• 제목/요약/키워드: device physics

검색결과 719건 처리시간 0.027초

In-situ rf treatment of multiwall carbon nanotube with various post techniques for enhanced field emission

  • Ahn, Kyoung-Soo;Kim, Jun-Sik;Kim, Ji-Hoon;Kim, Chae-Ok;Hong, Jin-Pyo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.859-862
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    • 2003
  • Well-aligned multiwall carbon nanotubes (MWCNTs) were prepared at low temperature of 400 $^{\circ}C$ by utilizing a radio frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system. The MWCNTs were treated by an external rf plasma source and an ultra-violet laser in order to modify structural defect of carbon nanotube and to ablate possible contamination on carbon nanotube surface. Structural properties of carbon nanotubes were investigated by using a scanning electron microscopy (SEM), Raman spectroscopy, Fourier transformer Infrared spectroscopy (FTIR) and transmission electron microscope (TEM). In addition, the emission properties of the MWNTs were measured for the application of field emission display (FED) in near future. Various post treatments were found to improve the field emission property of carbon nanotubes.

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그래핀 산화물 소자에서의 산소 작용기 이동 연구 (Investigation of Oxygen Functional Group Movement in Graphene Oxide Devices)

  • 기은희;;전지훈;최진식;박배호
    • 센서학회지
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    • 제32권2호
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    • pp.100-104
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    • 2023
  • In this study, a device was fabricated to check the possibility of a memory device by controlling the oxygen functional groups in graphene oxide formed with a 45-second exposure time. We discovered that graphene oxide can be formed using the ultraviolet (UV) light treatment method with different exposure times. Moreover, Raman spectroscopy measurement revealed that the oxygen functional groups can be moved by controlling the voltage. We further studied the change in the local graphene oxide region, which was found to be related to the modulation of the electrical properties of the device. Therefore, the fabricated graphene oxide device can be used as a wettability switching membrane and graphene-based ion transport device.

Effect of the LiF anode interfacial layer on polymer light emitting diodes

  • Sohn, Sun-Young;Lee, Dae-Woo;Park, Keun-Hee;Jung, Dong-Geun;Kim, H.M.;Manna, U.;Yi, J.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1056-1058
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    • 2005
  • Electrical and optical characteristics of MEH-PPV-based PLEDs with the LiF anode interfacial layer were investigated. The maximum luminance efficiency of the device with a LiF anode interfacial layer of 1-nm-thick was 3.0 lm/W, which is higher than 1.97 lm/W of the device without a LiF layer. By inserting LiF, excess injected holes from ITO anode can be blocked and hence the recombination ratio of electrons and holes can be increased in the emitting layer to improve device efficiency.

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Hydrazine Doped Graphene and Its Stability

  • Song, MinHo;Shin, Somyeong;Kim, Taekwang;Du, Hyewon;Koo, Hyungjun;Kim, Nayoung;Lee, Eunkyu;Cho, Seungmin;Seo, Sunae
    • Applied Science and Convergence Technology
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    • 제23권4호
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    • pp.192-199
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    • 2014
  • The electronic property of graphene was investigated by hydrazine treatment. Hydrazine ($N_2H_4$) highly increases electron concentrations and up-shifts Fermi level of graphene based on significant shift of Dirac point to the negative gate voltage. We have observed contact resistance and channel length dependent mobility of graphene in the back-gated device after hydrazine monohydrate treatment and continuously monitored electrical characteristics under Nitrogen or air exposure. The contact resistance increases with hydrazine-treated and subsequent Nitrogen-exposed devices and reduces down in successive Air-exposed device to the similar level of pristine one. The channel conductance curve as a function of gate voltage in hole conduction regime keeps analogous value and shape even after Nitrogen/Air exposure specially whereas, in electron conduction regime change rate of conductance along with the level of conductance with gate voltage are decreased. Hydrazine could be utilized as the highly effective donor without degradation of mobility but the stability issue to be solved for future application.

Characteristics of a Carbon Nanotube-based Tunnel Magnetoresistance Device

  • Kim, Jinhee;Woo, Byung-Chill;Kim, Jae-Ryoung;Park, Jong-Wan;So, Hye-Mi;Kim, Ju-Jin
    • Journal of Magnetics
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    • 제7권3호
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    • pp.98-100
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    • 2002
  • Tunnel magnetoresistive devices using an individual multi-walled carbon nanotube were fabricated and their low-temperature electrical transport propertiers were investigated. With the ferromagnetic Co electrodes, the multi-walled carbon nanotube exhibited hysteretic magnetoresistance curve at low temperatures. Depending on the temperature and the bias current, the magnetoresistance ratio can be as high as 16% at the temperature of 2.2 K. Such high magnetoresistance ratio indicates a long diffusion length of the multi-walled carbon nanotube.