• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.682-684
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• 2003

In this paper, we have designed the p-type SiGe MOSFET and analyzed the electrical characteristics over the temperature range of 300K and 77K. When the gate voltage is biased to -1.5V, the threshold voltage values are -0.97V and -1.15V at room temperature and 77K, respectively. We know that the operating characteristics of SiGe MOSFET is superior to the basic Si MOSFET which the threshold voltage is -1.36V.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.3
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• pp.474-477
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• 2003

In this paper, we have designed the p-type SiGe MOSFET and analyzed the electrical characteristics over the temperature range or 300K and 77K. When the gate voltage is biased to -1.5V, the threshold voltage values are -0.97V and -1.15V at room temperature and 77K, respectively. We know that the operating characteristics of SiGe MOSFET is superior to the basic Si MOSFET which the threshold voltage is -1.36V.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.910-917
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• 2009

We have designed a new structures of Junction Field Effect Transistor(JFET) using SILVACO simulation to improve electrical properties and process reliability. The device structure and process conditions of Si control JFET(Si JFET) were determined to set cut off voltage and drain current(at Vg=0 V) to -0.46 V and $300\;{\mu}A$, respectively. Among many design parameters influencing the performance of the device, the drive-in time of p-type gate is presented most predominant effects. Therefore we newly designed SiGe JFET, in which SiGe layers were placed above and underneath of Si-channel. The presence of SiGe layer could lessen Boron into the n-type Si channel, so that it would be able to enhance the structural consistency of p-n-p junction. The influence of SiGe layer could be explained in conjunction with boron diffusion and corresponding I-V characteristics in comparison with Si-control JFET.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.847-853
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• 2016

Applications of Si have been increasingly exploited and extended to More-Moore, More-than-Moore, and beyond-CMOS approaches. Ge is regarded as one of the supplements for Si owing to its higher carrier mobilities and peculiar band structure, facilitating both advanced and optical applications. As an emerging metal-oxide device, the junctionless field-effect transistor (JLFET) has drawn considerable attention because of its simple process, less performance fluctuation, and stronger immunity against short-channel effects due to the absence of anisotype junctions. In this study, we investigated lateral field scalability, which is equivalent to channel-length scaling, in Si and Ge JLFETs. Through this, we can determine the usability of Si CMOS and hypothesize its replacement by Ge. For simulations with high accuracy, we performed rigorous modeling for ${\mu}_n$ and ${\mu}_p$ of Ge, which has seldom been reported. Although Ge has much higher ${\mu}_n$ and ${\mu}_p$ than Si, its saturation velocity ($v_{sat}$) is a more determining factor for maximum $I_{on}$. Thus, there is still room for pushing More-Moore technology because Si and Ge have a slight difference in $v_{sat}$. We compared both p- and n-type JLFETs in terms of $I_{on}$, $I_{off}$, $I_{on}/I_{off}$, and swing with the same channel doping and channel length/thickness. $I_{on}/I_{off}$ is inherently low for Ge but is invariant with $V_{DS}$. It is estimated that More-Moore approach can be further driven if Si is mounted on a JLFET until Ge has a strong possibility to replace Si for both p- and n-type devices for ultra-low-power applications.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.356-356
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• 2013

Monolithic 3D-IC는 현대 집적회로에서 interconnect로 인해 발생되는 여러 문제들을 해결하기 위해 새롭게 제시되고 있는 기술적 개념으로 구현 시 하위 소자 및 interconnet들에 영향을 주지 않는 저온공정이 필수적이다. 특히 germanium (Ge)은 낮은 녹는점 및 높은 캐리어 이동도 덕분에 3D-IC 구현 시 상위 소자의 channel 물질에 적합한 것으로 알려져 있다. 최근 이러한 Ge을 결정화하기 위해 solid phase crystallization (SPC), metal induced crystallization (MIC), laser annealing과 같은 결정화 방법들이 보고되고 있다. 현재까지 SPC 방법에 의해 얻어진 poly-Ge의 도핑농도 및 이동도와 같은 전기적 특성에 대한 분석은 수행된 바 있으나 3D-IC 공정에 적용이 가능한 MIC 기술을 통해 얻어진 poly Ge 필름에 대한 전기적 특성분석은 부족한 상황이다. 본 연구는 SPC 뿐만 아니라 MIC 방법을 통해 ${\alpha}$-Ge를 결정화시키고 얻어진 poly-Ge 필름의 전기적 특성을 XRD 및 hall effect measurement를 통해 분석하였다. 특히 일반적으로 Ge 내에서 p-type dopant로 동작을 하는 defect과 n-type dopant인 phosphorus 관계를 고려하여 여러 온도에서 SPC 및 MIC에 의해 얻어진 phosphorus doped poly-Ge 필름들의 전기적 특성을 분석하였다.

