Essay on MR.Xiao

Submitted By manyao
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A Practical Guide to

SPM

Scanning Probe Microscopy

A Practical Guide to SPM

TABLE OF CONTENTS
4

I. INTRODUCTION

4

II. HOW AN SPM WORKS

4

The Probe

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The Scanner

5

Scanning: Setpoint, Detector Signal, and Error Signal

6

The SPM Image

6

The Z Feedback Loop

6

Scanning Tunneling Microscopy (STM)

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Atomic Force Microscopy (AFM)

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III. NEAR-FIELD SCANNING OPTICAL MICROSCOPY (NSOM)

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IV. PRIMARY AFM IMAGING MODES

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TappingMode AFM

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Contact AFM

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Non-contact AFM

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Torsional Resonance Mode (TRmode) AFM

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V. SECONDARY AFM IMAGING MODES

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Lateral Force Microscopy

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Phase Imaging

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Magnetic Force Microscopy

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Conductive AFM

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Tunneling AFM (TUNA)

14

Electric Force Microscopy

14

Surface Potential Imaging

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Force Modulation Imaging

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Scanning Capacitance Microscopy

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Scanning Spreading Resistance Microscopy (SSRM)

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Scanning Thermal Microscopy

A Practical Guide to SPM

TABLE OF CONTENTS (continued)
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VI. NON-IMAGING MODES

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Spectroscopy

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Scanning Tunneling Spectroscopy (STS)

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Force Spectroscopy

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Force Volume

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Advanced Force Spectroscopy

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Surface Modification Techniques

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Nanolithography

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Nanoindentation, Nanoscratching, Wear Testing

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Nanomanipulation

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VII. THE SCANNER

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How Scanners Work

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Hysteresis

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Aging

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Creep

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Bow

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VIII. PROBES

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AFM Probes

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Silicon Nitride

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Silicon

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Types of SPM Probes

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IX. TIP SHAPE ISSUES

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Resolution Issues

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X. TYPICAL IMAGE ARTIFACTS

4

I. Introduction

In the early 1980s, scanning probe microscopes (SPMs) dazzled the world with the first real-space atomic-scale images of surfaces. Now,
SPMs are used in a wide variety of disciplines, including fundamental surface science, routine surface roughness analysis, and spectacular three-dimensional imaging — from atoms of silicon to micron-sized protrusions on the surface of a living cell.
The scanning probe microscope is an imaging tool with a vast dynamic range, spanning the realms of optical and electron microscopes. It is also a profiler with unprecedented resolution. In some cases, scanning probe microscopes can measure physical properties such as surface conductivity, static charge distribution, localized friction, magnetic fields, and elastic moduli. Hence, SPM applications are very diverse.
This guide was written to help you learn about SPMs, a process that should begin with a thorough understanding of the basics. Issues covered in this guide range from fundamental physics of SPMs to practical capabilities and instrumentation. Examples of applications are included throughout.
The origins of Veeco SPMs go back to the late 1980s. Since that time, we have maintained strong ties to the academic community and a corporate philosophy that combines technology leadership with a practical-applications orientation, working with customers to demonstrate the ability of our SPMs to meet their needs. We believe that the more you know about scanning probe microscopes, the more likely you will be to choose the best instrument for your work. We want to provide you with the basic facts about SPMs before you make your way through sales literature.

II. How an SPM Works

Scanning probe microscopes are a family of instruments used for studying surface properties of materials from the micron all the way down to the atomic level. Two fundamental components that make scanning probe microscopy possible are the probe and the scanner.
The probe is the point of interface between the SPM and the sample; it is the probe that intimately interrogates various qualities of the surface. The scanner controls the precise position of the probe in relation to the surface, both vertically…