• Title/Summary/Keyword: Negative Differential Resistance

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A Study on the Negative Differential Resistance Properties of Self-Assembly Organic Thin Film with Nitro Group (니트로기를 가진 자기조립된 유기 초박막의 부성미분저항 특성에 관한 연구)

  • Kim, Seung-Un;Son, Jung-Ho;Kim, Byoung-Sang;Shin, Hoon-Kyu;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.811-813
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    • 2003
  • We investigated the electrical properties of self-assembled (4,4'-Di(ethynylphenyl)-2'-nitro-1-thioacetylbenzene), which has been well known as a conducting molecule having possible application to molecular level negative differential resistance(NDR)[1]. Generally, the phenomenon of NDR can be characterized by the decreasing current with the increasing voltage[2]. To deposit the SAM layer onto gold electrode, we transfer the prefabricated nanopores into a 1mM self-assembly molecules in THF solution. Au(111) substrates were prepared by ion beam sputtering method of gold onto the silicon wafer. As a result, we measured the voltage-current properties and confirmed the negative differential resistance properties of self-assembled organic thin film and measured, using Scanning Tunneling Microscopy(STM).

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Development of GaAs Gunn diodes and Characterization of Negative Differential Resistance for Millimeter-wave Oscillator (밀리미터파 발진용 GaAs Gunn 다이오드 소자의 개발과 음성미분저항)

  • Yoon, Jin Seob;Nam Gung, Il Joo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.4 no.4
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    • pp.21-29
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    • 2008
  • The DC characteristics of GaAS Gunn diode are investigated as a preliminary study on the planar grade gap injector GaAs Gunn diode which is the transferred electron device with high output power and dc-rf conversion efficiency. The Gunn devices we fabricated were confirmed to have the DC characteristics of negative differential resistance(NDR). We discussed the nature of the NDR effect, including the electron intervalley transfer; the NDR effect was examined for six different cathode radii.

Negative Differential Resistance Devices with Ultra-High Peak-to-Valley Current Ratio and Its Multiple Switching Characteristics

  • Shin, Sunhae;Kang, In Man;Kim, Kyung Rok
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.6
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    • pp.546-550
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    • 2013
  • We propose a novel negative differential resistance (NDR) device with ultra-high peak-to-valley current ratio (PVCR) by combining pn junction diode with depletion mode nanowire (NW) transistor, which suppress the valley current with transistor off-leakage level. Band-to-band tunneling (BTBT) Esaki diode with degenerately doped pn junction can provide multiple switching behavior having multi-peak and valley currents. These multiple NDR characteristics can be controlled by doping concentration of tunnel diode and threshold voltage of NW transistor. By designing our NDR device, PVCR can be over $10^4$ at low operation voltage of 0.5 V in a single peak and valley current.

Microwave-Induced Negative-Differential Resistance Observed in Josephson Junction (마이크로파가 조셉슨 접합에서 유발하는 부의 미분저항)

  • Kim, Kyu-Tae;Koutovoi, Viatcheslav D.;Hong, Hyun-Kwon
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.237-237
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    • 1999
  • We have observed that a stable and reproducible Negative Differential Resistance(NDR) is induced by external microwave at low power in Nb/AlO$_x$/Al/Alo$_x$/Nb junctions. To study the erratic and pozzling NDR observations we have simulated Stewart-McCumber model in the region. Experimental results and simulation results will be presented with a discussion to draw a dynamic interpreration of the NDR.

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STM Studies of Keggin-type and Wells-Dawson-type Heteropolyacid Catalysts (Keggin 형 및 Wells-Dawson 형 헤테로폴리산 촉매의 STM 연구)

  • Park, Gyo Ik;Barteau, Mark A.;Jung, Ji Chul;Song, In Kyu
    • Korean Chemical Engineering Research
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    • v.47 no.2
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    • pp.163-168
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    • 2009
  • Negative differential resistance(NDR) behaviors of Keggin-type and Wells-Dawson-type heteropolyacids with cation, heteroatom, and polyatom substitutions were investigated by scanning tunneling microscopy. A reliable correlation between NDR peak voltage and reduction potential of heteropolyacid catalysts was established. It was found that more reducible heteropolyacid catalyst showed NDR behavior at less negative voltage, regardless of the structural difference. Thus, NDR peak voltage of heteropolyacid catalyst could be utilized as a single correlating parameter for the reduction potential of heteropolyacid catalyst.

