• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.193-196
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• 2002

This paper presents the improvement of the boron penetration and the reverse short channel effect (RSCE) in the 130nm W/WNx/Poly-Si dual gate PMOSFET for a high performance embedded DRAM. In order to suppress the boron penetration, we studied a range in the process heat budget. It has shown that the process heat budget reduction results in suppression of the boron penetration. To suppress the RSCE, we experimented with the halo (large tilt implantation of the same type of impurities as those in the device well) implant condition near the source/drain. It has shown that the low angle of the halo implant results in the suppression of the RSCE. The experiment was supported from two-dimensional(2-D) simulation, TSUPREM4 and MEDICI.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.24-29
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• 2003

This research was performed to investigate the diffusivity of borate rods in radiata pine (Pinus radiata D. Don) conditioned to 40 percent moisture content (MC). The deepest penetration of boron were observed in the longitudinal direction, followed by the radial and the tangential directions. The boron loading on the wood face adjacent to the borate rod tended to increase with diffusion time in all directions. To mathematically quantify boron diffusion, the diffusion coefficient of boron was determined using Boltzmann's transformation by assuming that it was a function of concentration only. The values of the longitudinal diffusion coefficients were between 1.3×10^-8 cm²/sec and 9.2×10^-8 cm²/sec. The radial diffusion coefficients were between 1.4×10^-8 cm²/sec and 9.5×10^-8 cm²/sec, and the tangential diffusion coefficients were between 5.2×10^-9 cm²/sec and 1.3×10^-8 cm²/sec. The differences of diffusion coefficients between the longitudinal direction and the radial direction were slight, although their concentration profiles were markedly different. This indicates that the amount of boron loading on the wood face adjacent the borate rod is one of the most important factor for boron penetration in wood with low MC.

• Journal of information and communication convergence engineering
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• 제5권2호
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• pp.109-111
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• 2007

In this paper, MOS devices with ultrathin gate dielectrics (5.5 nm) are characterized and compared with those with conventional oxides particularly for nanoscale CMOS applications. Nitrogen concentrations and profiles in the nitride gate dielectrics were obtained that will play an important role in improving both hot-carrier lifetime and resistance to boron penetration. This approach seems very useful for future nanoscale CMOS device applications.

• 대한방사성의약품학회지
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• 제7권1호
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• pp.3-10
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• 2021

For successful boron neutron caputre therapy, it is essential to develop a boron drug with a selective accumulation capacity for tumors. In particular, in order to apply boron neutron caputre therapy to brain tumors, drugs with good blood-brain barrier penetration are required. In this study, two low-molecular-weight boron compounds were introduced as brain tumor boron neutron caputre therapy drugs, and their physical and biological efficacy were evaluated. Among them, B2 showed good blood-brain barrier permeability and a high brain/blood ratio. From these results, it is expected that B2 can be used as a useful boron drug for boron neutron caputre therapy in brain tumors.

• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.513-526
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• 2020

The existing preservation methods are difficult to be applied to a large dimension log which is needed for making traditional wooden ship 'Jalur' in Riau Province. Novel techniques to provide the use of readily available species to replace traditional species alternative were investigated. These included infusion and a combination of injection and bandage-wrapping methods for preserving living trees of Balam (Macaranga conifera (Rchb.f. & Zoll.) Müll.Arg.) and Bintangor (Calophyllum soulattri Burm.f.). Water-based boron compounds were applied as wood preservatives. In total, 18 discs from the bottom, middle, and top of four trees and two controls were used. Trees undergoing treatment were also used to see how wood anatomical structure might affect the boron penetration. The overall aim was to identify the best method for use in Jalur manufacturing. The results showed that in infused Balam tree where the hose position for the preservative intake was deep (10-15 cm from the bark), no boron compound was observed in the outer sapwood. Combination of injection and bandage-wrapping method gave higher percentage of boron penetration at bottom and middle of Balam tree. However, infused Bintangor showed 100% boron penetration. The larger vessel diameter, the absence of tyloses, and the simple perforation plates in Bintangor wood were likely to have contributed to the higher penetration of boron. The combination of bandage-wrapping and infusion, or alternatively by infusing the living trees close to the bark, and at as low as position in the stem gives better protection when treatments are applied to living trees.

