• JSTS:Journal of Semiconductor Technology and Science
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• 제7권4호
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• pp.287-298
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• 2007

A two-dimensional treatment of the potential distribution under the depletion approximation is presented for poly-crystalline silicon thin film transistors. Green's function approach is adopted to solve the two-dimensional Poisson's equation. The solution for the potential distribution is derived using Neumann's boundary condition at the silicon-silicon di-oxide interface. The developed model gives insight into device behavior due to the effects of traps and grain-boundaries. Also short-channel effects and drain induced barrier lowering effects are incorporated in the model. The potential distribution and electric field variation with various device parameters is shown. An analysis of threshold voltage is also presented. The results obtained show good agreement with simulated results and numerical modeling based on the finite difference method, thus demonstrating the validity of our model.

• 한국전기전자재료학회논문지
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• 제32권2호
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• pp.104-109
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• 2019

An analytical threshold voltage model is proposed to analyze the threshold voltage roll-off and drain-induced barrier lowering (DIBL) for a junction-based double-gate (JBDG) MOSFET and a junction-less double-gate (JLDG) MOSFET. We used the series-type potential distribution function derived from the Poisson equation, and observed that it is sufficient to use n=1 due to the drastic decrease in eigenvalues when increasing the n of the series-type potential function. The threshold voltage derived from this threshold voltage model was in good agreement with the result of TCAD simulation. The threshold voltage roll-off of the JBDG MOSFET was about 57% better than that of the JLDG MOSFET for a channel length of 25 nm, channel thickness of 10 nm, and oxide thickness of 2 nm. The DIBL of the JBDG MOSFET was about 12% better than that of the JLDG MOSFET, at a gate metal work-function of 5 eV. It was also found that decreasing the work-function of the gate metal significantly reduces the DIBL.

• 한국전기전자재료학회논문지
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• 제24권4호
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• pp.271-275
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• 2011

In this paper, thermal stability of palladium germanide (Pd germanide) is analyzed for high performance Schottky barrier germanium metal oxide semiconductor field effect transistors (SB Ge-MOSFETs). Pd germanide Schottky barrier diodes were fabricated on n-type Ge-on-Si substrates and the formed Pd germanide shows thermal immunity up to $450^{\circ}C$. The barrier height of Pd germanide is also characterized using two methods. It is shown that Pd germanide contact has electron Schottky barrier height of 0.569~0.631 eV and work function of 4.699~4.761 eV, respectively. Pd germanide is promising for the nanoscale Schottky barrier Ge channel MOSFETs.

• 한국정보통신학회논문지
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• 제17권1호
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• pp.145-150
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• 2013

본 연구에서는 차세대 나노소자인 DGMOSFET에 대하여 문턱전압 이하영역에서 발생하는 단채널 효과 중 문턱전압 및 드레인유도장벽감소의 변화를 스켈링 이론에 따라 분석하였다. 포아송방정식의 분석학적 해를 구하기 위하여 전하분포함수에 대하여 가우시안 함수를 사용함으로써 보다 실험값에 가깝게 해석하였으며 이때 가우시안 함수의 변수인 이온주입범위 및 분포편차 그리고 소자 파라미터인 채널의 두께, 도핑농도 등에 대하여 문턱전압 특성의 변화를 관찰하였다. 본 연구의 모델에 대한 타당성은 이미 기존에 발표된 논문에서 입증하였으며 본 연구에서는 이 모델을 이용하여 문턱전압이하 특성을 분석하였다. 분석결과 스켈링 이론 적용 시 문턱전압 및 드레인유도장벽감소 현상이 변화하였으며 변화 정도는 소자파라미터에 따라 변화한다는 것을 관찰하였다.

