Hitachi SEM
Hitachi SEM Procedure
NTS, 05/14/2014, updated NTS 2014MMDD
[Note: This tool is located at TMI in FNT 2.106 on Main Campus.]
[Note: This tool has a lot of free time. The reservation horizon for this tool is ~one week.]
Prep
Fill in Log when you enter.
Check Pressures.
Sample chamber (SC) pressure: LCD gauge by black scroll ball in box
IP1: gun chamber.
IP2: gun column gauge: on front of box. We want a flashing IP2 LED (signifies what’s being displayed).
Can press mode button to get to IP2 (flashing) on LCD.
[Note: When gun is on, the column and chamber are connected. When you turn on beam, you write down beam on pressure.]
Flash gun tip if needed
This is a cofield emission gun, so it must be flashed every day to clean the tip.
Software should autoflash. If software doesn’t show a message, autoflash worked.
If there’s a message, you might need to manually flash.
To flash: Click Flashing button on left side – Vacc/Current panel. Press flashing and execute.
Panel is opened by clicking Vacc/Current box on left. Beam must be off to flash.
Unload/Load Sample
Put on gloves.
Prepare area for sample holder. Take holder mount out of black box on table.
Do not touch gold part of rod once it’s out.
Can touch silver part, but minimize this.
Remove sample holder from SEM.
There is a guide on the box.
Pull straight out, rotate CW slightly, pull straight out, rotate CCW, you’ll hear a sound.
There are hard stops. Don’t be too forceful.
Press and hold Air button til it lights to vent. Then wait till LED is off.
Pull out rod.
Place rod onto holder.
There are certain tools to use with the rod to keep it clean.
Use metal fine sharp curved tweezers for Al stub (STD holder), and white tool for stub lock on neck of holder.
Max sample size is 9 x 5 mm.
Double sided carbon tape provided.
There are little Al stubs for sample mounts.
Remove stub from rod using white tool. Pull little lock thing on neck with an up motion at the end.
Slide rod back a little to let stub fall out.
Get stub if needed, without touching gold part of rod.
Place sample on stub with double sided tape and sharp tweezers.
Use sample height scale to find sample height (closest #).
Don’t pass 2.0, 0.0-1.0 is best. Numbers are mm.
Put stub into holder with metal fine sharp curved tweezers.
Lock stub into place with white tool.
Check it’s locked by lifting up rod slightly and turning it over, then tapping on handle.
TEM rod: Remove Al piece from rod using carbon tipped tweezers and with plastic lid under tip.
Use tweezer tips to pull back little lock near tip and Al piece will fall out (onto lid).
Put in TEM grid with metal tweezers (sharper)
Put back Al piece
Load holder into SEM
There is a guide on the box.
Lineup pin on rod and push in til it stops.
Press and hold Evac button.
With a firm grip, wait for High Vac LED to blink, which is 5-8 seconds.
Don’t wait for it to go solid. If it does, you must re-evacuate and go from there. Goes solid in 10-20 seconds post-blinking.
Turn CW and don’t let it get sucked in fast (push in if it doesn’t get sucked in), turn CCW and don’t let it get sucked in fast (push in if it doesn’t get sucked in).
The rod is now loaded and the pressure should be going down.
Check LN2 level.
Fill with dewar if needed, tank next door. Can work without LN2 if you can’t get any.
Software Prep
Stage check before turning on the beam; check sample holder and sample height
Click stage tab at right. Click restriction and select holder type and height.
Enter sample height. Height for TEM grids is 0.0.
Don’t mess with other numbers. Press close when done.
Beam check.
Click SEM tab (on right). Select SE under current dropdown menu (secondary electron).
Under OPE condition, make sure probe current is normal. Analysis is for EDS.
Check V-I: Vacc/I window on left.
Choose Vacc and Current.
Smaller Vacc (power) for soft materials. More for heavy stuff, e.g. Au or Pt. Can change Vacc during use by clicking on it and changing number.
Voltage: 1 kV or less to 30 kV max.
Current is dependent on sample resistance to beam damage. 10-20 uA might be good.
Mag check: check beam magnification, make sure it’s low: < 2k
Use zoom knobs on hard panel, big knob on left to fix zoom if needed.
Turn on beam: press On in upper left corner. HV is now on.
If there is a warning, read the first few lines and act accordingly.
Press OK or fix problem/setup.
Check brightness and contrast to setup view, on hard panel (upper right), then focus
Can also click ABCC for auto, on top ribbon (in middle)
Focus using hard panel knobs (lower right), do not use AFC.
Software should start in high zoom. To go to Zoom < 1.3k, press H/L (High/Low) button at top center. Zoom is 100 or less to ~10k in low setting, and >500k in high.
Scan speed control at top left via different detectors.
Click on button to select a detector and/or change speed, there are two speeds for each.
