Name: atomic force microscopy for surface mapping
Uploaded: 2023-04-30T12:00:37.000Z
Duration: 1 min 8 s
Channel: JoVE

원자력 현미경 또는 AFM은 나노프로브를 사용하여 이미지를 생성하여 나노미터 해상도의 샘플에 대한 지형 정보를 제공합니다.
광학 현미경은 최대 1000배까지 확대할 수 있지만 AFM의 배율 잠재력은 최대 1,000,000배입니다.
AFM은 고정 표본과 살아있는 표본 모두의 이미지를 생성할 수 있으므로 액틴 역학과 같은 동적 세포 과정을 캡처할 수 있습니다.
AFM 나노프로브는 유연한 캔틸레버 끝에 부착되어 함께 샘플을 스캔합니다. 프로브는 샘플 표면의 윤곽을 따라 위아래로 움직여 캔틸레버를 대체합니다.
AFM의 한 유형에서는 레이저 빔이 캔틸레버를 겨냥하고 움직이면서 레이저의 반사도 움직입니다.
위치 감지 광검출기는 레이저 빔의 편향을 기록합니다.
데이터는 소프트웨어로 전송되어 소프트웨어가 이를 처리하여 샘플 표면의 3차원 이미지를 생성할 수 있습니다.

<ol>
	<li>Casuso, Ignacio, Felix Rico 및 Simon Scheuring. "생물학적 AFM: 우리가 어디에서 왔는지, 우리가 어디에 있는지, 우리가 어디로 갈 수 있는지." 분자 인식 저널 24.3 (2011): 406-413.</li>
	<li>가르시아, 리카르도, 루벤 페레즈. "동적 원자력 현미경 방법." 표면 과학 보고서 47.6-8 (2002): 197-301.</li>
</ol>

원자력 현미경

Atomic Force Microscopy

원자현미경(AFM)은 세라믹, 유리, 폴리머 및 생물학적 표본과 같은 다양한 표본의 지형학적 세부 사항을 분석할 수 있는 스캐닝 프로브 현미경의 한 유형입니다. AFM은 광학 이미징 시스템보다 1000배 이상의 해상도를 제공합니다. AFM에서 생성된 이미지는 3차원 표면 프로필로, 다른 이미징 기술의 평면 2차원 이미지에 비해 이점을 제공합니다.

AFM 프로브

프로브는 모든 AFM 설정의 핵심으로 간주되며 캔틸레버와 팁 어셈블리로 구성됩니다. 프로브는 표본과의 지속적인 상호 작용으로 인해 팁이 마모되기 때문에 이러한 유형의 현미경에서 가장 일반적으로 교체되는 부품입니다. 따라서 프로브 분자 선택은 표본의 특성에 따라 달라집니다. 단단한 표본을 분석하는 데 사용되는 실리콘 프로브는 부드러운 표본을 스캔하는 데 더 적합한 질화 실리콘 프로브보다 더 단단하고 날카롭습니다. 이러한 날카로운 팁은 더 높은 정확도의 분석을 위해 전기화학적 에칭 또는 탄소 나노튜브를 사용하여 생산됩니다.

AFM의 이미징 모드

AFM에서는 프로브 팁과 표본 표면 사이의 상호 작용을 사용하여 표면 지형을 연구합니다. 두 가지 주요 이미징 모드, 즉 접촉 모드라고도 하는 정적 모드와 동적 모드가 있습니다.

정적 모드 또는 접촉 모드에서는 프로브 팁이 표본 표면과 지속적으로 접촉합니다. 팁이 표면 위로 끌리면 표본과 팁 사이의 반발력으로 인해 캔틸레버 굽힘이 발생하고 이것이 기록됩니다. 전체 표본 표면은 래스터 스캐닝이라고 불리는 x축과 y축으로 앞뒤로 스캔되며, 캔틸레버의 수직 이동은 z축을 기록하여 3D 이미지를 생성합니다.

동적 모드에서 프로브는 표본 표면 바로 위에서 진동하여 표면에 가까이 다가가지만 표면에 닿지는 않습니다. 인력과 척력은 팁과 표본 사이의 거리 변화를 결정하여 캔틸레버 진동의 진폭에 영향을 미칩니다. 이 피드백은 표본의 표면 지형을 구성하기 위해 기록됩니다.

원자력 현미경(AFM)은 세라믹, 유리 등과 같은 다양한 표본의 지형 세부 사항을 분석할 수 있는 스캐닝 프로브 현미경 유형의 입니다.

Education

교육

JoVE Core

Cell Biology

세포생물학

Unit 1

제1단원

Visualizing Cells, Tissues, and Molecules

세포, 조직 및 분자의 시각화

KEY TERMS AND CONCEPTS

주요 용어 및 개념

atomic force microscopy for surface mapping

Atomic force microscopy is used to map the surface details of materials. It can examine ceramics, glass, polymers, and biological samples. The method gives far more resolution than an optical imaging system and produces three-dimensional surface profiles instead of flat 2D images.

The probe is the key part of an AFM setup. It includes the cantilever and tip assembly, and it is also the part that is replaced most often. Constant contact with samples wears down the tip, so probe choice depends on the sample being scanned. Silicon probes are stiffer and sharper, which makes them useful for hard samples. Silicon nitride probes are better for softer samples.

AFM tips can be made with electrochemical etching or with carbon nanotubes to improve accuracy. The microscope reads surface topography by tracking how the probe tip interacts with the sample surface. This interaction is recorded as the probe scans across the surface.

AFM uses two main imaging modes. In static mode, also called contact mode, the tip stays in continuous contact with the surface. As it drags across the sample, repulsive forces bend the cantilever, and that bending is recorded. The sample is scanned back and forth in the x- and y-axes, which is called raster scanning, while the vertical motion of the cantilever records the z-axis and builds a 3D image.

In dynamic mode, the probe oscillates just above the sample surface. It comes close to the surface without touching it. Attractive and repulsive forces change the distance between the tip and the sample and affect the oscillation amplitude. That feedback is then used to construct the surface topography.

Atomic Force Microscopy for Surface Mapping

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atomic force microscopy

Atomic force microscopy is used to map the surface details of materials. It can examine ceramics, glass, polymers, and biological samples. The method gives far more resolution than an optical imaging system and produces three-dimensional surface profiles instead of flat 2D images. The probe is the key part of an AFM setup. It includes the cantilever and tip assembly, and it is also the part that is replaced most often. Constant contact with samples wears down the tip, so probe choice depends...

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key terms and concepts

Learn how atomic force microscopy maps surfaces, why probe choice matters, and how contact and dynamic modes build detailed 3D images of samples.

Atomic Force Microscopy for Surface Mapping | JoVE K12

cell biology

JoVE Core Cell Biology illustrates complex cellular processes in easy-to-understand yet comprehensive animated video lessons. This collection focuses on the essential components and functions of cells, including organelles and membranes, cellular transport, and cell energetics. It is complemented by scientist-in-action videos that demonstrate the application of cell biology in real-world research experiments.

Atomic Force Microscopy for Surface Mapping

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