• 한국정보통신학회논문지
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• 제21권8호
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• pp.1465-1470
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• 2017

기존의 MOSFET에서는 반전층보다 항상 실리콘 두께가 크기 때문에 드레인유도 장벽감소가 실리콘 두께에 관계없이 산화막 두께 및 채널길이의 함수로 표현되었다. 그러나 10 nm 이하 저도핑 이중게이트 구조에서는 실리콘 두께 전체가 공핍층이 형성되기 때문에 기존의 SPICE 모델을 사용할 수 없게 되었다. 그러므로 이중게이트 MOSFET에 대한 새로운 SPICE 용 드레인유도 장벽감소 모델을 제시하고자 한다. 이를 분석하기 위하여 전위분포와 WKB 근사를 이용하여 열방사 및 터널링 전류를 구하였다. 결과적으로 드레인유도 장벽감소는 상하단 산화막 두께의 합 그리고 실리콘 두께의 2승에 비례하며 채널길이의 3승에 반비례한다는 것을 알 수 있었다. 특히 SPICE 파라미터인 정적 궤환계수가 1과 2사이에서 사용할 수 있어 합당한 파라미터로써 사용할 수 있었다.

• KSBB Journal
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• 제14권1호
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• pp.1-8
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• 1999

It confirmed the facilitated diffusion of $Na^+$ of frog bladder membrane which is a tissue membrane. The mechanism was explained in $Na^+$ channel model and its referred to the $Na^+$ channel obstruction ingredient which was contained in the reference to the $Na^+$ channel obstruction ingredient and son on, e.g., seaweed, shellfish, pufferfish, phytoplankton and chinese drug. Also, it introduces the result which studied from the barrier point of the application of the tissue biosensor to the trade friction on Korea or Japan pufferfish and the marine environment in the one with high dependance. It was possible for the poison quantity of small amount pufferfish toxin (TTX), paralytic shellfish poisoning (PSP) to be measured and also to measure poison quantity in the cultivation poisonous toxin phytoplankton individual. In future, as for this tissue biosensor, it expects that it is possible to contribute widely until environment watch and also monitoring to the scene.

• 한국전기전자재료학회논문지
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• 제22권11호
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• pp.905-909
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• 2009

The new Junction Field Effect Transistors (JFETs) with Silicon-germanium (SiGe) layers is investigated. This structure uses SiGe layer to prevent out diffusion of boron in the channel region. In this paper, we report electrical properties of SiGe JFET measured under various design parameters influencing the performance of the device. Simulation results show that out diffusion of boron is reduced by the insertion SiGe layers. Because the SiGe layer acts as a barrier to prevent the spread of boron. This proposed JFET, regardless of changes in fabrication processes, accurate and stable cutoff voltage can be controlled. It is easy to maintain certain electrical characteristics to improve the yield of JFET devices.

• 대한한의학원전학회지
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• 제18권4호통권31호
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• pp.145-154
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• 2005

The SangHanIlJeGeum(傷寒-提金) explain the six channel of disease. The Greater Yang controls the construction and defence, and governs the exterior of the body, which serves as the body's external barrier. Accordingly, many of the signs associated with greater yang appear in the early stages of disease. The essential features of greater yang disease are a pulse that is floating, headache, stiffness and pain of the head and nape, heateffusion, and aversion to cold. The main feature of Yang brightness disease is yang hyperactivity and heat exuberance. An evil can directly enter the yang brightness channel from the exterior, but it usually passes into the channel from the greater yang. Yang brightness disease is generally characterized by generalized heat effusion, spontaneous sweating, aversion not to cold but to heat, and a pulse that is large. Distinction is made between a heat patter and a repletion pattern.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.342-344
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• 2005

We have simulated a symmetric dual-gate TFT which has triple floating n+ channel to improve the on-current of the dual-gate TFT. We achieved a low hole concentration at the source and channel junction causes the improvement the potential barrier so that we observed the reduction of the kink-effect. In this paper, we observed the reduction of the kink-effect compared with the conventional single-gate TFT and the improvement of the on-current compared with the conventional dual-gate TFT.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.333-336
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• 2008

U-Channel Bridge is effective bridge type, because its edge beam performs role of barrier and enables to reduce additional dead loads. Nevertheless, there is possibility of bridge collapse under impact load due to car crash. Also, edge beam must have ability to induce safe driving and prevent falling accidents. Therefore, this study carries out analysis of behavior of edge beam and slab and evaluation of structural stability under impact loads, based on Korean Highway Bridge Design Specifications and AASHTO LRFD Bridge Design Specification. According to analysis result, the maximum stress of edge beam and slab satisfies specification of allowable stress.