• 제목/요약/키워드: Device degradation

검색결과 476건 처리시간 0.031초

다층막 구조를 이용한 유기 EL소자의 제작과 특성에 관한 연구 (Preparation and Characteristics of Organic Electroluminescence Devices Using Multilayer structure with Carrier Transport Materials)

  • 이상윤;김태완;최종선;김영관;김정수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.249-252
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    • 1997
  • Electroluminescence(EL) devices based on organic thin layers have attracted lot of interests because of their possible application as large-area display-emitting display. One of the problems of such devices is lifetime of the cell, where the degradation of the cell is partially due to the crystalliyzation of organic layers. In large part, this problem can be solved by using a multilayer device structure prepared by vapor deposition technique. In this study, blue light-emitting multilayer organic electroluminescence devices were fabricated vsing Poly (9-vinylcarbaEole) (PVK) and 2- (4-tert-butylphenyl)-5-(4$^{#}$-bis-phenyl) 1,3,4-oxadiazole (PBO) as hole trasport and electron transport material, respectively, where trim(8-hyd roxyquinolinate) aluminum (Al $q_3$) was used as a luminescenct material. A cell structure of glass sub- strate/indume-tin-oxide(ITO)/PCK/Al $q_3$/PBD/Mg:In was employed. Blue emission peak at 510nm was observed with this cell structure.e.

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Drain-current Modeling of Sub-70-nm PMOSFETs Dependent on Hot-carrier Stress Bias Conditions

  • Lim, In Eui;Jhon, Heesauk;Yoon, Gyuhan;Choi, Woo Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권1호
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    • pp.94-100
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    • 2017
  • Stress drain bias dependent current model is proposed for sub-70-nm p-channel metal-oxide semiconductor field-effect transistors (pMOSFETs) under drain-avalanche-hot-carrier (DAHC-) mechanism. The proposed model describes the both on-current and off-current degradation by using two device parameters: channel length variation (${\Delta}L_{ch}$) and threshold voltage shift (${\Delta}V_{th}$). Also, it is a simple and effective model of predicting reliable circuit operation and standby power consumption.

Influence of Substrate Thermal Conductivity on OLED Lifetime

  • Chung, Seung-Jun;Lee, Jae-Hyun;Jeong, Jae-Wook;Kim, Jang-Joo;Hong, Yong-Taek
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1026-1029
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    • 2008
  • Temperature increase during OLED operation can significantly degrade the device lifetime. By using top-emission OLEDs fabricated on glass and silicon substrates that have different thermal conductivities, we found that efficient heat dissipation and corresponding lifetime improvement can be obtained by making a direct contact between the OLED anode and the high thermally-conductive silicon substrate. We describe substrate-dependent OLED heat dissipation behavior and OLED lifetime improvement by using infrared camera images and constant current stress test methods.

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Nonvolatile Semiconductor Memories Using BT-Based Ferroelectric Films

  • Yang, Bee-Lyong;Hong, Suk-Kyoung
    • 한국세라믹학회지
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    • 제41권4호
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    • pp.273-276
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    • 2004
  • Report ferroelectric memories based on 0.35$\mu\textrm{m}$ CMOS technology ensuring ten-year retention and imprint at 175$^{\circ}C$. This excellent reliability resulted from newly developed BT-based ferroelectric films with superior reliability performance at high temperatures, and also resulted from robust integration schemes free from ferroelectric degradation due to process impurities such as moisture and hydrogen. The superior reliabilities at high temperature of ferroelectric memories using BT-based films are due to the random orientation by special bake treatments.

Uniformity Optimization of TFTs Fabricated on 2-shot SLS-Processed Si Films

  • Turk, Brandon A.;Wilt, P.C. Van Der;Crowder, M.A.;Voutsas, A.T.;Limanov, A.B.;Chung, U.J.;Im, James S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1750-1755
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    • 2006
  • Nonoptimal placement of short-channel-length TFTs in large-grained polycrystalline Si films with a periodic microstructure, as for instance obtained via 2-shot SLS, can potentially lead to degradation in the overall uniformity of the resultant devices. In this paper, we explain and demonstrate that by simply introducing a well-defined misorientation between the devices and the periodic microstructure, it is possible to significantly reduce (and potentially entirely eliminate) the device nonuniformity problem that can arise from such a cause.

