• 한국전기전자재료학회논문지
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• 제27권5호
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• pp.276-281
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• 2014

A high-responsive Schottky device has been achieved by forming a thin metal deposition on a Si substrate. Two-different metals of Ni and Ag were used as a Schottky metal contact with a thickness about 10 nm. The barrier height formation between metal and Si determines the rectifying current profiles. Ag-embedding Schottky device gave an extremely high response of 17,881 at a wavelength of 900 nm. An efficient design of Schottky device may applied for photoelectric devices, including photodetectors and solar cells.

• 센서학회지
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• 제18권3호
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• pp.222-225
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• 2009

This paper describes the fabrication and characteristics of Schottky micro hydrogen sensors for high temperatures by using polycrystalline(poly) 3C-SiC thin films grown on Si substrates with thermal oxide layer using APCVD. Pd/poly 3C-SiC Schottky diodes were made and evaluated by I-V and C-V measurements. Electric current density and barrier height voltage were $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices could operate stably at about 400 $^{\circ}$. The characteristics of implemented sensors have been investigated in terms of sensitivity, linearity of response, response rate, and response time. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature $H_2$ sensor applications.

• 센서학회지
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• 제17권6호
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• pp.414-417
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• 2008

This paper describes the fabrication of a Pd/poly 3C-SiC Schottky diode and its characteristics, in which the poly 3C-SiC layer and Pd Schottky contact were deposited by using APCVD and sputter, respectively. Crystalline quality, uniformity, and preferred orientations of the Pd thin film were evaluated by SEM and XRD, respectively. Pd/poly 3C-SiC schottky diodes were fabricated and characterized by I-V and C-V measurements. Its electric current density Js and barrier height voltage were measured as $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices were operated until about $400^{\circ}C$. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature chemical sensor applications.

• 한국진공학회지
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• 제9권3호
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• pp.242-248
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• 2000

고주파 스퍼터링 방법으로 증착조건을 변화시키면서 BST 박막을 제작하였다. 증착온도가 높을수록, Ar/O$_2$비가 적을수록 우수한 전기적 특성을 보였다. 누설전류 전도기구를 분석하기 위해 Schottky모델과 modified-Schottky모델을 도입하였다. BST 박막의 누설전류 전도기구는 기존의 Schottky모델이 아니라 modified-Schottky 모델을 따른다는 것을 알았다. Modified-Schottky 모델을 사용하여 광학유전상수 $\varepsilon$=4.9, 이동도 $\mu$=0.019 $\textrm{cm}^2$/V-s, 그리고 장벽높이 $\phi_b$ =0.79 eV를 구하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.133-133
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• 2008

Recently, as the down-scailing of field-effect transistor devices continues, Schottky-barrier field-effect transistors (SB-FETs) have attracted much attention as an alternative to conventional MOSFETs. SB-FETs have advantages over conventional devices, such as low parasitic source/drain resistance due to their metallic characteristics, low temperature processing for source/drain formation and physical scalability to the sub-10nm regime. The good scalability of SB-FETs is due to their metallic characteristics of source/drain, which leads to the low resistance and the atomically abrupt junctions at metal (silicide)-silicon interface. Nevertheless, some reports show that SB-FETs suffer from short channel effect (SCE) that would cause severe problems in the sub 20nm regime.[Ouyang et al. IEEE Trans. Electron Devices 53, 8, 1732 (2007)] Because source/drain barriers induce a depletion region, it is possible that the barriers are overlapped in short channel SB-FETs. In order to analyze the SCE of SB-FETs, we carried out systematic studies on the Schottky barrier overlapping in short channel SB-FETs using a SILVACO ATLAS numerical simulator. We have investigated the variation of surface channel band profiles depending on the doping, barrier height and the effective channel length using 2D simulation. Because the source/drain depletion regions start to be overlapped each other in the condition of the $L_{ch}$~80nm with $N_D{\sim}1\times10^{18}cm^{-3}$ and $\phi_{Bn}$ $\approx$ 0.6eV, the band profile varies as the decrease of effective channel length $L_{ch}$. With the $L_{ch}$~80nm as a starting point, the built-in potential of source/drain schottky contacts gradually decreases as the decrease of $L_{ch}$, then the conduction and valence band edges are consequently flattened at $L_{ch}$~5nm. These results may allow us to understand the performance related interdependent parameters in nanoscale SB-FETs such as channel length, the barrier height and channel doping.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 광주전남지부
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• pp.87-90
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• 2006