• 대한기계학회논문집A
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• 제39권1호
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• pp.89-94
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• 2015

본 연구의 목적은 열처리 전 후의 보론강 레이저 용접성을 비교하는 것이다. 일반적으로 보론강이 핫스탬핑 공정에 사용되고 있으며, 핫스탬핑 공정은 강판을 오스테나이트 온도까지 가열한 후 성형과 동시에 냉각하는 방법이다. 열처리후 보론강은 1500 MPa 이상의 고강도를 가진다. 따라서 본 연구에서는 보론강 및 핫스탬핑강의 레이저 용접성을 조사한 후 비교하였다. CW 디스크 레이저를 이용하여 레이저 출력 및 용접속도를 변화시켜가며 맞대기 및 겹치기 용접을 실시하였다. 맞대기 용접 결과, 핫스탬핑강에서 완전 용입을 얻을 수 있는 임계냉각속도가 보론강보다 낮았으며, 겹치기 용접결과 완전 관통이 일어난 용접 조건에서는 접합부 폭은 용접속도와 관계없이 거의 유사하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권2호
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• pp.103-110
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• 2001

Gate oxide scaling for sub-l00nm CMOS devices has been studied. Issues on the gate oxide scaling are reviewed, which are boron penetration, reliability, and direct tunneling leakage currents. Reliability of Sub-2.0nm oxides and the device performance degradation due to boron penetration are investigated. Especially, the effect of gate leakage currents on the transistor characteristics is studied. As a result, it is proposed that thinner oxides than previous expectations may be usable as scaling proceeds. Based on the gate oxide thickness optimization process we have established, high performance CMOS transistors of $L_{gate}=70nm$ and $T_{ox}=1.4nm$ were fabricated, which showed excellent current drives of $860\mu\textrm{A}/\mu\textrm{m}$ (NMOS) and $350\mu\textrm{A}/\mu\textrm{m}$ (PMOS) at $I_{off}=10\mu\textrm{A}/\mu\textrm{m}$ and $V_dd=1.2V$, and CV/I of 1.60ps (NMOS) and 3.32ps(PMOS).

• Computers and Concrete
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• 제15권5호
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• pp.833-845
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• 2015

In the world total boron reserve rating, Turkey is taken place on the first rank, meeting the demand of refined mineral and main boron chemicals. Development of the new boron products and production technologies, spreading the using area of the boron are the study topics which must be finically discussed. In this study, with the help of colemanite taken in ratio as (0%, 7.5%, 12.5%, and 17.5%) by being mixed by the cement, surfaces of the pumice aggregates have been covered. Permeability of the samples has been investigated by producing lightweight concrete with 400 dose with the help of aggregates covered with colemanite. For this, the experiments of water absorption, capillary water absorption, depth of penetration of water under pressure and rapid chloride permeability have been performed. In addition, analyses of the thin section of covered and uncovered pumice aggregates and SEM (Scanning Electron Microscope) have been investigated. When the control samples produced with the covered aggregates and concretes produced with colemanite covered aggregates are compared each other, it has been determined that special lightweight concretes whose values of capillary water absorption experiment, depth of penetration of water under pressure experiment and rapid chloride permeability are low can be produced.

• 한국재료학회지
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• 제1권3호
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• pp.125-131
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• 1991

pMOS소자의 $p^{+}$게이트 전극으로 다결정실리콘과 비정질실리콘을 사용하여 고온의 열처리 공정에 따른 붕소이온의 침투현상을 high frequency C-V plot, Constant Current Stress Test(CCST), Secondary Ion Mass Spectroscopy(SIMS) 및 Transmission Electron Microscopy(TEM)를 이용하여 비교하였다. C-V plot분석 결과 비정질실리콘 게이트가 다결정실리콘 게이트에 비해 flatband전압의 변화가 작게 나타났으며, 게이트 산화막의 절연파괴 전하밀도에서는 60~80% 정도 향상된 값을 나타내었다. 비정질실리콘 게이트는 증착시 비정질로 형성되는 구조로 인한 얇은 이온주입 깊이와 열처리 공정시 다결정실리콘에 비교하여 크게 성장하는 입자 크기 때문에 붕소이온의 침투 경로가 되는 grain boundary를 감소시켜 붕소이온 확산을 억제한 것으로 생각된다. Electron trapping rate와 flatband 전압 변화와의 관계에 대하여 고찰하였다.

• Nuclear Engineering and Technology
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• 제53권2호
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• pp.626-636
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• 2021

Boron-neutron capture therapy (BNCT) is a cancer treatment method that exploits the high neutron reactivity of boron. Monitoring the prompt gamma rays (PGs) produced during neutron irradiation is essential for ensuring the accuracy and safety of BNCT. We investigate the imaging of PGs produced by the boron-neutron capture reaction through Monte Carlo simulations of a gamma camera with a SrI₂ scintillator and parallel-hole collimator. GAGG scintillator is also used for a comparison. The simulations allow the shapes of the energy spectra, which exhibit a peak at 478 keV, to be determined along with the PG images from a boron-water phantom. It is found that increasing the size of the water phantom results in a greater number of image counts and lower contrast. Additionally, a higher septal penetration ratio results in poorer image quality, and a SrI₂ scintillator results in higher image contrast. Thus, we can simulate the BNCT process and obtain an energy spectrum with a reasonable shape, as well as suitable PG images. Both GAGG and SrI₂ crystals are suitable for PG imaging during BNCT. However, for higher imaging quality, SrI₂ and a collimator with a lower septal penetration ratio should be utilized.