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Tool expert: Prof. Shun-Tun Yen

Technician ： Ms. Lien-Chu Chen

高解析度場發射掃描電子顯微鏡暨能量散佈分析儀 Scanning Electron Microscope (S-4700I)

Tool name

Chinese name： 高解析度場發射掃描式電子顯微鏡暨能量散佈分析儀

English name： High-Resolution Scanning Electron Microscope

& Energy Dispersive Spectrometer Acronym：

SEM & EDS

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Tool info

manufacturer ： Hitachi

model ： S-4700I

Date of purchase ： May 1st, 1999.

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Features

SEM： High-resolution inspection of devices, thin films,

and cross-sections.

EDS： Energy-dispersive spectroscopic analysis of

material or contamination composition on a desired spot.

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Tool spec

E-gun source ： Cold cathodic E-gun

Operation voltage ： 0.5kV~30kV

Sample size ： 25mm diameter x 25mm(t)

Working distance ： current setting at 12mm

resolution ： 1.5nm (at 15kV) or 2.5nm (at 1kV)

Highest mag: 500K(depending on the sample ）Resolution of secondary electrons:1.5nm(below 15kV)

EDS could provide qualitative/quantitative atomic （ B5~U92 ） and elemental distribution analysis across the whole energy spectrum .

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Principles of SEM (Scanning Electron Microscope)

Tool introduction E-gun: electron source

Electromagnetic lens: for altering electron path direction

Optical focus system

Principles Electron migration path

Interactions between electrons and matters

Vacuum necessity and specimen chamber structure.

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Vacuum system

Good vacuum is prerequisite for obtaining high quality images in SEM

The vacuum is maintained by the following pumps :

Electron chamber and electromagnetic lens: 3 ion pumps

S.C.-Specimen Chamber: cycled-water chilled diffusion pump and rough pumping by a rotary pump

S.E.C.- Specimen Exchange Chamber: Rotary pump

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Operation procedures

Procedures ： SEM basic SOP( please click)

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Tips

Good sample conductivity：The sample should be highly conductive to ensure sufficient

detection of secondary electrons and clear images. Pt or Au capping can help improve the conductivity. However, too thin the capping does not help a lot and too thick of it might cover the inspected area.

For less conductive samples such as Si or SiO2, it is

recommended to attach the carbon tape on the sample front side after Au deposition. This way, electrons are attracted toward the stage and only a slit is available for secondary electrons.

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Tips

Avoid vibration：For high-mag inspection, make sure the sample is firmly

attached and the stage is well fastened. Stage lock feature can be enabled to reduce the vibration caused by external factors.

(Once stage lock is enabled, tilt cannot be adjusted)

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Tips

Vacuum ： the lower the better

Accelerating voltage: higher voltage can lead to better images. The maximum voltage a sample can withstand depends on its own properties. Too high the voltage might damage the sample and result in pollutant generation.

Discretion, attention, and patience are highly appreciated.

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SEM Pictures—taken by Ms. Yue-Ting Chen

Gold particles with 10K mag

500nm for each spacingmagNCTU NFC Yue-Ting Chen

SEM Pictures—taken by Ms. Yue-Ting Chen

Surface of gold particles is clear with 150 K mag

30nm for each spacing

magNCTU NFC Yue-Ting Chen

Surface of gold particles with 250 K mag

20nm for each spacingmag

SEM Pictures—taken by Ms. Yue-Ting Chen

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Surface of gold particles with 300 K mag

10nm for each spacingmag

SEM Pictures—taken by Ms. Yue-Ting Chen

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Surface of gold particles with 400 K mag

10nm for each spacingmag

SEM Pictures—taken by Ms. Yue-Ting Chen

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Surface of gold particles with 450 K mag

10nm for each spacing

mag

SEM Pictures—taken by Ms. Yue-Ting Chen

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Surface of gold particles with 500 K mag

10nm for each spacing

mag

mag

SEM Pictures—taken by Ms. Yue-Ting Chen

10nm for each spacingNCTU NFC Yue-Ting Chen

The following pictures are taken by students from various affiliations.

Through SEM, we can share our own skills and excellent pictures.

SEM Pictures—taken by Ms. Yue-Ting Chen

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Carbon nano tube

SEM Pictures—taken by a student

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Zno nanowire

SEM Pictures—taken by a student

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MOSFET device

SEM Pictures—taken by a student

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High-K material

SEM Pictures—taken by a student

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Material for high-frequency devices

SEM Pictures—taken by a student

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High-speed device

SEM Pictures—taken by a student

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SiO2 nanoparticle-fixing substrate

SEM Pictures—taken by a student

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polymer micelles

SEM Pictures—taken by a student

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Carbon nano tube

SEM Pictures—taken by a student

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CeO nano cube

SEM Pictures—taken by a student

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Cu

SEM Pictures—taken by a student

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photonic crystal

SEM Pictures—taken by a student

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Nanoscale linewidth

SEM Pictures—taken by a student

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Surface analysis

SEM Pictures—taken by a student

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Surface analysis of Ti

SEM Pictures—taken by a student

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GaN surface roughening for blue light LED

SEM Pictures—taken by a student

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Oxide-based nanowire

SEM Pictures—taken by a student

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Nylon film

SEM Pictures—taken by a student

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Blocking layer deposited via PECVD on Pet film

SEM Pictures—taken by a student

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fiber

SEM Pictures—taken by a student

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Conclusion

Please cherish this multi-functional SEM !!

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