• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
• /
• pp.342-343
• /
• 2012

We studied the Drain-Induced-Barrier-Lowering (DIBL) effect by different drain engineering. One other drain engineering is symmetric source-drain n-channel MOSFETs (SSD NMOSs), the other drain engineering is asymmetric source-drain n-channel MOSFETs (ASD NMOSs). Devices were fabricated using state of art 40 nm dynamic-random-access-memory (DRAM) technology. These devices have different modes which are deep drain junction mode in SSD NMOSs and shallow drain junction mode in ASD NMOSs. The shallow drain junction mode means that drain is only Lightly-Doped-Drain (LDD). The deep drain junction mode means that drain have same process with source. The threshold voltage gap between low drain voltage ($V_D$=0.05V) and high drain voltage ($V_D$=3V) is 0.088V in shallow drain junction mode and 0.615V in deep drain junction mode at $0.16{\mu}m$ of gate length. The DIBL coefficients are 26.5 mV/V in shallow drain junction mode and 205.7 mV/V in deep drain junction mode. These experimental results present that DIBL effect is higher in deep drain junction mode than shallow drain junction mode. These results are caused that ASD NMOSs have low drain doping level and low lateral electric field.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2010년도 춘계 학술발표회
• /
• pp.1256-1263
• /
• 2010

Suction Drain Method is soft ground improvement technique, in which a vacuum pressure can be directly applied to the Vertical Drain Board to promote consolidation and strengthening the soft ground. This method does not require a surcharge load, different to embankment or Preloading Method. In this study, ground improvement efficiency of suction drain method was estimated when duplex loading pressure with vacuum and pressure. During suction drain method process, surface settlement and pore pressure were monitored, and cone resistance test as well as water content were also measured after the completion of Suction Drain Method treatment.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
• /
• pp.1126-1131
• /
• 2009

Suction Drain Method is soft ground improvement technique, in which a vacuum pressure can be directly applied to the Vertical Drain Board to promote consolidation and strengthening the soft ground. This method does not require a surcharge load, different to embankment or vertical drain method. In this study, Using Suction-CAIN program, which optimize th Suction Drain method, estimate validity Suction Drain method on deep soft ground

• 한국환경복원기술학회지
• /
• 제9권1호
• /
• pp.1-13
• /
• 2006

The recent environmental protection issue has diminished the supply of sand for soft ground improvements so much that the prices of sand have shown a sudden rise. Plastic material is one of substitutes for sand material, but plastic is nonperishable and doubtable if it has potential environmental hormone disrupting substances. Moderate-priced natural fiber drain board made with coconut coir and jute filter are in the spotlight recently as an alternative material for sand and plastic drain board etc. Natural fiber drain has not only competitive price but also a characteristic of assimilation into the soils after finishing of its own function. Discharge capacity of the fiber drain board evaluated by triaxial type discharge capacity test was relatively lower than that of plastic drain board. Nevertheless, settlement and pore pressure dissipation behaviors of the fiber drain board and the plastic drain board which were installed in the clayey soil during the composite discharge capacity test were almost similar. It was also found that biodegradation of the fiber drain board was in progress until 18 month after installation in the clayey soil, but they had still enough engineering properties to use at field.

• 대한전자공학회논문지SD
• /
• 제38권6호
• /
• pp.390-397
• /
• 2001

GIDL(Gate-Induced Drain-Leakage)을 줄일 수 있는 새로운 구조의 ESD(Elevated Source Drain) MOSFET을 제안하고 분석하였다. 제안된 구조는 SDE(Source Drain Extension) 영역이 들려진 형태를 갖고 있어서 SDE 임플란트시 매우 낮은 에너지 이온주입으로 인한 저활성화(low-activation) 효과를 방지 할 수 있다. 제안된 구조는 건식 식각 및 LAT(Large-Angle-Tilted) 이온주입 방법을 사용하여 소오스/드레인 구조를 결정한다. 기존의 LDD MOSFET과의 비교 시뮬레이션 결과, 제안된 ESD MOSFET은 전류 구동능력은 가장 크면서 GIDL 및 DIBL(Drain Induced Barrier Lowering) 값은 효과적으로 감소시킬 수 있음을 확인하였다. GIDL 전류가 감소되는 원인으로는 최대 전계의 위치가 드레인 쪽으로 이동함에 따라 최대 밴드간 터널링이 일어나는 곳에서의 최대 전계값이 감소되기 때문이다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 하계학술대회 논문집 C
• /
• pp.1357-1359
• /
• 2001

