• Title, Summary, Keyword: Near-field scanning microscopy

Search Result 54, Processing Time 0.035 seconds

Polarization State of Scattered Light in Apertureless Reflection-mode Scanning Near-Field Optical Microscopy

  • Cai, Yongfu;Aoyagi, Mitsuharu;Emoto, Akira;Shioda, Tatsutoshi;Ishibashi, Takayuki
    • Journal of Magnetics
    • /
    • v.18 no.3
    • /
    • pp.317-320
    • /
    • 2013
  • We studied the polarization state in an apertureless scanning near-field microscopy (a-SNOM) operating in reflection mode by using three-dimensional Finite-difference Time-domain (FDTD) method. As a result, the electric field around tip apex in the near-field region enhanced four times stronger than the incident light for ppolarization when the tip-sample separation was 10 nm. We find that the p- and s-polarization state is maintained for the scattered light when the probe is perpendicular to the sample. When the probe is not perpendicular to the sample, the polarization state of scattered light will rotate an angle that equals to the inclination angle of probe with p-polarization illumination. On the other hand, the polarization state will not rotate with s-polarization illumination.

A Study on the Coupling of a Flanged Parallel-Plate Waveguide to a Slit In a Nearby Conducting Screen for Near-Field Scanning Microscopy

  • Lee, Jong-Ig;Cho, Young-Ki
    • Journal of electromagnetic engineering and science
    • /
    • v.9 no.2
    • /
    • pp.105-109
    • /
    • 2009
  • The problem of electromagnetic coupling between a slit fed by a flanged parallel-plate waveguide(PPW) and a slit in an infinite nearby conducting screen parallel to the flanged ground conductor is studied as a simplified problem for a near-field scanning microscopy(NSM). The method of moments isused to solve the coupled integral equations for the electric field distributions over the slits. The performance of the proposed apparatus as an NSM is tested by examining the effects of some geometrical parameters on the equivalent slit admittance and coupled powers through the slits.

Narrow Resonant Double-Ridged Rectangular Waveguide Probe for Near-Field Scanning Microwave Microscopy

  • Kim, Byung-Mun;Son, Hyeok-Woo;Cho, Young-Ki
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.1
    • /
    • pp.406-412
    • /
    • 2018
  • In this paper, we propose a narrow resonant waveguide probe that can improve the measurement sensitivity in near-field scanning microwave microscopy. The probe consists of a metal waveguide incorporating the following two sections: a straight section at the tip of the probe whose cross-section is a double-ridged rectangle, and whose height is much smaller than the waveguide width; and a standard waveguide section. The advantage of the narrow waveguide is the same as that of the quarter-wave transformer section i.e., it achieves impedance-matching between the sample under test (SUT) and the standard waveguide. The design procedure used for the probe is presented in detail and the performance of the designed resonant probe is evaluated theoretically by using an equivalent circuit. The calculated results are compared with those obtained using the finite element method (Ansoft HFSS), and consistency between the results is demonstrated. Furthermore, the performance of the fabricated resonant probe is evaluated experimentally. At X-band frequencies, we have measured the one-dimensional scanning reflection coefficient of the SUT using the probe. The sensitivity of the proposed resonant probe is improved by more than two times as compared to a conventional waveguide cavity type probe.

Theoretical and Experimental Investigation on the Probe Design of a Ridge-loaded Slot Type for Near-Field Scanning Microwave Microscope

  • Son, Hyeok-Woo;Kim, Byung-Mun;Hong, Jae-Pyo;Cho, Young-Ki
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.5
    • /
    • pp.2120-2125
    • /
    • 2015
  • In this paper, a rectangular waveguide probe with a ridge-loaded straight slot (RLSS) is presented for a near-field scanning microwave microscope (NSMM). The RLSS is located laterally at the end wall of the cavity and is loaded on double ridges in a narrow straight slot to improve the spatial resolution compared with a straight slot. The probe consists of a rectangular cavity with an RLSS and a feed section of a WR-90 rectangular waveguide. When the proposed NSMM is located at distance of 0.1mm in front of a substrate without patches or strips, the simulated full width at half maximum (FWHM) of the probe improve by approximately 31.5 % compared with that of a straight slot without ridges. One dimensional scanning of the E-plane on a sample under test was conducted, and the reflection coefficient of the near-field scanning probe is presented.

