Cleanroom Tips

Cleanroom Tips

Original Author: NTS, from notes in notebook dated April 11, 2014, and June 5, 2014.

This page has been adapted and edited to make it more readable etc

Introduction: Below is a compilation of practical tips for operating within a cleanroom environment, based on collective wisdom from experienced staff and senior graduate students. Always remember the guiding principle shared by Seth and a senior grad student: "Be careful and do it right. Reference procedures as needed."

General Tips

  1. Solvent Benches and Acid Hoods: Wipe down as necessary to maintain cleanliness.

  2. Handling Bins: Do not hold bins with one hand when passing through doors to ensure stability and safety.

  3. Appropriate Mask Usage: Always use the correct mask for specific operations.

  4. Tweezer Management: Minimize holding tweezers when not in use to avoid unintentional contact with sensitive materials.

  5. Label Verification: Double-check the labels on chemicals and beakers. Unlabeled containers are intentionally so, and proper training should guide their use.

  6. Non-rinse Policy: Do not rinse beakers used for acetone, IPA, and developer.

  7. Drying Labware: Avoid using wipes to dry off labware; use an N2 gun instead.

  8. Acid Labware Cleaning: Rinse out acid labware with DI water at least three times and spray dippers, but do not wipe down with wipes.

  9. Photoresist Storage: Photoresist (PR) has been relocated to the center of the middle shelf.

  10. Mask Placement: Ensure only a 2 mm gap between the top edge of the mask holder and the mask. A 5 mm gap is excessive.

  11. Mask Handling: Maintain the mask over surfaces as much as possible during transitions, such as moving it to or from the aligner table.

  12. Vacuum Release: Never release the vacuum unless the mask and holder are securely placed, and you are holding a corner of the mask to prevent sliding.

  13. Procedure Reference: Refer to procedures frequently, particularly for lithography, to avoid mistakes.

  14. Timer Synchronization: Start the timer concurrently with the process to ensure accuracy.

  15. Process Over Timer Noise: Focus on correctly stopping the process rather than being distracted by the timer's beeping.

  16. Task Management: Avoid multitasking excessively; handle one item at a time when using beakers and dippers.

  17. Dipper Handling: Avoid contact between dipper baskets and other dippers or beaker exteriors, except as needed in bins.

  18. Dipper Management: Always put away a dipper before taking out another.

  19. Empty Beaker Protocol: If you empty a solvent beaker, store it immediately rather than leaving it out.

  20. Sleeve Awareness: Be mindful of your sleeves when using the spinner to avoid contaminating samples.

  21. Lithography Adjustment: Adjust the MJB4 stage down by four notches before rotating the contact lever.

  22. Focus on Samples and Timing: Prioritize attention to samples and timing over the timer's noise.

  23. Priority of Samples Over Labware: Focus first on the samples and their timing before addressing labware management and the timer noise.

  24. Notebook Detailing: More detail is better when recording in the notebook.

  25. Careful Movement: Move sample holders and boxes slowly to prevent disruption or damage to the samples, especially in transit.