• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.335-336
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.105-106
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• 2008

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.163-166
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• 2004

모바일향 90nm DRAM을 개발하기 위하여 비대칭 채널 구조를 갖는 Recess Channel Array Transistor (RCAT)로 cell transistor를 구현하였다. DRAM cell transistor에서 junction leakage current 증가는 DRAM retention time 열화에 심각한 영향을 미치는 요인으로 알려져 있으며, DRAM의 minimum feature size가 점점 감소함에 따라 short channel effect의 영향으로 junction leakage current는 더욱 더 증가하게 된다. 본 실험에서는 short channel effect의 영향에 의한 junction leakage current를 감소시키기 위하여 Recess Channel Array Transistor를 도입하였고, cell transistor의 채널 영역을 비대칭으로 형성하여 data retention time을 증가시켰다. 비대칭 채널 구조을 이용하여 Recess Channel Array Transistor를 구현한 결과, sub-threshold 특성과 문턱전압, Body effect, 그리고, GIDL 특성에는 큰 유의차가 보이지 않았고, I-V특성인 드레인 포화전류(IDS)는 대칭 채널 구조인 transistor 대비 24.8% 정도 증가하였다. 그리고, data retention time은 2배 정도 증가하였다. 본 실험에서 얻은 결과는 향후 저전압 DRAM 개발과 응용에 상당한 기여를 할 것으로 기대된다.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.3
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• pp.387-400
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• 2017

A new junction-splitting based SAR ADC with a redundant searching capacitor array structure in $0.13{\mu}m$ CMOS process to alleviate capacitor mismatch effects, is presented. The normalized average power has a factor of 0.35 to the conventional SAR ADC at 10-bit conversion accuracy. Statistical experiments show the number of missing codes resulting from the mismatch reduces by 95% for 3% unit-capacitor mismatch ratio, while keeping the conversion energy to that of the conventional JS capacitor array.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.1
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• pp.142-149
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• 1999

In this paper, Aperture-coupled microstrip array antenna was designed and manufactured for satellite communication at Ka-Band. We analyzed a microstrip radiation element and designed power divider using $\lambda$g/4 transformer and T-junction power divider. A manufactured Aperture-coupled $2\times2$ microstrip array antenna has a resonant frequency of 20 GHz. The experimental results are as followings : resonant frequency of 19.62 GHz, VSWR 1.0692, return loss -29.61 dB, Bandwidth 1.76 GHz and -3 dB beamwidth $42^{\circ}$.

• Progress in Superconductivity
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• v.3 no.1
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• pp.49-55
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• 2001

Josephson junction arrays were fabricated by DC magnetron sputtering, self-aligning and reactive ion etching technique. The Al native oxide, formed by thermal oxidation, was used as the tunneling barrier of Nb/$Al-A1_2$$O_3$Nb trilayer. The arrays have 2,000 Josephson junctions with the area of $14\mu\textrm{m}$ $\times$ $46\mu\textrm{m}$. The gap voltages were in the range of 2.5 ~2.6 mV and the spread of critical current was $\pm$11~14%. When operated at 70~94 ㎓, the arrays generated zero-crossing steps up to 2.1~2.4 V. To improve transmission of microwave power and prevent diffusion of oxygen into Nb ground-plane while depositing $SiO_2$dielectric, we applied a plasma nitridation process to the Nb ground-plane. The microwave power was well propagated in Josephson junction arrays with nitridation. The difference in microwave transmission 7an be interpreted by the surface impedance change depending on nitridation.

• 한국초전도학회:학술대회논문집
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• v.16
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• pp.39-39
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• 2006

• Transactions on Electrical and Electronic Materials
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• v.17 no.6
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• pp.359-362
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• 2016

In the PV (Photovoltaic) power system, a junction box collects the DC voltage generated from the PV module and transfers it to the PCS (power conditioning system). The junction box prevents damage caused by the voltage difference between the serially connected PV modules and provides convenience while repairing or inspecting the PV array. In addition, the junction box uses the diode to protect modules from the inverse current when the PV power system and electric power system are connected for use. However, by using the reverse blocking diode, heat is generated within the junction box while generating electric power, which decreases the generating efficiency, and causes short circuit and electric leakage. In this research, based on the purpose of improving the performance of the PV module by decreasing the heat generation within the junction box, a junction box with a built-in bypass circuit was designed/manufactured so that a certain capacity of current generated from the PV module does not run through the reverse blocking diode. The manufactured junction box was used to compare the electric power and heating power generated when the circuit was in the bypass/non-bypass modes. It was confirmed that the electric power loss and heat generation indicated a decrease when the circuit was in the bypass mode.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.307-310
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• 2005

To get the spatial feature of arterial pulse, we designed spatial pulse diagnostic apparatus (SPDA) using a 2-dimensional magnetoresistive sensor array. The magnetic field distribution fur magnet may was simulated using finite element method. We recognized that the field distribution of parallel magnet mays was more sensitive and uniformed than that of perpendicular one. Also the spatial displacements of magnet array were agreed with the output signal of magnetic tunnel junction (MTJ) sensor array.

• Genomics & Informatics
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• v.4 no.1
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• pp.33-39
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• 2006

Alternative splicing (AS) is an important mechanism of producing transcriptome diversity and microarray techniques are being used increasingly to monitor the splice variants. There exist three types of microarrays interrogating AS events-junction, exon, and tiling arrays. Junction probes have the advantage of monitoring the splice site directly. Johnson et al., performed a genome-wide survey of human alternative pre-mRNA splicing with exon junction microarrays (Science 302:2141-2144, 2003), which monitored splicing at every known exon-exon junctions for more than 10,000 multi-exon human genes in 52 tissues and cell lines. Here, we describe an algorithm to deduce the relative concentration of isoforms from the junction array data. Non-negative Matrix Factorization (NMF) is applied to obtain the transcript structure inferred from the expression data. Then we choose the transcript models consistent with the ECgene model of alternative splicing which is based on mRNA and EST alignment. The probe-transcript matrix is constructed using the NMF-consistent ECgene transcripts, and the isoform abundance is deduced from the non-negative least squares (NNLS) fitting of experimental data. Our method can be easily extended to other types of microarrays with exon or junction probes.