• E2M - 전기 전자와 첨단 소재
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• 제8권1호
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• pp.56-63
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• 1995

MESFETs of the Ti/Au and Ti/Pd/Au gate were fabricated on n-type GaAs. Interdiffusion at Schottky interfaces, Schottky contact properties, and MESFET characteristics with heat treatment were investigated. Ti of Ti/Au contact and Pd of Ti/Pd/Au contact acted as a barrier metal against interdiffusion of Au at >$220^{\circ}C$. Pd of Ti/Pd/Au contact acted as a barrier metal even at >$360^{\circ}C$, however, Ti of Ti/Au contact promoted interdiffusion of Au instead of role of barrier metal. As the heat treatment temperature increases, in the case of both contact, saturated drain current and pinch off voltage decreased, open channel resistance increased, and degree of parameter variation in Ti/Au gate was higher than in Ti/Pd/Au gate at >$360^{\circ}C$ Schottky barrier height of Ti/Au and Ti/Pd/Au contacts was 0.69eV and 0.68eV in the as-deposited state, respectively, and Fermi level was pinned in the vicinity of 1/2Eg. As the heat treatment temperature increases, barrier height of Ti/Pd/Au contact increased, however, decreased at >$360^{\circ}C$ in the case of Ti/Au contact. Ideality factor of Ti/Au contact was nearly constant regardless of heat treatment, however, increased at >$360^{\circ}C$ in the case of Ti/Au contact. From the results above, Ti/Pd/Au was stable gate metal than Ti/Au.

• 동력기계공학회지
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• 제17권5호
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• pp.44-51
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• 2013

This paper proposes and analyzes recycling of optical phonons emitted by nonradiative decay, which is a major thermal management concern for high-power light emitting diodes (LED), by introducing an integrated, heterogeneous barrier cooling layer. The cooling is proportional to the number of phonons absorbed per electron overcoming the potential barrier, while the multi-phonon absorption rate is inversely proportional to this number. We address the theoretical treatment of photon-electron-phonon interaction/transport kinetics for optimal number of phonons (i.e., barrier height). We consider a GaN/InGaN LED with a metal/AlGaAs/GaAs/metal potential barrier and discuss the energy conversion rates. We find that significant amount of heat can be recycled by the barrier transition cooling layer.

• 한국자기학회지
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• 제15권2호
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• pp.133-136
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• 2005

In the case of contacts between semiconductor and metal in semiconductor devices, they tend to be unstable because of thermal budget. To prevent these problems we deposited W-C-N diffusion barrier for preventing the interdiffusion between metal and semiconductor. The thickness of the barrier is $1,000{\AA}$ and the pressure is 3 mTorr during the deposition. In this work we coated LSMO (CMR material) on W-C-N diffusion barrier and then we studied the interface effects between LSMO layer and W-C-N diffusion barrier. We got results that the magnetic characteristics of LSMO thin film are still maintained after annealing at $800^{\circ}C$ for 3 hr because W-C-N thin diffusion barrier was prevented the diffusion of oxygen between LSMO and Si substrate.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1252-1254
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• 2005

Recently, PDP barrier ribs require the formation of complex structure so that they are usually formed by etching method. For producing the fine ribs structure, during the etching process the metal ions of matrix (glass) of barrier materials should be understood on the etching mechanism with etching condition. We analyzed the quantity of Pb, Si, and B ions from the etch solution as a function of etching time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 반도체재료
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• pp.54-56
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• 2001

The $SiH_4$ soak step is widely used during the CVD Tungsten(W) plug deposition process on the Ti/TiN barrier metal to prevent the $WF_6$ attack to the underlayer metal. We tried to reduce or skip the time of $SiH_4$ soak process to optimize W-plug deposition process on Via. The electrical characteristics including Via resistance and the structure of W film are affected according to $SiH_4$ soak time. The elimination possibility of $SiH_4$ soak process was confirmed in the case of that the CVD W film grows on the stable Ti/TiN underlayer.

