eTraining Introduction

Specimen Preparation

Leica Ultracut UCT

Histology

JEOL JSM-6400 SEM

Hitachi S-4700 FE-SEM

Hitachi FB-2000A FIB

Microanalysis

Veeco Dim 3000 AFM

Fluorescence Microscopes

Support

Films

Multiprep Polishing Procedure

Equipment is MultiPrep™ System, which includes the MultiPrep™ positioning device, the TechPrep™ polishing machine, 8" platen and dial indicator calibration kit, Allied High Tech Products Inc., and Stirrer/Hot Plate, Corning.

Procedure by Raghav Vanga.

NOTES

Do not use colloidal silica.
When performing the final polish, be aware that colloidal silica should NOT be used if you intend to do X-ray microanalysis. The silica will be embedded in cracks, pores and other features, giving rise to a silicon peak in the X-ray spectra. It is recommended that you use 1 μm diamond for the last polishing step.

Clean and dry beforing using.
Regardless of what final polish compound is used, be sure to ultrasonic clean the specimen two times, changing the solvent between cleanings. Use compressed air to remove most of the liquid, but do not immediately put the specimen into the SEM—it will need to dry in air (desiccator preferred).

Take care with the ultrasonic cleaner.
If the ultrasonic cleaner is left on overnight, the water will evaporate and the unit will be destroyed. There is a new one in the lab which has a timer which should help avoid this possibility. However, there is a "hold" setting on the timer that will leave the unit on indefinitely. Please do not use the "hold" feature.

General Precautions

Safety GlassesSAFETY GLASSES MUST BE WORN
DURING THE POLISHING PROCEDURE


Mount the Specimen to a Fixture (Base)

1. Use the 4th heat setting on the hot plate = 100ºC. VIEW
2. Heat the base and specimen at the same time to prevent heat shock.    
3. Melt some crystal bond wax on the fixture. Place the specimen on the melted wax and press it down in circular motions to be sure the wax is hot enough. VIEW
4. Remove the fixture from the hot plate and turn the hot plate off.    
5. Let the fixture and sample cool so the wax hardens and is cool to the touch.    

Sign-in the Logbook

Get the Polisher Ready

1. Set the plate on the machine and line up the holes in the plate bottom with the pins on the spindle.    
2. Turn the power on. VIEW
3. Push the coolant button and coat the plate with water. VIEW
4. Place diamond lapping film over the water. VIEW
5. Squeegee the excess to temporarily attach the film to the plate. Start with 30 µm film and work down in µm value. VIEW
6. Turn the water on and reduce the flow to a trickle over the film.    
7. Place the spindle over the film. VIEW
8. Turn on the micrometer. VIEW

Mount the Specimen to the Polisher

1. Slide the fixture upside-down onto spindle. VIEW
2. Lock it into place by pushing the red lever down. VIEW
3. Lower the specimen to the film with the red knob (coarse control) on the left of the spindle arm. VIEW
4. Set the micrometer to zero.    
5. Use the red dial (fine control) behind the spindle to raise/lower the sample until it barely touches the film. Use the micrometer to tell when that is. VIEW
6. Tare the micrometer. VIEW
7. Input 35 into the keypad > enter > play. This is the RPM. VIEW

Polish

1. Lower the specimen onto the film until the micrometer displays the number of µm that you want polished off.    
2. As the specimen is polished, the micrometer will reflect the change in thickness of the specimen by decreasing the µm reading. NOTE: As a rule, you should periodically check the progress of the specimen manually: stop the machine's rotation, lift the spindle using the red knob on the left side, raise the red lever and pull the specimen off. If it appears uniform, eg, no large scratches, you can change the lapping film to a lower µm size. Otherwise you can wait for the next step. VIEW
3. When the micrometer has reached zero, that is when you know the sample has been polished to your specifications. EXAMPLE: If you set the micrometer to 60 µm, when it reaches zero, 60 µm have been polished off.    
4. When you change films, make the display read double the microns of the last film's µm size, to make sure there are no scratches of the last film left. EXAMPLE: If the last film's µm size was 15, set the micrometer to polish off 30 µm using the 9 µm film to avoid leaving any 15 µm gouges in your sample.    

Finish

1. When the specimen is sufficiently polished, stop the machine and reset all the parameters to their original positions. VIEW
2. Dry the polisher with towels and/or compressed air. VIEW
3. Remove the plate and set it on a towel to dry.    

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