], next time TiO$_2$ were treated by rf-magnetron sputtering in substrate temperature 250[$^{\circ}C$]. Fabricated ITO/TiO$_2$/Se solar cell were as follows : Open Voltage V$\_$oc/=848[mV], Short Circuit Current I$\_$sc/=10.79[mA/$\textrm{cm}^2$]. Fill Factor FF=0.518, energy conversion efficiency η=4.74[%] under the illumination of AM 1.

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