• Title/Summary/Keyword: 쇼트키 방출

Search Result 7, Processing Time 0.021 seconds

Thermo-Field emission in silicon nanomembrane ion detector for mass spectrometry (실리콘 나노 박막의 열-전계 방출효과를 이용한 분자 질량분석)

  • Park, Jong-Hoo
    • Journal of the Korean Applied Science and Technology
    • /
    • v.30 no.4
    • /
    • pp.586-591
    • /
    • 2013
  • This paper describes the characteristics of thermo-field emission in a freestanding silicon nanomembrane under ion bombardment with various thermal and field conditions. The thermal effect and field effect in thermo-field emission in silicon nanomembrane are investigated by varying kinetic energy of ions and electric field applied to the silicon nanomembrane surface, respectively. We found that thermo-field emission increases linearly as the electric field increases, when the electric field intensity is lower than the threshold. The thermo-field emission (schottky effect) increases proportionally to the power of temperature, which agree well with the predictions of a thermo-field emission model.

The Properties of Electrical Conduction and Photoconduction in Polyphenylene Sulfide(PPS) by Uniaxial Elongation (일축연신에 따른 Polyphenylene sulfide(PPS)의 전기전도 및 광전도 특성)

  • 이운용;장동욱;강성화;임기조;류부형
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1998.06a
    • /
    • pp.223-226
    • /
    • 1998
  • In this paper, we have investigated how morphology and electrical properties in Polyphenylene sulfide(PPS) are changed by uniaxial elongation. XRD pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. Electrical conduction mechanism of PPS is explained as schottky emission from analysis of electrical current. The electrical current is decreased by increasing elongation ratio. The conductivity is changed remarkably above the glass transition temperature around $(82^{\circ}C)$. The band gap of PPS is evaluated as 3.9-4(eV) from the results of photoconductivity. Increarnent of elongation ratio gives us some information about deep trap formation from photocurrent.

  • PDF

The Properties of Electrical Conduction and Photoconduction in polyphenylene Sulfide(PPS) by Uniaxal Elongation (일축연신에 따른 Polyphenylene Sulfide(PPS)의 전기전도 및 광전도 특성)

  • Lee, Un-Yong;Jang, Dong-Uk;Shin, Tae-Su;Lim, kee-Joe;Ryu, Boo-Hyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.10
    • /
    • pp.763-767
    • /
    • 1998
  • In this paper, it is investigated how the morphology and electrical properties in Polyphenylene Sulfide(PPS) changed by uniaxial elongation. XRD(X-ray diffraction) pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. electrical conduction mechanism of PPS is explained as Schottky emission mechanism. the electrical current is decreased by increasing elongation ratio. The conductivity is changed considerably above the glass transition temperature around 82(>$^{\circ}C$). The band gap of PPS is evaluated as 3.7~4(eV)

  • PDF

Electrical properties of sputtered vanadium oxide thin films in Al/$VO_x$/Al device structure (Al/$VO_x$/Al 소자 구조에서 스퍼터된 바나듐 산화막의 전기적 특성)

  • 박재홍;최용남;최복길;최창규;김성진
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.07a
    • /
    • pp.460-463
    • /
    • 2000
  • The current-voltage characteristics of the sandwich system at different annealing temperatures and different bias voltages have been studied. In order to prepare the Al/V$O_X$/Al sandwich devices structure, thin films of vanadium oxide(V$O_X$) was deposited by r.f. magnetron sputtering from $V_2$$O_5$ target in 10% gas mixture of argon and oxygen, and annealed during lhour at different temperatures in vacuum. Crystall structure, surface morphology, and thickness of films were characterized through XRD, SEM and I-V characteristics were measured by electrometer. The films prepared below 20$0^{\circ}C$ were amorphous, and those prepared above 300 $^{\circ}C$were polycrystalline. At low fields electron injected to conduction band of vanadium oxide and formed space charge, current was limited by trap. Conduction mechanism at mid fields due to Schottky emission, while at high fields it changed to Fowler-Nordheim tunneling effects.

