Revision as of 11:26, 19 January 2018

All samples for EBSD must be polished using the procedure outlined here or to a similar quality before EBSD. http://optics.eee.nottingham.ac.uk/wiki/AM_Sample_Preparation_for_SRAS_and_EBSD

They also need to be thoroughly cleaned using the procedure outlined here or similar. http://optics.eee.nottingham.ac.uk/wiki/How_to_clean_a_sample_prior_to_lithography

Finally, you could use the plasma cleaner (upstairs in the sample prep room of the NMRC), but the ion cleaning head does a similar job.

Contact Elisabeth Steer <pczeds@exmail.nottingham.ac.uk> if you want to use the plasma cleaner.

Contact Martin Roe <epzmjr@exmail.nottingham.ac.uk> for SEM training.

Contact Nigel Neate <epzncn@exmail.nottingham.ac.uk> for EBSD training.

Installing the sample

Check if sample is in “Specimen Exchange” position

VENT the specimen exchange chamber

Wear latex gloves. Open door, place sample in chamber, close the door

(Place the area you want to EBSD closest to the outer edge of the door/closest to you when the door is shut)

EVAC the chamber

Using the plasma cleaner

Move ion cleaning head in

Open valve on top of the argon bottle (2-3 turns) to open it, wait 5 seconds and close it

Set voltage, time and hit START

Move ion cleaning head out

SEM

Fill the reservoir with liquid nitrogen

Wear latex gloves. Move sample into chamber using the stick

Wait for chamber vacuum to go down to 10-4

Switch beam ON

Mechanical Alignment (Beam)

Check dynamic focus is off

Apature 3 (or 2) 50μm (or70) Spot size 8 Filter 3

Set working distance to 10mm

Go to about 30,000 mag

Hit ALIGN

Align using the mechanical X and Y nobs on the SEM

Alignment (Sample)

Change working distance to 20mm and Spot size 11

Hit ALIGN

Go to about 2000 mag

Align using the X and Y nobs on the control panel

Set tilt to 70deg

Switch on Dynamic Focus

Focus the centre then the top

EBSD

Move detector into 180-188 max – 195 absolute MAX

Find your region of interest and close the camera

Recheck focus and dynamic focus

Scan image

Settings

Image scan size 1024 ( or greater for a better resolution of the background IMAGE ONLY)

Dwell time 35

✔ SE

☐ BSE

✔ FSE

✔ Auto

✔ Tilt centre

Optimise pattern

Binning 4x4

Gain 15

Hit Auto exposure

90% signal strength

✔ Auto background

✔ Static background

Frame average

Check static background (300)

Optimise Solver

Settings

No of bands 6 MIN

Hough resolution 40-60

MAD as low as possible

Acquire Map

Select the area you want to map

Once area is selected (based on grain size) pick a suitable step size and time

Settings

Pick resolution you want

✔ Store Patterns

✔ Beam off after scan

✔ Acquire post-acquisition image

Removign the sample

Retract EBSD detector

Click Specimen Exchange position on the SEM window

Switch Dynamic focus off

Wear latex gloves. Once the sample has stopped moving used the stick and pull the sample out

VENT the specimen exchange chamber

Open door, remove the sample from the chamber, close the door

EVAC the chamber