21c. Want fast speed for alignment, perhaps TV1 or Fast2.
21d. Customize detectors: right click on any of them and put dot in position you want detector at in buttons.
Beam alignment prep: be in High mode, choose a feature, zoom in a little (to ~3k). Focus, zoom into 40-60k Mag.
Beam alignment
Press Align at top middle, window pops up with list of things to do. Do beam align first, then aperture align.
Beam align: click beam align. View pops up, you want white stuff in center. Use multifunction knobs in lower middle of hard panel to get white stuff centered.
Aperture align: click aperture align on alignment window, will see wobbly view. Use knobs to minimize wobble. Minimize wobble in x and y. There will still be wobble in focus/Z.
Stigma aligns: click Stigma align X and minimize wobble. Click Stigma align Y and minimize wobble.
Click Close when done.
Can re-align during real use (looking at features of interest) with hard panel knobs.
Might have to redo part of this if you go to magnification >300-500k.
For high Mag (~ > 300k): If when you focus back and forth there is streaking (stretching of features in one direction), needs more alignment to get better image. Can use stigmator knobs on hard panel as well.
To do TEM, BF-STEM: Change current on right to bright-field.
Units on scale bar are for whole scale bar, each tick is a tenth of that number.
Can select just part of the screen to get a fast response to changes in focus, stigmation, etc. and to protect part of sample near where you improve focus.
To do so, press Red (reduced area detector).
Click any sensor to end selective screen selection.
Use
To acquire images:
Single frame: put into slow1 or 2 mode and press 1280 button (upper middle)
Real-time averaged image: put into TV1 or 2 mode and press 1280 button
[Note: Make yourself a folder in the D:\Image folder. Put S-5500 before your name (e.g. S-5500-nsheehan, or like other folders).]
Capture image window pops up. Click save if desired (left of window) or wait til you capture multiple and are done. Select desired images then click save and save into your folder.
To improve images: Press Run in upper left, press Slow1 then 1280 to use slow capture.
Click black triangle above 1280 to look at capture settings. 16 frames is standard.
To add notes/measurement, go to Utilities tab at right. Add stuff. To remove, click All and Clear.
Can press freeze to shutter beam and step out for a minute.
Can select screen mode: Full, Small, Dual (two detectors)
DF-STEM: brightness ~proportional to atomic mass [DF or BF?]
Finish use
Press Off/Home in upper left. Stage moves, press OK. Hear a beep. Upper right should have a home button and green crossbar with words beam.
Sample is at home. Proceed to unload (Steps 4-8).
Replace sample holder into chamber properly before leaving (Step 12).
Fill in rest of log as needed.
EDS Usage
EDS program is Esprit 1.8 on Computer Two
Open and Login
I’m assuming you have already done Steps 1-26 or Steps 1-33 above)
That means you have loaded samples and have the target area and focus all set up
Click Acquire to acquire spectrum for area in view
Make sure Autoscale X and Y Once is selected (A button, lower right)
Element selector button is at center right
Double click elements to see more info
SEM kV limits peaks EDS can see
Need SEM kV to be twice peak you want to see
Select elements
Click Acquire again to stop acquiring spectrum
Click little arrow next to Acquire to see acquire settings, shouldn’t need to change
Settings: Measuring time, 30, 100, 200000, manual, blah; Cyclic acq., 10, 0
When adjusting kV, re-align and focus beam
Change OPE condition current to Analysis
Click Acquire on Esprit again
Want spectrometer counts to be > 1k
To save, click Export button at center right (double arrows)
41b1. Save as Excel File (Spectrum, at top) or Image (Graphic, at bottom).
41b2. Pay attention to file type
41c. Spectrum is for area in view
41d. Move and/or zoom out to change area
42a. To find position of elements on sample, click Objects
42b. Four types of ‘scan’, click Point
42c. Need to get a sample image
42d. Go to Image Scan and click New
42e. Wait or press New/Stop when good enough
43a. Click Mapping
43b1. Adjust rectangle as desired
43b2. Don’t want box to be too big, costs time
43c. Periodic table on left pops out so you can select elements
43d. Click Acquire next to Map data
43e. Go to Spectrum tab to see spectrum and learn more, and see which peaks it uses
43f. Click Acquire when satisfied
44a. Probably want to focus on/save individual element maps
44b1. There’s an export button for the Image scan, Map data (composite map), and Elemental maps.
44b2. Each of these things can be exported as Excel file or Graphic file.
44c. Can export single element map graphics by checking/unchecking submaps at bottom
45a. When satisfied with saving data, click Point scan and can do a number of things.
45b1. Adjust/move box and repeat. Click OK when it says delete data, make sure your stuff is saved.
45b2. Go to point scan and ?
45c. Zoom change or move sample and repeat Steps 39-44
45d. When done, close Esprit and select yes