• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 하계종합학술대회 논문집(2)
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• pp.327-330
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• 2004

It is shown that the hot carrier degradation due to enhanced hot holes trapping dominates PMOSFETs lifetime both in thin and thick devices. Moreover, it is found that in 0.13 ${\mu}m$ CMOSFET the PMOS lifetime under CHC (Channel Hot Carrier) stress is lower than the NMOSFET lifetime under DAHC (Drain Avalanche Hot Carrier) stress. Therefore. the interface trap generation due to enhanced hot hole injection will become a dominant degradation factor. In case of thick MOSFET, the degradation by hot carrier is confirmed using charge pumping current method and highly necessary to enhance overall device lifetime or circuit lifetime in upcoming nano-scale CMOS technology.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.840-845
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• 2017

In this paper, in order to investigate the lifetime of oil-paper insulation, specimens were artificially aged with thermal and electrical multiple stresses. Accelerated ageing factors and equivalent operating years for each aging temperatures were derived from results of tensile strengths for the aged paper specimens. Also, the evaluation for the multi-stress aged specimens were carried out through the measurement of impulse breakdown voltage at high temperature of $85^{\circ}C$. The lifetimes of the oil-paper insulations were calculated with the value of 66.7 for 1.0 mm thickness specimens and 69.7 for 1.25 mm thickness specimens throughout the analysis of impulse BD voltages using equivalent operating years, which means that dielectric strengths would not be severely decreased until the mechanical lifetime limit. Therefore, for the lifetime evaluation of the oil-paper insulation, thermal aging would be considered as a dominant factor whereas electrical degradation would be less effective.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.272-276
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• 2004

Great strides in organic light emitting device (OLED) technology have resulted in a number of commercial products. To continue this growth into large area displays, for example televisions, an understanding of the mechanisms that drive the OLED device efficiency and lifetime performance is critical. In this work, we consider maximizing the efficiency lifetime product based on phosphorescent OLED ($PHOLED^{TM}$) technology. We report green PHOLEDs with luminous efficiency of 82 cd/A, 5.7 V and 10,000 hours lifetime at 1,000 cd/$m^2$,red PHOLEDs with CIE of (0.67,0.33), 11 cd/A and 35,000 hours lifetime at 500 cd/$m^2$ and recent progress in blue demonstrating efficiencies of 18 cd/A at 200 cd/$m^2$.

• 한국세라믹학회지
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• 제34권9호
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• pp.927-934
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• 1997

Static and cyclic fatigue tests were carried out for alumina specimen to study the statistical analyses (normal, lognormal and Weibull distribution) of fatigue lifetime data and nominal initial crack length data. Fatigue lifetime data followed Weibull distribution better than normal or lognormal distribution, for the shape parameter of the notched specimen was larger than that of the unnotched specimen. The nominal initial crack length data obtained from fatigue lifetime followed the lognormal and Weibull distribution better than normal distribution, for the coefficient of variation of the unnotched specimen was larger than that of the notched specimen, and shape parameter of unnotched specimen was smaller than that of the notched specimen.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권1호
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• pp.37-45
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• 2009

Recently mechanical watt-hour meters are being replaced by electronic watt-hour meters. The replacement period of mechanical watt-hour meters is 7 years. This period is based on long term historical data. The replacement period of electronic watt-meters is also 7 years. This period is determined using the replacement period of mechanical watt-hour meters. However lifetime of mechanical watt-hour meters is different from the lifetime of electronic meters. In order to determine desirable replacement period of electronic watt-hour meters, accelerated life tests of major components in electronic watt-hour meters were performed. The test results showed that LCD was the component which had the shortest lifetime. In this paper, lifetime of electronic watt-hour meters manufactured by 3 company was estimated and life test standard for LCD was developed.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권2호
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• pp.35-42
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• 2003

This paper proposes a relative lifetime test method of MgO thin film. The suggested test conditions are 5$0^{\circ}C$, 400Torr, 20% over-voltage and 300KHz. The relative lifetime of MgO thin film is significantly affected by the MgO preparing conditions and Xe partial pressure. As result, the lifetime of the AC plasma display panel (PDP) is increased with an MgO thickness of 2000$\AA$ to 8000$\AA$ but is saturated over 5000$\AA$ (up to 9000 $\AA$). In addition, as Xe partial pressure increases, AC PDP lifetime increases.

• 한국진공학회지
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• 제5권2호
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• pp.161-168
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• 1996

For the improvement of microelectronic thin film interconnection materials, dielectric passivation effects on the electromigration phenomena were studied. Using Al-1%Si, various shaped patterns were fabricated and dielectric passivation layers of several structures were deposited on the $SiO_2$ layer. Lifetime of straight pattern showed 2~5 times longer than the other patterns that had various line width and area. It is believed that the flux divergence due to the structural inhomogeneity and so the current crowding effects shorten the lifetime of thin film interconnections. The lifetime of thin film interconnections seems to depend on both the passivation materials and the passivation thickness. PSG/$SiO_2$ dielectric passivation layers showed longer lifetime than $Si_3N_4$ dielectric passivation layers. This results from the PSG on $SiO_2$ layer reduces stress and from the improvement of resistance to the moisture and to the mobile ion such as sodium. This is also believed that the lifetime of thin film interconnections seems to depend on the passivation thickness in case of the same deposition materials.

• 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.

• International journal of advanced smart convergence
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• 제5권1호
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• pp.59-65
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• 2016

In this paper, we're compared network protocol which is network lifetime longer when using LEACH Protocol, SEP, and TEEN in a heterogeneous Wireless Sensor Network with a Large Sensor Area. Also, we propose a method of divided layer the wide-area sensor filed and transmitting a multi-hop to improve the network lifetime. And we're compared network protocol which is network lifetime more improved apply the proposed method to LEACH Protocol, SEP, and TEEN. We tried to compare results, TEEN showed the best network lifetime. Apply the proposed method to divided the sensor field, L-TEEN (Layered TEEN)'s network lifetime rates of improvement is highest.

• 한국통신학회논문지
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• 제35권7A호
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• pp.660-668
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• 2010

에너지 자원이 제한된 네트워크에서는 채널 상태 정보와 남은 에너지 정보를 기반으로 에너지자원을 각 유저들에게 최적으로 할당함으로써 네트워크의 수명을 향상시킬 수 있다. 본 논문에서는 전송 용량을 만족시키면서 네트워크의 수명을 최대화하도록 전송에 참여하는 중계기를 선택하고 전송 전력을 할당하는 기법을 제안한다. 모의 실험을 통해 제안된 기법이 기존 기법에 비해서 수명을 증가시키는 것을 보인다.