0.2${\mu}m$ 이하의 최소 선폭을 가지는 소자를 구현할 때 drain induced barrier lowering (DIBL)이나 hot electron effect와 같은 short channel effect (SCE)가 나타나며 이로 인하여 소자의 신뢰성이 악화되기도 한다. 이를 개선하기 위한 방법 중 하나가 silicon selective epitaxial growth (SEG)를 이용한 elevated source/drain (ESD) 구조이다. 본 연 구에서는 silicon selective epitaxial growth를 이용하여 elevated source/drain 구조를 갖는 MOSFET 소자와 일반적인 MOSFET 구조를 갖는 소자와의 차이를 elevated source/drain의 높이 변화에 따른 전류 전압 특성을 이용하여 비교, 분석하였으며 그 결과 elevated source/drain 구조가 short channel effect를 감소시킴을 확인할 수 있었다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 춘계 학술발표회
• /
• pp.692-701
• /
• 2009

The use of vertical drain method to improve the soft soil ground has been continuously increased in Korea such as Busan New Port, Saemangeum reclamation project and so on in Korea. Especially PBD(Plastic Board Drain), one of the vertical drain, has been widely used due to the economic feasibility, construction compatibility and quality control. However in case of using PBD, discharge capacity reduction caused by creep deformation of the PBD filter, bending, kinking and so on can be occurred. Therefore the purpose of this study is to solve these problems by developing Deformation-Compatible Vertical Drain, DCVD which allows to deform with consolidation settlement without bending and kinking of vertical drain. In order to investigate the performance of DCVD developed in this study, discharge capacity test, centrifuge model test and complex discharge capacity test for both PBD and DCVD are performed and the results are compared.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제9권2호
• /
• pp.110-116
• /
• 2009

The prominent advantages of Dual Material Surrounding Gate (DMSG) MOSFETs are higher speed, higher current drive, lower power consumption, enhanced short channel immunity and increased packing density, thus promising new opportunities for scaling and advanced design. In this Paper, we present Transconductance-to-drain current ratio and electric field distribution model for dual material surrounding gate (DMSGTs) MOSFETs. Transconductance-to-drain current ratio is a better criterion to access the performance of a device than the transconductance. This proposed model offers the basic designing guidance for dual material surrounding gate MOSFETs.

• 한국지반신소재학회논문집
• /
• 제9권3호
• /
• pp.67-75
• /
• 2010

본 연구에서는 생분해성 수지를 이용한 연직배수재에 대해 다양한 성능 평가방법을 적용하여 생분해성 플라스틱배수재의 공학적 특성을 분석하였다. 생분해성 플라스틱으로 제작한 연직배수재는 기존 합성수지 연직배수재에 비해 낮은 인장변형률을 가지며 상대적으로 낮은 인장강도를 갖지만, 연직배수재로서 가져야 할 최소한의 인장강도는 발휘하는 것으로 나타났다. 생분해성 플라스틱으로 제작한 필터는 투수성이 좋고 유효구멍크기가 작아 필터의 성능으로 매우 적합한 것으로 나타났다. 또한 생분해성플라스틱 배수재의 통수능은 필터의 강성을 개선하는 경우 국내 시방기준에도 만족할 수 있는 성능을 갖는 것으로 나타났다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2010년도 추계 학술발표회 2차
• /
• pp.141-146
• /
• 2010

To investigate the effect of drainage spacing and smear on the rate of consolidation, a large consolidation chamber and mandrel insertion device were developed. After the occurrence of smear by installation of sand drain, model ground was consolidated in either overconsolidated or normally consolidated state. As smear effect increases and thus drain spacing decreases, total settlement increase in overconsolidated state but has no effect in normally consolidated state. Efficiency of vertical drain decreases and consequently consolidation time increases in all tests as smear effect becomes significant.