A Study on the Forward I-V Characteristics of the Separated Shorted-Anode Lateral Insulated Gate Bipolar Transistor (분리된 단락 애노드를 이용한 수평형 SA-LIGBT 의 순방향 전류-전압 특성 연구)

  • Byeon, Dae-Seok;Chun, Jeong-Hun;Lee, Byeong-Hun;Kim, Du-Yeong;Han, Min-Ku;Choi, Yeon-Ik
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.3
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    • pp.161-166
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    • 1999
  • We investigate the device characteristics of the separated shorted-anode LIGBT (SSA-LIGBT), which suppresses effectively the negative differential resistance regime, by 2-dimensional numerical simulation. The SSA-LIGBT increases the pinch resistance by employing the highly resistive n-drift region as an electron conduction path instead of the lowly resistive n buffer region of the conventional SA-LIGBT. The negative differential resistance regime of the SSA-LIGBT is significantly suppressed as compared with that of the conventional SA-LIGBT. The SSA-LIGBT shows the lower forward voltage drop than that of the conventional SA-LIGBT.

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Fabrication of GaAs Gunn diodes and Characterization of Negative Differential Resistance (GaAs Gunn 다이오드 소자의 제작과 부성미분저항)

  • Kim, Mi-Ra;Lee, Seong-Dae;Chae, Yeon-Sik;Rhee, Jin-Koo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.7 s.361
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    • pp.1-8
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    • 2007
  • The DC characteristics of GaAs Gunn diode are investigated as a preliminary study on the planar grade gap injector GaAs Gunn diode which is the transferred electron device with high output power and dc-rf conversion efficiency. The Gunn devices we fabricated were confirmed to have the DC characteristics of negative differential resistance(NDR). We discussed the nature of the NDR effect, including the electron intervalley transfer; the NDR effect was examined for six different cathode radii.

A Study on the Negative Differential Resistance in Dipyridinium Self-Assembled Monolayers Using STM

  • Lee Nam-Suk;Shin Hoon-Kyu;Kwon Young-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • v.5C no.3
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    • pp.111-114
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    • 2005
  • Organic monolayers were fabricated onto Au(l l l) substrate by self-assembly method using dipyridinium. Also, organic single molecule in the organic monolayers was selected to measure the current-voltage (I-V) curves by using the ultrahigh vacuum scanning tunneling microscopy (UHV-STM). The organic molecule used in the experiment was dipyridinium dithioacetate, which contains thiol functional group and can be self-assembled easily onto Au(l l l) substrate. The concentration of dipyridinium dithioacetate for self-assembly procedure was I [mM/L]. To confirm the formation of self-assembled mono layers (SAMs), the differences of thickness of the self-assembled organic monolayers were observed by using an ellipsometer, and the morphology and I-V curves of the SAMs were investigated by using UHV-STM. The applied voltages were from -2 [V] to +2 [V], temperature was 300 [K]. The vacuum for measuring current of the organic single molecule was 6 $\times$ 10$^{-8}$ [Torr]. As a result, properties of the negative differential resistance (NDR) in constant voltage were found.

Non-Contact Sensing Method using PT Symmetric Circuit with Cross-Coupled NDR Circuits (크로스-결합구조의 부성 미분 저항 회로를 이용한 페리티-시간 대칭 구조의 비접촉 센서 구동 회로에 대한 연구)

  • Hong, Jong-Kyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.10-16
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    • 2021
  • This paper proposes a model that considers the parity-time symmetric structure as a state detection circuit for sensor applications using a stretchable inductor. In particular, to obtain a more practical computer simulation result, the stretchable inductor model was applied to this study model by referring to previously reported experimental results. The resistance component and phase component were controlled through the negative differential resistance circuit used in this study. In addition, the imbalance of the circuit caused by a change in the characteristics of the stretchable inductor could be compensated for using a negative differential resistance circuit. In particular, an analysis of the frequency characteristics of the sensor driving circuit of the parity-time symmetric structure proposed in this study confirmed that the Q-factor could be increased up to 20 times compared to the conventional resonant circuit.

Study on the Mophology Observation and Electrical Properties of Dipyridinium Organic Monolayer Using STM (STM을 이용한 Dipyridinium 유기 단분자막의 모폴로지 관찰 및 전기적 특성 연구)

  • Lee Nam-Suk;Shin Hoon-Kyu;Kwon Young-Soo
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.54 no.2
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    • pp.51-54
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    • 2005
  • In this work, the attempt has been made to investigate the morphology of self-assembled dipyridinium dithioacetate on Au(111) substrate by Scanning Tunneling Microscopy(STM). Also, we measured electrical properties(I-V) using Scanning Tunneling Spectroscopy(STS). Sample used in this experiment is dipyridinium dithioacetate, which contains thiol functional group, this structure that can be self-assembled easily to Au(111) substrate. The self-assembly procedure was used for two different concentrations, 0.5 mM/ml and 1 mM/ml. Dilute density of sample by 0.5 mM/ml, 1 mM/ml and observed dipyridinium dithioacetate's image by STM after self-assembled on Au(111) substrate. The structure of STM tip-SAMs-Au(111) substrate has been used measurement for electrical properties(I-V) using STS. The current-voltage(I-V) measurement result, observed negative differential resistance(NDR) properties.