A Study on the Coupling of a Flanged Parallel-Plate Waveguide to a Nearby Conducting Strip from the Viewpoint of Near-Field Scanning Microscopy (근접주사현미경의 관점에서 플랜지된 평행평판 도파관과 근접도체스트립과의 결합에 관한 연구)

  • Lee, Jong-Ig;Ko, Ji-Hwan;Cho, Young-Ki
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.13 no.11
    • /
    • pp.2260-2266
    • /
    • 2009
  • In this paper, the problem of electromagnetic coupling between a slit fed by a flanged parallel-plate waveguide (FPPW) and a nearby conducting strip parallel to the slit is studied as a simplified problem for a near-field scanning microscopy (NSM). The characteristics of the FPPW are investigated from the results for the variations of the equivalent slit admittance, the reactive powers near the slit inside and outside the FPPW, the magnitude and phase of the voltage reflection coefficient of the TEM wave. The performance of the proposed apparatus as an NSM is tested by examining the effects of various geometrical parameters such as guide height, slit width, strip width, distance between slit and strip, and the ratio of slit width to guide height on the magnitude and phase of the voltage reflection coefficient of the TEM wave. From the results for the voltage reflection coefficient against the strip offset from the slit, it is found that a slit in the FPPW with smaller guide height gives higher scanning resolution and the phase variation is more sensitive than the magnitude variation.

Nondestructive measurement of surface resistance of indium tin oxide(ITO) films by using a near-field scanning microwave microscope (근접장 마이크로파 현미경을 이용한 ITO 박막의 표면저항의 비파괴 관측 특성 연구)

  • Yun, Soon-Il;Na, Sung-Wuk;You, Hyun-Jun;Lee, Yeong-Joo;Kim, Hyun-Jung;Lee, Kie-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.137-141
    • /
    • 2004
  • 저항특성이 다른 ITO박막의 구조특성과 표면특성을 XRD와 AFM(atomic force microscopy), SEM(scanning electron microscopy)을 이용하여 관측하였다. 접촉방식인 4단자 법을 사용하여 ITO박막의 표면전기저항을 측정하였다. 관측된 구조 및 표면특성을 바탕으로 비파괴 비접촉방식을 이용한 근접장 마이크로파 현미경을 이용하여 얻은 ITO박막의 표면저항특성과 비교 연구하였다.

  • PDF

Observation of Morphology, Surface potential and Optical Transmission Images in the Thin Film Using SPM (SPM을 이용한 박막의 모폴로지, 표면전위와 광투과이미지 관찰)

  • Shin, Hoon-Kyu;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.327-330
    • /
    • 2000
  • The scanning Maxwell-stress microscopy (SMM) is a dynamic noncontact electric force microscopy that allows simultaneous access to the electrical properties of molecular system such as surface potential, surface charge, dielectric constant and conductivity along with the topography. The Scanning near-field optical / atomic force microscopy (SNOAM) is a new tool for surface imaging which was introduced as one application of the atomic force microscope (AFM). Operated with non-contact forces between the optical fiber and sample as well as equipped with the piezoscanners, the instrument reports on surface topology without damaging or modifying the surface for measuring of optical characteristic in the films. We report our recent results of its application to nanoscopic study of domain structures and electrical functionality in organic thin films by SMM. Furthermore, we have illustrated the SNOAM image in obtaining the merocyanine dye films as well as the optical image.

  • PDF

Self-focusing and Structure Measurement of $a-As_2S_3$ Using Near-field Scanning Optical Microscopy (근접장 광학 현미경을 이용한 $a-As_2S_3$ 박막에서의 자체집광 및 구조변화 측정)

  • 전태종;정희성;조규만
    • Proceedings of the Optical Society of Korea Conference
    • /
    • /
    • pp.122-123
    • /
    • 2002
  • 능동적으로 안정화시킨 반도체 레이저의 빛살되먹임을 이용한 근접장 광학현미경(Near-field Scanning Optical Microscope)을 이용하여 칼코게나이드계 유리인 a-As$_2$S$_3$에서 광조사에 따른 자체집광 현상과 구조변화를 관찰하였다. 여러 비선형 광학현상 중 광 커르 효과(Optical Kerr effect)에 기인하는 자체집광(Self-focusing)은 광범위하게 연구되어 왔다. (중략)

  • PDF

Recording and Retrieving of Angular Multiplexed Near-field Holograms (근접장 홀로그램의 각도 다중화 저장 및 재생)

  • 김경염;이병호
    • Proceedings of the Optical Society of Korea Conference
    • /
    • /
    • pp.60-61
    • /
    • 2001
  • We present our experimental results on the recording and retrieving of multiplexed near-field holograms using near-field scanning optical microscopy (NSOM) and a conventional rectangular-parallelepiped or cubic photorefractive crystal. Experimental results show that we can get the angular selectivity comparable with that of the volume hologram and the retrieved spot size was smaller than the Rayleigh's limit. The results also show that the angular selectivity and the retrieved spot size are strongly dependent on the recording distance between the object and the recording medium.

  • PDF