  • PDF

The microstructure and conduction mechanism of the nonlinear ZnO varistor with $Al_2O_3$ additions ($Al_2O_3$가 미량 첨가된 비선형성 ZnO 바리스터의 미세구조와 전도기구)

  • 한세원;강형부;김형식
    • Electrical & Electronic Materials
    • /
    • v.9 no.7
    • /
    • pp.708-718
    • /
    • 1996
  • The microstructure and electrical properties of the nonlinear ZnO varistor with A1$_{2}$ $O_{3}$ additions is investigated. The variation of nonlinear behavior with A1$_{2}$ $O_{3}$ additions is indicated from J-E and C-V measurement to be a result of the change of the interface defects density $N_{t}$ at the grain boundaries and the donor concentration $N_{d}$ in the ZnO grains. The optimum composition which has the nonlinear coefficients of -57 was observed in the sample with 0.005wt% A1$_{2}$ $O_{3}$ additions. The conduction mechanism at the pre-breakdown region is consistent with a Schottky thermal emission process obeying a relation given by $J^{\var}$exp[-(.psi.-.betha. $E^{1}$2/)kT] and the conduction process at the breakdown region follows a Fowler-Nordheim tunneling mechanism of the form $J^{\var}$exp(-.gamma./E).

  • PDF

Cold Cathode using Avalanche Phenomenon at the Inversion Layer (반전층에서의 애벌런치 현상을 이용한 냉음극)

  • Lee, Jung-Yong
    • Journal of the Korean Vacuum Society
    • /
    • v.16 no.6
    • /
    • pp.414-423
    • /
    • 2007
  • Field Emission Display(FED) has significant advantages over existing display technologies, particularly in the area of small and high quality display. In order to test the feasibility of fabricating the System-on-Chip(SOC) with FED, we conducted the experiment to use the p-n junction as an electron beam source for the flat panel display. A novel structure was constructed to form p-n junctions by generating inversion layer with the electric field from the cantilever style gate. When we applied more than 220V at the cantilever style gate which has a height of $1{\mu}m$, avalanche breakdown onset was successfully achieved. The characteristics was compared with the electron emission from the ultra shallow junction in the avalanche region. The experiment result and the future direction were discussed.

Characterization of the Schottky Barrier Height of the Pt/HfO2/p-type Si MIS Capacitor by Internal Photoemission Spectroscopy (내부 광전자방출 분광법을 이용한 Pt/HfO2/p-Si Metal-Insulator-Semiconductor 커패시터의 쇼트키 배리어 분석)

  • Lee, Sang Yeon;Seo, Hyungtak
    • Korean Journal of Materials Research
    • /
    • v.27 no.1
    • /
    • pp.48-52
    • /
    • 2017
  • In this study, we used I-V spectroscopy, photoconductivity (PC) yield and internal photoemission (IPE) yield using IPE spectroscopy to characterize the Schottky barrier heights (SBH) at insulator-semiconductor interfaces of Pt/$HfO_2$/p-type Si metal-insulator-semiconductor (MIS) capacitors. The leakage current characteristics of the MIS capacitor were analyzed according to the J-V and C-V curves. The leakage current behavior of the capacitors, which depends on the applied electric field, can be described using the Poole-Frenkel (P-F) emission, trap assisted tunneling (TAT), and direct tunneling (DT) models. The leakage current transport mechanism is controlled by the trap level energy depth of $HfO_2$. In order to further study the SBH and the electronic tunneling mechanism, the internal photoemission (IPE) yield was measured and analyzed. We obtained the SBH values of the Pt/$HfO_2$/p-type Si for use in Fowler plots in the square and cubic root IPE yield spectra curves. At the Pt/$HfO_2$/p-type Si interface, the SBH difference, which depends on the electrical potential, is related to (1) the work function (WF) difference and between the Pt and p-type Si and (2) the sub-gap defect state features (density and energy) in the given dielectric.