operation of the s4700 fesem

Operation of the S4700 FESEM

Quality SEM analysis is a matter of three factors

60% Sample- Preparation or type of sample30% Knowledge of the operator10% Type of instrument

Hitachi S4700 Instrument was installed in August of

1999 Has EDS, Backscatter, EBSD

capabilities High resolution imaging, up to

500,000X Low voltage imaging, down to 0.5kV

Basic Operation of the S4700

Each time you use the scope you need to fill the LN2 trap to the side of the scope.

Degas not Degauss If you are the first to

use the scope then you must “Degas” the lower aperture

This is to clean the lower aperture.

Flip the switch located in the left of the instrument panel on the column down from “Heating” to “DEGAS”

Software

Software

You will be given a user account and you You will be given a user account and you will set up a password that will be will set up a password that will be changed each time you use the scope. changed each time you use the scope. The initial logo should appear once you The initial logo should appear once you log inlog inIf it does not then open the SEM software If it does not then open the SEM software from the FE-SEM icon on the desktopfrom the FE-SEM icon on the desktop

This is the operating window of the 4700 software.

All operation can be done with the mouse or with the help of the small control panel.

Log Book

The microscope operating conditions will be written in a log book. These include the readings of the ion pumps, Ip1, Ip2, Ip3, the Vext, Ie, Vacc, date, user name, advisor and flash information if applicable

Set the HV using the HV control window and the drop down Vacc menu. HV’s between 0.5-30 kV are available

kV selection for a sample should be based on the type of analysisSamples that are non-conductors such as ceramics, glass, some oxides should be run at lower kV due to charging effects, which can cause problems with imaging.

Samples that are conductors such as metals can be run at higher kVs but might not be necessary.

Check the sample to see if the desired results are there at lower kVs. There is no need to blast the sample if the desired results can be obtained at a lower voltage.

Remember the 2X rule for doing EDS on samples.

Insert Sample into Sample Exchange chamber

Once the sample has been correctly prepped, it should be screwed to the end of the insertion rod.

DO NOT BEND THE INSERTION ROD WHEN MOVING THE SAMPLE!

Chamber Scope The S4700 is fitted with in

infrared camera. This allows the user to see inside the sample chamber and avoid bumping into detectors when inserting samples and moving the stage

Chamber scope is turned on prior to inserting the sample into the sample chamber

On switch

Sample Chamber When the S.E.C. light

on the front panel turns green open MV1 on the sample exchange door and allow the sample to be pulled into the sample chamber by the vacuum, watch on the chamber scope.

Column Setup As the sample

chamber pumps down, use the Column Setup for the type of SEM examination

The S4700 has 6 operation modes for the column

Ultra High Resolution

Analysis

Normal

Long WD

Magnetic

UHRA

Working distance – True working distance and can be set.

Condenser lens 1 - Default is 5, smaller numbers are bigger spot size, range is 1-16.

DeGauss- To degauss the column

Select Detector – Mixed for analysis and imaging

Upper for high resolution

Lower for analysis and samples that have slight charging

HV On Turn on HV in the HV window when

the sample chamber is at L X 10-3 Check Ip3, if it is 1 X 10-5 then DO

NOT OPERATE Note the Vacc, Ie and Vext and put in

Log book

Imaging Beam alignment Select scan speed Locate area of interest Go to High Mag mode Aperture alignment Stigmate Final Focus Brightness and contrast Capture image

Beam alignment Focus the image Click on “Beam

alignment” in the “Alignment” window

Use the left knobs on control panel to adjust the beam in the middle of the target.

Will have to been done multiple times throughout operation.

Alignment window

Beam align button

Beam

Move the beam to the center of the target

Can be done in the grid window using the mouse

Select scan speed 6 scan speeds Fast 1 and 2 – Frame averaging Can

be set in the “Signal Processing Window”

Slow 1-4 – are raster scan in seconds and are preset

5 is a reduced area scan used to aid in focusing in a smaller area

Scan Speed buttons

1 2 1 2 3 4 5

Signal Processing window

Locate area of interest Orient the sample

using 5 axis stageX, Y, Z, Tilt, and rotation

Move the sample to locate an area of interest, with trackball, click and drag, stage arrows, change x, y, z, tilt, and rotate

Trackball Mouse

Click and drag either the stage or the beam.

This button for the beam. Blue hand cursor

Stage arrows

This button for the stage. Yellow hand cursor

Stage Control

Change x and y positions

Rotate

Z position

Tilt

Go to High Mag mode Use the Low Mag mode to locate an area of

interest Low Mag mode is 30-10,000x and can not be

used for EDS Use High Mag mode for EDS and imaging High Mag mode is 250x to 500,000x Not all samples can be imaged at 500,000x Typical magnification is 25,000x to 250,000x

Aperture alignment Check the beam alignment Increase the mag, best done at the highest

resolution Click on the “Aperture Align” in the

“Alignment” window Use X and Y alignment knobs on control

panel Good alignment has little or no X or Y

movement. Image should pulse or rotate

Low Mag/High Mag mode

Aperture Alignment

Stigmate Refocus the image after Aperture alignment If the image skews out of focus it is out of

sigmation. Use knobs on the left of the control panel Y Stigmate first, X Stigmate, fine focus then

check Y and X stigmation again Gross movement of the image indicates the

sigmators need alignment Use the Alignment window and proceed with

sigmation alignment in the same manner as aperture alignment.

Stigmation alignment

Final Focus Select a slow scan speed to increase

resolution Refocus image

Brightness and contrast After focus do an “Auto Brightness

and Contrast” Brightness and Contrast can also be

adjusted manually with the “Brightness and Contrast” monitor button

Auto Brightness and Contrast Button Brightness

and Contrast Monitor Button

Capture Image Select image capture options in the “Capture

Image Window” Capture an image with the “M” button on the

main window. Image will be temporarily saved to a

“Capture Image Window” “Capture Image Window” will appear, use the

“Disk Icon” to save the image. All Images are to be saved on the D drive At completion images should be moved to the

internet or recorded on a CD.

Capture Resolution-Change the size of the captured image

Capture speed of the image- Frame averaging or slow scanning speed

Capture Image WindowRed “Saved”, image has been saved

Red number in upper left corner is the active image

Yellow number in the upper left corner is the next window to be occupied

Disk Icon for saving the image

Saved

Use the SEM Data Manager to view your images

Blurred Images Beam Alignement Aperture Alignement Stigmantion Coarse Focus Fine Focus Building Vibrations Stray Electric Fields Tip Noise

Hints on Stigmation Check Stigmation Alignment Focus best possible image with fine

focus with no “Skewing” Y stigmate X stigmate Fine Focus

Tip Noise Flash Tip Open the HV Window Select “Flash” Click on Flash and watch the Ie number

quickly appear in the window Note this number in the Log Book DO NOT operate if the Vext has changed 1.2

more than the most recent Flash Ie

Ie and Vext Ie changes rapidly after flashing “SET” a new Vext as the Ie drops Best working conditions are at an Ie

of >9 If Ie goes up to 12 STOP operation

and flash

Ie can be changed, most common is 10 micro Amps

Flashing button

The “On” button becomes a “SET” Button when HV is on