• 제목/요약/키워드: Atomic force microscopy (AFM)

검색결과 782건 처리시간 0.038초

Si Nanostructure on Graphene

  • Han, Yong;Kim, Heeseob;Hwang, Chan-Cuk;Lee, Hangil;Kim, Bongsoo;Kim, Ki-jeong
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.184.1-184.1
    • /
    • 2014
  • Nanostructures on Graphene surface receive highly attraction for many applications ranging from sensing technologies to molecular electronics. Recently J. Jasuja et al. reported the electrical property tailoring and Raman enhancement by the implantation and growth of dendritic gold nanostructures on graphene derivatives [ACSNANO, 3, 2358, 2013] Here, we introduced Si vapor on the graphen to induce the nanostructure. The surface property change of graphene by controlling the amount of Si and the thickness of graphene were investigated using high resolution photoemission spectroscopy (HRPES), and atomic force microscopy (AFM). The Si nanostructures on graphene show the thickness dependency of graphene, and the size of Si nano-structure reached to 7 nm and 15 nm on the mono and the multilayered graphene after $30{\AA}$ Si evaporation.

  • PDF

Enhanced Performance in Isoindigo Based Organic Small Molecules Field Effect Transistors Using Solvent Additives

  • 박유정;조신욱;서정화
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.392.1-392.1
    • /
    • 2014
  • Isoindigo based small molecules have attracted much attention in the field of optoelectronic devices due to their broad absorbance and high charge carrier mobilitiies. Herein, we investigate the field effect transistor characteristics of a series of isoindigo based donor-acceptor-donor (D-A-D) small molecules containing a variable number of thiophene moieties (named IDT, ID2T, and ID3T) which form pi-bridges between the D and A moieites and a different donor moiety (IDED). In order to improve the carrier mobility, 1-chloronaphthalene (CN) and 1,8-diiodooctane (DIO) as solvent additives were used. The film morphology, crystallinity and optical properties of the materials processed with various concentrations of solvent additives were investigated through atomic force microscopy (AFM), X-ray diffraction (XRD) and UV-vis absorption spectroscopy.

  • PDF

Electro-optic Properties of Holographic PDLC with Various PUA Structures

  • Park, Min-Sang;Kim, Eun-Hee;Woo, Ju-Yeon;Kim, Byung-Kyu
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
    • /
    • pp.437-440
    • /
    • 2002
  • Characteristics of holographic polymer dispersed liquid crystal(HPDLC) were studied according to various matrix materials to improve the electro-optic properties. Various types of polyurethane acrylates (PUAs) have been designed and synthesized. The morphologies of these gratings were measured by atomic force microscopy(AFM) and electro-optic properties were obtained with UV-visible spectroscopy. Real time measurements of grating fabrication have been obtained according to PUA structures. High reflection efficiency was obtained by modifying the molecular structure.

  • PDF

Pulsed Laser Ablation으로 제작한 $C_{60}$ 및 Si 박막의 광학적 특성 분석 (Optical Properties of Silicon Nanoparticles and $C_{60}$ Thin Films Prepared by Pulsed Laser Ablation)

  • 김민성
    • 동력기계공학회지
    • /
    • 제9권4호
    • /
    • pp.118-123
    • /
    • 2005
  • We have investigated the fabrication of Si nanoparticles and $C_{60}$ thin films by pulsed laser ablation. By atomic force microscopy(AFM), the laser-deposited $C_{60}$ thin film was verified to have surface far smoother than the surfaces of films produced by the conventional evaporation method. The Si deposited at a He atmosphere of 0.2 Torr was with about $60{\AA}$ height of the Si nanoparticles, suggesting that it was uniformly deposited. We observed visible green emissions spectra in the $Si/C_{60}$ multilayer films after laser annealing. It is considered that this green emissions is occurred from SiC particles, which is produced reaction of Si nanoparticles with $C_{60}$ by laser annealing.

  • PDF

High aspect ratio 팁의 비접촉모드에서의 측정 (Non-contact mode measurement of high aspect ratio tip)

  • 신영현;한창수
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2006년도 춘계학술대회 논문집
    • /
    • pp.463-464
    • /
    • 2006
  • This paper present experimental results by non-contact mode Atomic Force Microscopy using high aspect ratio tips (HAR-T). We fabricated the carbon nanotube tip based on dielectrophoresis and the carbon nano probe by focused ion beam after dielectrophoretic assembling. In this paper, we measure AAO sample and trench structure to estimate HAR-T's performance and compared with conventional Si tip. We confirmed that results of HAR-T's performance in non contact mode was very superior than conventional tip.

