Guide to Microscale Rapid Protyping
To Prepare the Slide:
1. Always use tweezers to handle clean slides.
- Turn on oven to 350 degrees.
- Place clean slide into the oven for at least 10 minutes. Longer is okay.
- Remove slide and place on aluminum plate for a minute or until room temperature.
To Spin Thin Films:
- Use pipette to deposit liquid onto pre-baked slide. Make sure you cover the entire area of the slide that you want to be able to use. For SU-8, fill the pipette so that the column of liquid is ~6cm for a 5 micron thick film.
- Set spin coater to desired speed. (See chart for SU-8 speed vs. thickness)
- Place slide on spin coater and tighten cap screw with hex key. Make sure the slide does not move when lightly jiggled.
- Cover the spin coater with soda bottle top.
- Turn on spin coater for longer than the chart says. Longer spin times tend to yield more uniform films. Always spin for more than 30 seconds.
- Wipe soda bottle top with a paper towel.
- Place the spun slide onto the first and second hotplates according to the SU-8 chart. Make sure to cover the slides with aluminum foil covers.
To Cure Resist:
- Place slide in microscope slide holder.
- Turn on both white light sources, the UV light source (blue box) and focus the microscope.
- All LabVIEW VI’s are in the folder: “…\LabView Programs”. “…\LabView Programs\Curing Programs\REU stuff \Controls4.vi” allows you to manuever the stage to a situable position. You must run the program in the “Initialize 1” and “Initialize 2” modes before using the “Operate” mode to move the stage.
- Enter the pattern you want to cure into “…\LabView Programs\Curing Programs\ REU stuff \CURE.vi”. If you want to save the numbers you entered into the array, just “Save As…” another name. The stage needs not return to the starting position.
- Run CURE.vi, or any program you have saved using the format of CURE.vi. The program will perform a pre-run. It will trace out the pattern three times and return to the starting position.
- Make sure to use the 50X objective to focus and cure.
- Cover the microscope with the black absorbing paper to protect yourself from the UV light.
- When the “Focus” dialogue box appears, note the value on the z-axis focus. As the program runs through each line segment of the pattern, note the z-axis values and enter the height change.
- When prompted, switch the top light source with the UV lamp and tighten the flexible coupling. Note the expected curing time. The actual curing time is slightly longer than the time the program gives.
- Put on UV goggles.
- Press the button to continue in the “Change Lightsource and Tighten Flexible Coupling” message.
- Press the lower blue button at the SAME TIME as pressing down foot pedal to start UV light. This will require two people.
- When the program finishes curing, a button will turn red. IMMEDIATELY turn off the UV light by pressing the tiny “reset” button on the light box.
Postbake and Development
- Put slide on the 50 degree hotplate according to the SU-8 chart (1 minute).
- Move slide to the 95 degree hotplate according to the chart.
- Using the green gloves and the blue scissor tweezers put the slide in the SU-8 developer according to the chart.
- After developing, dip the slide in acetone several times and allow to dry.
- You’re done, buddy! And if you’re Ray, you’re ugly too.