• 제목/요약/키워드: Hole density

검색결과 442건 처리시간 0.035초

Interfacially Controlled Hybrid Thin-film Solar Cells Using a Solution-processed Fullerene Derivative

  • 남상길;송명관;김동호;김창수
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.190.2-190.2
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    • 2014
  • We report the origin of the improvement of the power conversion efficiency (PCE) of hybrid thin-film solar cells when a soluble C60 derivative, [6,6]-phenyl-$C_{61}$-butyric acid methyl ester (PCBM), is introduced as a hole-blocking layer. The PCBM layer could establish better interfacial contact by decreasing the reverse ark-saturation current density, resulting in a decrease in the probability of carrier recombination. The power conversion efficiency of this optimized device reached a maximum value of 8.34% and is the highest yet reported for hybrid thin-film solar cells.

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직접 디젤 연료분사계의 분사 특성과 기관 성능 개선에 관한 연구 (Injection Feature and Engine Performance Improvement of the Direct Diesel Fuel Injection System)

  • 윤천한;김경훈
    • 한국분무공학회지
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    • 제7권1호
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    • pp.1-6
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    • 2002
  • This study has focused on using fuel injections as variables for measuring performance and reducing exhaust gas in turbo-charger diesel engine. In experiments, we changed nozzle hole diameter, diameter of an injection pipe, and injection timing as variable. The results show that torque. fuel consumption and smoke are reduced as nozzle hole diameter decreases, while NOx increases. When the diameter of injector is reduced, torque, fuel consumption and smoke are deteriorated, but NOx is decreased. In addition, when the time for injection is advanced. torque, fuel consumption and smoke are improved, but the density of NOx is increased.

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The effects of As addition on the transport property of a-Se:As films using the moving photo-carrier grating technique

  • Park, Chang-Hee;Lee, Kwang-Sei;Kim, Jeong-Bae;Kim, Jae-Hyung
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.252-253
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    • 2005
  • The effects of As addition in amorphous selenium (a-Se) films on the carrier mobilities and the recombination lifetime have been studied using the moving photo-carrier grating (MPG) measurements. The electron and hole mobility, and recombination lifetime of a-Se films with arsenic (As) additions up to 1% have been obtained. We have found an increase in hole drift mobility and recombination lifetime, especially when 0.3% As is added into a-Se film, whereas electron mobility decreases with As addition due to the defect density from shallow traps.

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Sensitivity Analysis of Plasma Charge-up Monitoring Sensor

  • Lee Sung Joon;Soh Dea-Wha;Hong Sang Jeen
    • Journal of information and communication convergence engineering
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    • 제3권4호
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    • pp.187-190
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    • 2005
  • High aspect ratio via-hole etching process has emerged as one of the most crucial means to increase component density for ULSI devices. Because of charge accumulation in via-hole, this sophisticated and important process still hold several problems, such as etching stop and loading effects during fabrication of integrated circuits. Indeed, the concern actually depends on accumulated charge. For monitoring accumulated charge during plasma etching process, charge-up monitoring sensor was fabricated and tested under some plasma conditions. This paper presents a neural network-based technique for analyzing and modeling several electrical performance of plasma charge-up monitoring sensor.

전파 Jet 3C449의 동역학적 모형

  • 정홍대;윤홍식;최승언
    • 천문학논총
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    • 제4권1호
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    • pp.1-15
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    • 1989
  • A jet plasmoid model for 3C.449 has been constructed by introducing a plasma.ejecting black hole orbiting around the center of its parent cD galaxy. We examined the characteristics of the jet trajectory by varying the values of (1) orbiting radius and velocity of the black hole, (2) plasma ejection velocity, (3) size, mass and space velocity of the parent galaxy, (4) size of the galactic core and (5) the density of the intergalactic medium. In our model calculation the effect of the gravity by the parent galaxy and the ram pressure by the intergalactic medium have been taken in account. It is found that our dynamical model accounts reasonably well for the observed structure of 3C449. Our proposed model suggests that the buoyancy force near the galactic center plays an important role in the formation of the curved structure of the radio jet.

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Sensitivity Analysis of Plasma Charge-up Monitoring Sensor Using Neural Networks

  • Lee, Sung-Joon;Kim, Sun-Phil;Soh, Dae-Wha;Hong, Sang-Jeen
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 추계종합학술대회
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    • pp.303-306
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    • 2005
  • High aspect ration via-hole etching process has emerged as one of the most crucial means to increase component density for ULSI devices. Because of charge accumulation in via hole, this sophisticated and important process still hold several problems, such as etching stop, loading effects during fabrication of integrated circuits. Indeed, the concern actually depends on accumulated charge. For monitoring accumulated charge during plasma etching process, charge-up monitoring sensor was fabricated and tested under some plasma conditions. This paper presents a neural network-based technique for analyzing and modeling several electrical performance of plasma charge-up monitoring sensor.