  • PDF

이종 금속 입자를 도핑한 이산화 티타늄박막의 굴절률 및 광학 특성 변화

  • 이재혁;이수민;김선민;서문석;심권우;한종훈;김태근;조진우
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
    • /
    • pp.233-233
    • /
    • 2011
  • 건물 내부의 에너지 효율을 높이기 위해 창호의 단열 효율을 높이는 연구가 최근 큰 주목을 받고 있다. 특히 고굴절률과 저굴절률의 소재를 이용한 다층 박막 구조를 형성하여 높은 광투과율을 유지하면서도 적외선 에너지를 선택적으로 차단하는 창호의 연구가 이루어지고 있다. 본 연구에서는 고굴절률 특성을 가진 TiO2박막을 이종 금속 이온을 sol-gel법을 이용해 첨가 복합화한 후 유리 기판에 스핀 코팅후 열처리하여 성막하였다. 생성된 막은 atomic force microscopy (AFM), 전계 방출 전자현미경, UV-vis를 이용해 각각의 금속 이온에 대한 박막 표면의 형상 변화와 광학적 특성 변화를 확인하였다.

  • PDF

(110)〈110〉 집합조직을 가지는 박막선재용 Ag 기판의 제조 (Fabrication of (110)〈110〉 textured Ag substrate for coated conductors)

  • 임준형;지봉기;이동욱;주진호;나완수;김찬중;홍계원
    • 한국초전도저온공학회:학술대회논문집
    • /
    • 한국초전도저온공학회 2003년도 학술대회 논문집
    • /
    • pp.72-74
    • /
    • 2003
  • We fabricated textured Ag substrates for coated conductor and evaluated the effects of annealing temperature on microstructural evolution, texture formation, and surface morphology. A strong {110}〈110〉 textured Ag substrate was obtained by cold rolling and annealing at 80$0^{\circ}C$: the full-width at half-maximum(FWHM) value of {110}〈110〉 poles was as sharp as 10$^{\circ}$. Surface morphology was evaluated by using Atomic force microscopy(AFM). Root-mean-square(RMS) roughness of the substrate annealed at 80$0^{\circ}C$ was 39.2 nm. The substrate of strong texture and smooth surface, fabricated in our study, is considered to be suitable for use as a substrate for deposition of superconductor films.

  • PDF

Prussian blue가 전착된 indium tin oxide 전극을 이용한 전기화학적 검출기 (An Electrochemical Detector Using Prussian Blue Electrodeposited Indium Tin Oxide Electrode)

  • 이인제;김주호;강치중;김용상
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제54권10호
    • /
    • pp.449-452
    • /
    • 2005
  • We fabricated an electrochemical detector (ECD) to catalyze redox reaction efficiently by electrodepositing Prussian blue (PB) on the indium tin oxide (ITO) electrode. Capillary electrophoresis (CE) and amperometric method were used. We investigated the PB surface properties by topography from atomic force microscopy (AFM). Also PB film thickness calibration with respect to deposition time and voltage was used to get better PB surFace. The PB thin film of dense and smooth surface could catalyze redox reaction efficiently. Comparing with CE-ECD microchip using bare-lTO electrode, proposed CE-ECD microchip using PB deposited electrode has shown better sensitivity by determining the detected peak current from the electropherograms while the concentration of tested analyzes was maintained the same. It is verified that detection limit can be lowered for 0.01 mM of dopamine and catechol respectively.

PU 유도체 단분자막의 온도에 따른 전기 물성과 표면 형상 관찰 (Electrical Properties and Surface Morphology for Temperature in PU Derivatives Monolayers)

  • 서정열;김도균;박재철;권영수
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
    • /
    • pp.458-460
    • /
    • 2000
  • We attempted to fabricate polyurethane derivatives (PU-CN, PU-DCM) LB films by using LB method. Also, we investigated the monolayer behavior at the air-water interface by surface pressure-area ($\pi$-A) isotherms. And, the surface morphologies and the physicochemical properties of LB films were investigated by atomic force microscopy (AFM) and UV-vis spectroscopy, respectively. Also, the electrical properties of polyurethane derivatives LB films were investigated by using the conductivity, the dielectric constant and activation energy. In the surface morphologies, physicochemical, electrical properties of polyurethane derivatives LB films, the properties is different as to the Polyurethane derivatives, it is considered that this phenomena could be described by the difference of lumophore pendant which was adhered at PU main chain.

  • PDF

Disperse diazo black D(DBD) photopolymer의 박막 제작과 이의 물리적 특성에 관한 연구 (A manufacture of disperse diaso black D(DBD) photopolymer thin films and its Physical Properties)

  • 정용환;이호식;변대현;김태완
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1997년도 하계학술대회 논문집 C
    • /
    • pp.1333-1335
    • /
    • 1997
  • We have made disperse diazo black D(DBD) thin films using Langmuir-Blodgett(LB) and vacuum-evaporation technique. Physical and optical properties of the films were investigated. Solution was made with a concentration of $10^{-3}mol/{\ell}$ using chloroform. Moving wall apparatus, (NL-LB140S-MWC) was employed to make the LB films. X,Y and Z-type LB films were manufactured and studied UV/visible absorbance spectra and morphology of surface using atomic force microscopy(AFM). Vacuum-evaporated DB D thin films were made at a pressure of $10^{-5}$ torr. The absorption peaks were observed at 200 and 400 nm in the LB films and vacuum-deposited films. We have also studied photoluminescence spectrum of the DBD films.

  • PDF