• Journal of the Korean Magnetics Society
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• v.19 no.4
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• pp.133-137
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• 2009

$MnGeP_2$ thin films grown on GaAs exhibit room-temperature ferromagnetism with $T_C{\sim}$320 K, based on both magnetization and resistance measurements. The coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. The anomalous Hall effect was observed, indicating spin polarization of the carriers. Hysteresis has been observed in both magnetoresistance and Hall measurements. The current-voltage characteristics of a $MnGeP_2$ film grown on an n-type GaAs substrate display semiconducting behavior.

• Journal of Powder Materials
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• v.14 no.4
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• pp.272-276
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• 2007

P-type thermoelectric material $Si_{0.8}Ge_{0.2}$ was sintered by Hot Press process (HP) and the effect of boron ($0.25{\sim}2$ at%) addition on the thermoelectric properties were reported. To enhance the thermoelectric performances, the $Si_{0.8}Ge_{0.2}$, alloys were fabricated by mechanical alloying (MA) and HP. The carrier of p-type SiGe alloy was controlled by B-doping. The effect of sintering condition and thermoelectric properties were investigated. B-doped SiGe alloys exhibited positive seebeck coefficient. The electrical conductivity and thermal conductivity were increased at the small amount of boron content ($0.25{\sim}0.5$ at%). However, they were decreased over 0.5 at% boron content. As a result, the small addition of boron improved the Z value. The Z value of 0.5 at% B doped $Si_{0.8}Ge_{0.2}$ B alloy was $0.9{\times}10{-4}/K$, the highest value among the prepared alloys.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.773-776
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• 2003

In this paper, we have designed the p-type SiGe MOSFET and analyzed the electrical characteristics. When the gate voltage is biased to -1.5V, the threshold voltage values are -0.97V and -1.15V at room temperature and 77K, respectively. We know that the operating characteristics of SiGe MOSFET is superior to the basic Si MOSFET which the threshold voltage is -1.36V.

• ETRI Journal
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• v.25 no.4
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• pp.247-252
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• 2003

This paper presents results from experiments on laser-annealed SiGe-selective epitaxial growth (LA-SiGe-SEG). The SiGe-SEG technology is attractive for devices that require a low band gap and high mobility. However, it is difficult to make such devices because the SiGe and the highly doped region in the SiGe layer limit the thermal budget. This results in leakage and transient enhanced diffusion. To solve these problems, we grew in situ doped SiGe SEG film and annealed it on an XMR5121 high power XeCl excimer laser system. We successfully demonstrated this LA-SiGe-SEG technique with highly doped Ge and an ultra shallow junction on p-type Si (100). Analyzing the doping profiles of phosphorus, Ge compositions, surface morphology, and electric characteristics, we confirmed that the LA-SiGe-SEG technology is suitable for fabricating high-speed, low-power devices.

• Nuclear Engineering and Technology
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• v.7 no.2
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• pp.85-94
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• 1975

The n-type germanium crystals have been irradiated by $^{60}$ Co gamma-ray with 647 Mrad at room temperature for compensation. The Ge(${\gamma}$) detectors were fabricated from the gamma-ray irradiated germanium single crystals. The detector characteristics of the Ge (${\gamma}$) detectors were comparable to those of thin Ge(Li) detectors and high purity germanium detectors. The thermal stability of the Ge (${\gamma}$) detector showed a feasibility for ambient temperature storage.