• 한국전기전자재료학회논문지
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• 제16권7호
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• pp.569-572
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• 2003

In this study, we evaluated the dilute HF cleaning to reduce residual defects made by metal CMP process. The purpose of this test is to observe the existence of barrier metal damage during DHF cleaning on condition that it should not affect metal thin film reliability, so we will get rid of slurry residual particles as a main defect of the metal CMP process for the better yield. In-line defect data showed us that slurry residual particles were removed by DHF application. The HF rinse significantly reduced metal contamination levels and surface roughness. The best effect by additional oxide loss was discovered when Dilute HF condition is 10".

• ETRI Journal
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• 제24권6호
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• pp.455-461
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• 2002

This paper reports on estimating the Schottky barrier height of small contacts using a thermionic-field emission model. Our results indicate that the logarithmic plot of the current as a function of bias voltage across the Schottky diode gives a linear relationship, while the plot as a function of the total applied voltage across a metal-silicon contact gives a parabolic relationship. The Schottky barrier height is extracted from the slope of the linear line resulting from the logarithmic plot of current versus bias voltage across the Schottky diode. The result reveals that the barrier height decreases from 0.6 eV to 0.49 eV when the thickness of the barrier metal is increased from 500 ${\AA}$ to 900 ${\AA}$. The extracted impurity concentration at the contact interface changes slightly with different Ti thicknesses with its maximum value at about $2.9{\times}10^{20}\;cm^{-3}$, which agrees well with the results from secondary ion mass spectroscopy (SIMS) measurements.

• 태양에너지
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• 제17권1호
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• pp.59-66
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• 1997

개방전압과 단락전류와 같은 태양전지 출력변수들은 접합깊이, 도핑농도, 금속접합 및 태양전지구조에 의한 변수들이다. 태양전지 설계의 중요한 요소로서 인이 도핑된 에미터와 금속사이의 금속접합은 일함수 차이가 작아 낮은 직렬저항을 가져야 한다. PESC 태양전지는 금속 접합장벽 전극으로 티타늄을 사용한다. 새로운 접합장벽 전극물질로 티타늄과 일함수가 비슷하지만 전기전도도가 우수한 크롬은 금속 접합장벽 전극으로 유망한 금속이다. 티타늄은 일함수 차가 작지만, 접합장벽으로 크롬은 태양전지 제조시 티타늄보다 우수한 전기적 특성들을 갖는다. 본 논문에서는 실리콘 태양전지의 접합장벽 금속전극의 특성을 비교 분석하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제7권2호
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• pp.82-87
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• 2007

The electrical properties of metallic junction diodes and metallic source/drain (S/D) Schottky barrier metal-oxide-semiconductor field-effect transistor (SB-MOSFET) were simulated. By using the abrupt metallic junction at the S/D region, the short-channel effects in nano-scaled MOSFET devices can be effectively suppressed. Particularly, the effects of trap states at the metal-silicide/silicon interface of S/D junction were simulated by taking into account the tail distributions and the Gaussian distributions at the silicon band edge and at the silicon midgap, respectively. As a result of device simulation, the reduction of interfacial trap states with Gaussian distribution is more important than that of interfacial trap states with tail distribution for improving the metallic junction diodes and SB-MOSFET. It is that a forming gas annealing after silicide formation significantly improved the electrical properties of metallic junction devices.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2265-2267
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• 2005

We present detailed studies of externally applicable UHF PD sensors for a metal covered epoxy barrier with a small opening of epoxy injection-hole. The sensors were attached at the surface of injection hole of a metal covered epoxy barrier. 3-Dimensional electro magnetic simulations were performed to analyze electric-field distribution of the GIS and epoxy barrier with injection hole. Sensor structures were designed and analyzed using the 3-D EM simulator then fabricated for experimental verification. Sensor performance was measured in terms of spectral response and detected peak power. Real scale GIS and epoxy barriers were used to test and measure various aspect of performance of the sensors.