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전하 트랩 및 주입 문제를 해결하기 위한 비정질 셀레늄 필름의 계면 특성 (Interfacial Properties of a-Se Thick Films to Solve Charge Trap and Injection Problems)

  • 조진욱;최장용;박창희;김재형;이형원;남상희;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.497-500
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    • 2001
  • Due to their better photosensitivity in X-ray, the amorphous selenium based photoreceptor is widely used on the X-ray conversion materials. It was possible to control the charge carrier transport of amorphous selenium by suitably alloying a-Se with other elements(e,g. As, Cl). The charge transport properties of amorphous Selenium is decided on hole which is induced from metal to selenium in metal-selenium junction and which is transferred in a-Se bulk. This phenomenon is resulted of changing electric field owing to increasing of space charge by deep trap of a-Se bulk. In this paper, We dopped the chlorine to compensate deep hole trap and deposited blocking layer using dielectric material to prevent from increasing space charge for injection charge between metal electrode and a-Se layer. We compared space charge and the decreasing of trap density through measuring dark and photo current.

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전력케이블용 가교폴리에틸렌의 공간전하 극성측정기술에 관한 연구 (A Study on the Space Charge Polarity Measurement Teasurement Technology of Cross-Linked Polyethylene for Power Cable)

  • 국상훈;서장수;김병인;박중순
    • 한국조명전기설비학회지:조명전기설비
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    • 제6권6호
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    • pp.23-31
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    • 1992
  • Charged particle in the polymers is supposed to affect the electrical conduction and to lead them th dielectrical breakdown finally. So we measured the space charge distribution made by application of high electric field and evaluated the polarity of the charged particle affected on electrical conduction and space charge formed in the insulating materials by using temperature gradient thermally stimulated current measurement method(TG-TSC measurement). As a result, in the cross-linked polyethylene, A-peak was caused from dipole polarization, C-peak was caused from ionic space charge polarization and D-peak was injected trap hole. Also we found it crossible the evaluated the polarity of injected trap carrier and electron(or hole) of carrier trap in the cross-lined polyethylene. We found that ${\gamma}$-ray irradiated low density polyethylene had a relation to the electronic trap and we also could get the value of electric field distribution in the samples of which evaluation was available.

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NiO/AZO anode를 적용한 OLED의 정공주입 향상에 관한 연구 (A study on the enhancement of hole injection in OLED using NiO/AZO Anode)

  • 진은미;송민종;김진사;박춘배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.444-445
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    • 2007
  • Aluminum-doped zinc oxide (AZO) films are attractive materials as transparent conductive electrode because they are inexpensive, nontoxic and abundant element compared with indium tin oxide (ITO). AZO films have been deposited on glass (coming 1737) substrates by RF magnetron sputtering system. An ultrathin layer of nickel oxide (NiO) was deposited on the AZO anode to enhance the hole injections in organic light-emitting diodes (OLED). The current density-voltage and luminescence-voltage properties of devices were studied and compared with ITO device.

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다층구조 Organo-lanthanide OLED의 전기적 특성 (Electrical Properties of Multi-layer Organo-lanthanide OLEDs)

  • 하미영;김소연;문대규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 학술대회 및 기술세미나 논문집 디스플레이 광소자
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    • pp.83-84
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    • 2006
  • ITO/4, 4', 4"-tris (N -3 - methylphenyl - N - phenyl - amino) - triphenylamine, [m-MTDATA] / Terbium Iris - (1 - phenyl - 3 - methyl - 4 - (tertiarybutyryl) - pyrazol - 5 - one) triphenylphosphine oxide [$(tb-PMP)_3Tb-(Ph_3PO)$] / Mg:Ag devices were made to investigate its electrical and light emission properties. The thickness of m-MTOATA layer was varied from 0 to 80 nm. There was a threshold thickness for the sufficient hole injection. The insertion of 20 nm thick m-MTDATA layer between ITO and Tb-complex resulted in the right shift of current-voltage curve because of the insufficient hole injection. The low operating voltage can be obtained above the 40 nm of m-MTDATA layer. The insertion of m-MTDATA induced the increase of the background in the electroluminescence spectrum which was dependent on the current density of the devices.

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