• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.368.1-368.1
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• 2014

We proposed amorphous GeSe-based ReRAM device of metal-insulator-metal (M-I-M) structure. The operation characteristics of memory device occured unipolar switching characteristics. By introducing the concepts of valance-alternation-pairs (VAPs) and chalcogen vacancies, the unipolar resistive switching operation had been explained. In addition, the current transport behavior were analyzed with space charge effect of VAPs, Schottky emission in metal/GeSe interface and P-F emission by GeSe bulk trap in mind. The GeSe ReRAM device of M-I-M structure indicated the stable memory switching characteristics. Furthermore, excellent stability, endurance and retention characteristics were also verified.

• 진공이야기
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• 제5권2호
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• pp.18-22
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• 2018

wo dimensional (2D) van der Waals (vdW) nanosheet semiconductors have recently attracted much attention from researchers because of their potentials as active device materials toward future nano-electronics and -optoelectronics. This review mainly focuses on the features and applications of state-of-the-art vdW 2D material devices which use transition metal dichalcogenides, graphene, hexagonal boron nitride (h-BN), and black phosphorous: field effect transistors (FETs), complementary metal oxide semiconductor (CMOS) inverters, Schottky diode, and PN diode. In a closing remark, important remaining issues of 2D vdW devices are also introduced as requests for future electronics and photonics applications.

• 한국진공학회지
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• 제9권4호
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• pp.379-381
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• 2000

Organic materials have potential advantages to be utilized as semiconductors in field effect transistors and light emmiting diodes. Gold, Aluminium, Silver, Chromium and Indium are used by electrodes. Gold is ohmic contact and the others are schottky contact. In this study, Pentacene and various electrode materials were deposited by Organic Molecular Beam Deposition (OMBD) and vacuum evaporation respectively. Those films were photolithographically patterned for measurements. These devices showed no degration after a 15 days of storage in laboratory environment.

• Journal of Electrical Engineering and information Science
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• 제2권3호
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• pp.95-98
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• 1997

A nonlinear optical-microwave interaction is carried out in an uniplanar CPW-to-Slotline ring resonator on the semi-insulating GaAs substrate, in which a Schottky photodetector is monolithically integrated as a coupling gap. When the capacitive reactance of the detetor is modulated, the parametric amplification effect of the mixer occurs. In this device structure, the parametric amplification gain of 20 dB without the applied bias in RF signal is obtained. This microwave optoelectronic mixer can be used in the fiber-optic communication link.

• 전자공학회지
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• 제13권1호
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• pp.86-95
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• 1986

The basic physical principles involved in the operation of monolithic magnetic sensors are reviewed and technological aspects outlined. More or less conventional devices based on Hall effect, magnetoresistance or current path deflection are described. It is shown that such sensors with 2, 3, 4 or 5 terminal contacts are achievable with standard silicon integrated circuit process. Several kinds of magnetodiodes (p+nn+,p+n, Schottky, MOS, memory, CMOS) have been fabricated on Si and on SOS films and present attractive properties. Finally, the magneto-transistor family is discussed with emphasis to split-terminals, CMOS, unijunction and fila-mentary devices.

• Transactions on Electrical and Electronic Materials
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• 제10권4호
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• pp.107-110
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• 2009

In this study, the Hall effect has been studied in n-GaAs samples characterized by V/IIl growth ratios of 25, 50 and 100 and prepared by metal organic chemical vapor deposition. For the Hall effect measurements, the grown samples were cut to a size of 1${\times}$1 cm. The measurements were carried out at room temperature, using Indium contact metal at the four corners of the samples. According to the experimental results, the Schottky effect was not ovservation. Also for the n-GaAs sample of V/Ill 100 ratio the electron drift velocity was very high.