Two SiC radiation detector samples were irradiated by Co-60 gamma rays. The irradiation was performed with dose rates of 5 kGy/hour and 15 kGy/hour for 8 hours, respectively. Metal/semiconductor contacts on the surface were fabricated by using a thermal evaporator in a high vacuum condition. The SiC detectors have metal contacts of Au(2000 ${\AA}$)/Ni(300 ${\AA}$) at Si-face and of Au(2000 ${\AA}$)/Ti(300 ${\AA}$) at C-face. I-V characteristics of the SiC semiconductor were measured by using the Keithley 4200-SCS parameter analyzer with voltage sources included. From the I-V curve, we analyzed the Schottky barrier heights(SBHs) on the basis of the thermionic emission theory. As a result, the 6H-SiC semiconductor showed- similar Schottky barrier heights independent to the dose rates of the irradiation with Co-60 gamma rays.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2004년도 제27회 학술발표회 초록집
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• pp.165-165
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• 2004

• 새물리
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• 제68권12호
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• pp.1288-1292
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• 2018

반도체 특성을 가지는 이차원 전이금속 칼코겐 화합물 $MoS_2$와 강자성이면서 금속성을 가지는 $VS_2$로 이루어진 수평접합 구조를 기반으로 해서, 0%부터 10%까지 2% 간격으로 변형에 따른 쇼트키 장벽(Schottky Barrier) 변화를 밀도 범함수 이론 계산을 통해 연구하였다. 그 결과, 홀의 쇼트키 장벽이 전자의 쇼트키 장벽에 비해 훨씬 작고, 홀의 쇼트키 장벽 높이가 변형에 따라 선형적으로 감소함을 발견하였다. 특히, 8% 이후의 변형에서 홀의 스핀 업 쇼트키 장벽의 높이가 0에 가까워지는 임계 변형값이 존재함을 발견하였고, 이 임계 변형값 이상에서는 스핀 업 성분의 홀이 $MoS_2/VS_2$ 수평접합구조를 통해 쇼트키 장벽 없이 쉽게 흐르게 됨을 알게 되었다. 이러한 연구 결과는 향후, 변형을 통한 이차원 전이금속 칼코겐 수평 접합구조 기반 소자 특성 최적화에 중요한 기초자료로 이용될 것으로 기대한다.

• 전자공학회논문지A
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• 제31A권12호
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• pp.56-63
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• 1994

The effects of sulfur treatments on the barrier heithts of Schottky contacts and the interface-state density of metal-insulator-semiconductor (MIS) capacitors on InP have been investigated. Schottky contacts were formed by the evaporation of Al, Au, and Pt on n-InP substrate before and after (NH$_{4}$)$_{2}$S$_{x}$ treatments, respectively. The barrier height of InP Schottky contacts was measured by their current-voltage (I-V) and capacitance-voltage (C_V) characteristics. We observed that the barrier heights of Schottky contacks on bare InP were 0.35~0.45 eV nearly independent of the metal work function, which is known to be due to the surface Fermi level pinning. In the case of sulfur-treated Au/InP ar Pt/InP Schottky diodes, However, the barrier heights were not only increased above 0.7 eV but also highly dependent on the metal work function. We have also investigated effects of (NH$_{4}$)$_{2}$S$_{x}$ treatments on the distribution of interface states in Si$_{3}$N$_{4}$InP MIS diodes where Si$_{3}$N$_{4}$ was provided by plasma enhanced chemical vapor deposition (PECVD). The typical value of interface-state density extracted feom 1 MHz C-V curve of sulfur-treated SiN$_{x}$/InP MIS diodes was found to be the order of 5${\times}10^{10}cm^{2}eV^{1}$. This value is much lower than that of MiS diodes made on bare InP surface. It is certain, therefore, that the (NH$_{4}$)$_{2}$S$_{x}$ treatment is a very powerful tool to enhance the barrier heights of Au/n-InP and Pt/n-InP Schottky contacts and to reduce the density of interface states in SiN$_{x}$/InP MIS diode.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.938-940
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• 1999

We have fabricated SiC Schottky diode for high temperature applications. SiC thin film for drift region has been deposited by ICP-CVD. In order to establish metallization conditions, we have extracted the device parameters of the Schottky diode from the forward I-V characteristics and the C-V characteristics as a function of temperature. The ideality factor was varied from 2.07 to 1.15 and the barrier height was also varied from 1.26eV to 1.92eV with increase of temperature. The reverse blocking voltage was 183 V.