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PMD-1 층의 물질변화에 따른 소자의 전기적 특성 (Electrical Characteristics of Devices with Material Variations of PMD-1 Layers)

  • 서용진;김상용;유석빈;김태형;김창일;장의구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 D
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    • pp.1327-1329
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    • 1998
  • It is very important to select superior inter-layer PMD(Pre Metal Dielectric) materials which can act as penetration barrier to various impurities created by CMP processes. In this paper, hot carrier degradation and device characteristics were studied with material variation of PMD-1 layers, which were split by LP-TEOS, SR-Oxide, PE-Oxynitride, PE-Nitride, PE-TEOS films. It was observed that the oxynitride and nitride using plasma was greatly decreased in hot carrier effect in comparison with silicon oxide. Consequently, silicon oxide turned out to be a better PMD-1 material than PE-oxynitride and PE-nitride. Also, LP-TEOS film was the best PMD-1 material Among the silicon oxides.

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중합제 첨가에 의한 항력 감소 효과에 관한 실험적 연구 (Experimental Investigation of Drag Reduction by Polymer Additives)

  • 성형진;위장우;권순홍;전호환
    • 한국해양공학회지
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    • 제16권4호
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    • pp.1-6
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    • 2002
  • Experimental investigation of drag reduction by adding a polymer additive(polyacrylamid, N-401P) into water is carried out in a Circular Water Channel. The effect of viscosity, surface roughness and degradation as a function of running time is also measured with varying the concentration of polymer additives(20ppm,100ppm) and Reynolds numbers. Near and far wakes past a circular cylinder are observed by LDV. Drag forces are measured with a strain-gaged device. The experimental results show that around 5%-30% of drag reduction with the polymer solution are observed. The larger effects of drag reduction can be found at low range of Reynolds number, more roughened surface cylinder. The effect of polymer solution for near wakes is larger than for far wakes.

Position Control of Linear Actuator with Uncertain Time Delay in VDN

  • Kim, Jonghwi;Kiwon Song;Park, Gi-Sang;Park, Gi-Heung
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.118.2-118
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    • 2002
  • Uncertain time delay happens when the process reads the sensor data and sends the control input to the plant located at a remote site in distributed control system. As in the case of data network using TCP/IP, VDN that integrates both device network and data network has uncertain tim e delay. Uncertain time delay can cause degradation in stability of distributed control system based on VDN. This paper investigates the transmission characteristic of VDN and suggests a control scheme based on the Smith's predictor to minimize the effect of uncertain time delay. The validity of the proposed control scheme is demonstrated with tracking position control of experiments.

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고밀도 칩 신뢰성 개선을 위한 buffered deposition 소자구조에 관한 연구 (A Study on Buffered Deposition Device Structure to Improvement for High Density Chip Realiability)

  • 김환석;이천희
    • 한국시뮬레이션학회논문지
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    • 제17권2호
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    • pp.13-19
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    • 2008
  • 본 연구에서는 드레인 부근의 채널 영역에서 접합 전계를 줄이는 Buffered deposition 구조의 소자를 제안하였다. Buffered deposition 구조의 소자 제작은 첫 번째 게이트를 식각한 후에 NM1(N-type Minor1) 이온주입을 하고 다시 HLD막과 질화막을 덮어 식각하여 제작하였다. 이러한 Buffered deposition 구조는 전계를 줄이기 위한 버퍼층으로 되어 있으며 Buffered deposition 소자의 여러 가지 구조의 Hot carrier 수명을 비교하였으며 열화 특성도 분석하여 10년간의 Hot carrier 수명을 만족함을 증명하였다.

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성능이 서서히 저하되는 시스템의 신뢰도 척도 (Performance-Based Reliability Measures for Gracely Degrading Systems: the Concept)

  • Kim, Yon-Soo;Park, Sang-Min
    • 산업경영시스템학회지
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    • 제17권32호
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    • pp.227-232
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    • 1994
  • In the performance domain, physical performance is a measure that represents some degree of system, subsystem, component or device success in a continuous sense, as opposed to a classical binomial sense (success or failure). If applicable sensing and monitoring means exist, physical performance can be observed over time, along with explanatory variables or covariables. Performance-based reliability represents the probability that performance will remain satisfactory over a finite period of time or usage cycles in the future when a performance critical limit (which represents an appropriate definition of failure in terms of performance) is set at a fixed level, based on application requirements. In the case of inadequate knowledge of the failure mechanics, this physical based empirical modeling concept along with performance degradation knowledge can serve as an important analysis tool in reliability work in product and process improvement.

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