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IF IN DOUBT ASK Mick: 255-0650 Mick: 255-0650 IF IN DOUBT, ASK FEI FIB Focused Ion Beam Operating Manual Part 2

FEI FIB Focused Ion Beam · 2017. 3. 2. · FIB image X-Y controls: • L-R arrows move opposite direction FIB image Z controls: • Up-down arrows move U-D 10.20 How to prepare a

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  • IF IN DOUBT ASKMick: 255-0650Mick: 255-0650 IF IN DOUBT, ASK

    FEI FIB

    Focused Ion Beam

    Operating Manual

    Part 2

  • IF IN DOUBT ASKMick: 255-0650

    TEM specimen prep in FIB• The general process flow is

    shown at left.

    • In these instructions CO = “Click On”

    • These instructions assume there are grids already mounted in the row holder and that the row holder is on the shuttle (i.e. not using flip stage). If you are not sure about this see Mick.

    • The portion of these instructions referring to Automatic Cutout assumes AutoG2 TEM software is installed

    First protection layer• If your area of interest is near the

    surface (

  • IF IN DOUBT ASKMick: 255-0650

    • Launch. AutoTEMG2

    • CO Create and make a file for info

    • Select 15X10 thick liftout

    • Basic Tab Settings:1. Width to15u 2. Thickness to1.5u3. Depth to 10u4. Ensure Skip Fiducials is not checked

    • Advanced Tab Settings:1. Rough mill current to 9300pA 2. Cutout width to 0.8μ 3. Deposition height to 1.5 μ 4. Angle correction to 0 5. Depth correction to 1

    • Process Control Settings:1. Perform rough mill step2. Do cutout is optinal3. Generally do not perform final milling

    step

    • A new window has shown up with a yellow box in it. Use beam shift controls to center Pt layer (just put down by E-Beam) inside yellow box. CO Mill Fiducials

    • CO Ground to put grounding layer down

    • CO Finish

    • Confirm that both the 9.3nA beam and 0.28nA are focused outside your area of interest, lower beam current to 0.93pA and move back over area of interest.

    • CO Run

    How to use the Automated procedure10.20

  • IF IN DOUBT ASKMick: 255-0650

    If routine fails it is probably because:1. The I-Beam is not focused correctly at 9.3 A or 0.28 nA, and

    it cannot recognize the fiducial marks. Move to a sacrificial area on your sample well away from your region of interest and refocus the I-Beam at 9300pA. Then pause I-Beam, move back to your region of interest using the E-Beam, and click on Run again. Bottom side must start first.

    2. The Sharpie coating is too thick – try a region with thinner Sharpie or take sample out and re-coat with thinner Sharpie.

    How to use the Automated procedure (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    How to prepare a TEM sample manually

    Check that a principal crystallographic plane is oriented parallel to your cut, if important.

    Set eucentric height;

    E-Beam coating (If desired)

    • Set stage to 0 degrees for E-Beam deposition.

    • Set E-Beam to 2keV and 3.4nA and check cross-over, refocus, stigmate. Set deposition window to 25μ (x) by 3μ (y) by 50nm (z).

    • Deposit E-Beam platinum.

    • Remove Pt needle

    • Lower mag to 2000X; center the Pt coating mechanically and ensure the electronic shifts of the E-Beam are centered

    .• Set E-Beam to 5keV, 1.6nA

    10.20

    It is important to recognize that proper TEM preparationconsists of “A thousand little tricks” all of which cannot possiblybe explained in this manual. Here are some very BASIC stepsto take when preparing a TEM sample.

  • IF IN DOUBT ASKMick: 255-0650

    • Turn on I-Beam and set it to 30keV, 0.28nA

    • Check that I-Beam is focused and stigmated and centered on the same spot as the E-Beam, keep mag low.

    • Take snapshot of ion image

    • Set I-beam deposition to 25um by 3um by 0.5 to 1.0 um thick. If an e-beam deposition was done, then cover over same area as e-beam deposition.

    10.20 How to prepare a TEM sample manually (continued)

  • IF IN DOUBT ASKMick: 255-0650

    • Set up Regular cross-section. The width (Y or vertical direction on screen) should be about two times greater than the Z depth.

    • Start with 9.3nA beam and go close to the final edge but leave about 1-2 um for removal with a lower current ion beam.

    • Lower the beam current to 2.8nA and tilt the sample to 54 degrees. Using a regular cross-section remove remaining material up to the edge of the Pt.

    • Lower beam current to 0.92nA and cut about 0.5 microns into the Pt.

    10.20 How to prepare a TEM sample manually (continued)

  • IF IN DOUBT ASKMick: 255-0650

    • Repeat process for the other side.

    • When you are finished the sample should look like below, except without the fiducial marks.

    • Final thickness before liftout should be about 1.5uM

    How to prepare a TEM sample manually (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    • Tilt the sample to 0 degrees.

    • Set up three milling boxes as shown

    • Beam current 0.92nA or 2.8nA

    • Mill until all the way through on all rectangles

    • Sample should look like sample on following page.

    How to prepare a TEM sample manually (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    • After cutting through attach the Omniprobe needle as follows:

    • Rotate scan in I-column 180 degrees.

    • Lower I-Beam current to 28pA

    • Set mag to 100X

    • Insert OP – visible around 100X

    SEM image X-Y controls:• L-R arrows move L-R,

    FIB image X-Y controls:• L-R arrows move opposite direction

    FIB image Z controls:• Up-down arrows move U-D

    How to prepare a TEM sample manually (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    • Switch ion beam to 0.92nA or 2.8nA and cut off remaining support beam

    • Reduce beam current to 0.93nA and lift lamella out

    How to prepare a TEM sample manually (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    • Move sample to less than 0.5um from post and attach using a 93pA ion beam.

    How to prepare a TEM sample manually (continued)10.20

  • IF IN DOUBT ASKMick: 255-0650

    Switch to a 0.92nA beam and cut off the Omniprobe needle and retract it.

    • Tilt to 52 degrees.

    • Using a 30 keV ion beam at 0.92nA and a regular cross-section to mill away just enough material to establish a flat surface.

    • Remain at 52 degrees and rotate the stage 180 degrees and mill the other side. Now you should have two very parallel faces.

    10.20 How to prepare a TEM sample manually (continued)

  • IF IN DOUBT ASKMick: 255-0650

    • After milling the two parallel faces, tilt to 54 degrees. Lower the voltage to 5keV and 47 pA continue, using a Regular cross-section, to thin the lamella. Set Z depth to about 0.25 um. Repeat several times to create a “ledge” where the bottom of the sample is thicker, the top is thinner.

    • To mill the other side rotate the sample 180 degrees, but do not change tilt angle.

    • Repeat many times and gradually thin the sample. When the platinum layer just begins to get thinner, switch to Cleaning cross-section.

    • When the platinum is about 0.25 um tall, lower the voltage to 2keV and the current to 89pA, re-align beam, increase the angle to 56 degrees, and use a Cleaning cross-section to polish further.

    • If possible, a final polish on each side at 1keV and 5.3nA can help, but it may be very hard to see what you are doing..

    How to prepare a TEM sample manually (continued)

    Note that these final thinning steps are the most important steps andno amount of text or images can adequately explain what onlyexperience is able to teach you.

    10.20