• 한국산학기술학회논문지
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• 제20권7호
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• pp.16-19
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• 2019

박막이 얇아질수록 전기적인 특성이 좋아지려면 비정질구조가 유리하다. 비정질구조는 케리어가 공핍되는 특징을 이용하여 전도성을 높이는데 효과가 있을 수 있다. 이러한 특성을 확인하는 방법으로 전위장벽이 형성되는 쇼키접합에 대한 연구가 필요하다. 비정질구조와 쇼키접합에 대하여 조사하기 위하여 $SiO_2/SnO_2$ 박막을 준비하였으며, $SiO_2$ 박막은 Ar=20 sccm 만들고 $SnO_2$ 박막은 아르곤과 산소의 유량을 각각 20 sccm으로 혼합가스를 사용하였으며, 마그네트론 스퍼터링 방법으로 $SnO_2$의을 증착하고 $100^{\circ}C$와 $150^{\circ}C$에서 열처리를 하였다. 비정질구조가 만들어지는 조건을 알아보기 위하여 XRD 패턴을 조사하고 C-V, I-V 측정을 실시하여 Al 전극을 만들고 전기적인 분석을 실시하였다. 공핍층은 열처리과정을 통하여 전자와 홀의 재결합으로 형성되는데 $SiO_2/SnO_2$ 박막은 $100^{\circ}C$에서 열처리를 한 경우 공핍층이 잘 형성이 되었으며, 미시영역에서는 전기적으로 전류가 크게 작용하는 것을 확인하였다. $100^{\circ}C$에서 열처리를 한 비정질의 $SiO_2/SnO_2$ 박막은 XRD 패턴에서 $33^{\circ}$에서는 픽이 나타나지 않았으며, $44^{\circ}$에서는 픽이 생겼다. 쇼키접합에 의해서 거시적(-30V<전압<30V)으로는 절연체 특성이 보였으나 미시적(-5V<전압<5V)으로는 전도성이 나타났다. 케리어가 부족한 공핍층에서의 전도는 확산전류에 의하여 전도가 이루어진다. 미소영역에서 동작하는 소자인 경우에는 공핍효과에 의한 쇼키접합이 전류의 발생과 전도에 유리하다는 것을 확인하였다.

• 한국세라믹학회지
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• 제34권8호
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• pp.803-810
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• 1997

Ba0.5Sr0.5TiO3박막을 RF 마그네트론 스퍼터링법을 이용하여 Pt/Ti/SiO2/Si(100) 기판에 증착하였다 .누설전류에 영향을 주는 것으로 알려진 열처리 조건, dopant 효과 등을 평가하고자 이온반경이Ti와 유사하고 대부분이 Ti 자리를 치환하는 것으로 알려진 Nb와 Al을 각각 danor와 acceptor로 선택하여 BST 박막에 첨가한 후 누설전류를 측정하였다. 고온에서 in-situ 증착된 BST 박막은 거친 표면 형상을 보이며 낮은 전압에서 파괴가 발생하고, Nb 첨가로 누설전류가 증가하였다. 삼온 증착후 후열처리된 박막은 표면 형상도 평할도가 증가하였으며 in-situ로 제조된 박막에 비해 높은 파괴전압과 낮은 누설전류를 나타내었다. 특히 Al이 첨가된 BST 박막의 누설전류밀도는 ~10A/cm2로 도핑을 하지 않은 박막이나 Nb가 첨가된 박막에 비해 매우 낮은 누설전류밀도를 나타내었으며, 이는 산화로 인한 산소공공의 감소, 이동 가능한 hole의 감소와 후열처리과정중 계면 및 입계의 산화로 Schottky 장벽에 높아진 결과로 판단된다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권2호
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• pp.215-220
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• 2016

Monolithically integrated devices are strongly desired in next generation power ICs to reduce the chip size and improve the efficiency and frequency response. Three examples of the embedment of different functional diode(s) into AlGaN/GaN heterojunction field-effect transistors are presented, which can minimize the parasitic effects caused by interconnection between devices.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권1호
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• pp.104-109
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• 2008

A simple and efficient way of modeling backgating in GaAs MESFET's is presented through depletion width modulation of Schottky junction and channel-substrate interface. It is shown semi-empirically that such a modulation of depletion widths causes serious troubles in designing precision circuits since backgating drastically reduces threshold voltage of MESFET as well as drain current. Finally, some of the results are compared with reported experimental results. This model may serve as a starting point for rigorous characterization of backgating effect on various device parameters of GaAs MESFET's.