Housekeeping and Cleanroom Etiquette
One of the most effective ways to keep a lab safe and increase productivity is to keep it clean. Pathways should be clear, table tops should be clean, and chemicals should be kept in the proper storage place. It is very frustrating to have to clean an instrument before you use it because someone else left it dirty. Having to search for or make new solutions of chemicals that have not been put away correctly wastes time and chemicals. Be courteous and clean up your own space. It is your responsibility to clean what you use. Before leaving the cleanroom, you should also do a quick check of all the areas you worked in to insure you do not inadvertently leave things out of place.
You may want to check for the following:
- Are there any chemicals, waste, or general garbage that has been left out?
- Are there any spills that need to be cleaned up?
- Are all the chemicals you used labeled and in the right place?
- Are all of your materials stored in your bin?
- Has all of the equipment you used been cleaned and turned off (if it is supposed to be)?
- Did you open any gas cylinders that you forgot to close?
- Is there anything else you may have turned on that you need to turn off?
Being the first one in or the last one out
If you are the last one in the cleanroom in the evening make sure you turn off the oxygen. Check the rest of the cleanroom equipment and gases to make sure nothing is still on that should be turned off. If you are the first one in the cleanroom in the morning, the oxygen will need to be turned on.
Equipment that should be left on
- PECVD - this should be returned to room temperature at night. Once the temperature is below 100, the chiller can be turned off. The vacuum for the PECVD should be turned off at night.
Leaving the lab
Clean up after yourself. Leave stations neat and ready for the next person to use. Remove personal items from general-use areas after you are done processing. Any materials you plan on taking out of the lab with you should be bagged to prevent contamination. Zip-loc bags are available in the Litho area. A vacuum sealer and sealer bags are available at the wipe down station in the gowning room.
Minimize the amount of materials stored in the lab. All personal items must be labeled with your full name, login name, and contact phone number. Storage inside the lab is limited to personal storage bins. Ample storage is available outside the lab. Contact access@snf for more information about storage.
Unlabeled chemicals are significant environmental and health hazards. When you make up a solution, remember to label it.
When labeling a solution, you should include the following:
- Name of the material contained
- Primary hazard of the material
- Person responsible for the material
- Date of filling or preparation
If your name, the substance, and a date are not present on any chemicals left out on the counters (specifically those in glassware), the chemicals will be disposed of. If any chemicals need to be left out on the counters for longer than 48 hours, the label should include the date prepared and the date the solution will be cleaned up. Be courteous and clean up you own chemicals in reasonable time frames.
Cleanroom equipment often requires long periods of usage. Be courteous to others who may want to use the same equipment. Before you begin, know what you are going to do and what you need. Proper planning of your tasks saves time, increases safety, and prevents damage to the equipment.
Common Sense and Common Courtesy
The most important parts of housekeeping and cleanroom etiquette are common sense and common courtesy. Lists should not be necessary for much of the behavior expected in the cleanroom. Obviously, there should be no horseplay in the cleanroom. If you deplete a squeeze bottle of a frequently used chemical, refill it. If the supply of a chemical is getting low, let the lab manager know so that more may be ordered. Basically, follow the "golden rule" and think about what you are doing.
Rules and Guidelines for Personal Lab Behavior
Drinking, eating and gum-chewing are not allowed in any part of the lab. Full cleanroom attire must always be worn while in the cleanroom. Be discrete in coughing, sneezing, or blowing your nose. If you can, go into the service area or gowning room. At the very least, turn away from the processing area and change your vinyl gloves before commencing processing. Minimize the amount of materials stored in the lab. All personal items must be labeled with your full name, login name, and contact phone number. Storage inside the lab is limited to personal storage bins. Ample storage is available outside the lab. Contact access@snf for more information about storage.
Acceptable Materials in the Cleanroom
Cleanroom notebooks and cleanroom paper (available in Stores.)
Wafers and tweezers, in labeled boxes.
Pens (preferably ball-point).
Materials with smooth, hard surfaces which can be cleaned with alcohol wipes.
The following materials are not considered cleanroom-compatible:
Wood pulp-based paper products, which includes regular paper, tissues, cardboard, books, and magazines.
Erasers, pencils, felt-tipped pens (other than Sharpie markers).
Anything that can easily shred or aerosolizes; i.e., anything that may serve as a source of particles.
Specific Equipment and Processes
- When using the PECVD a build-up develops around in the chamber. When you are done, vacuum out the chamber lid to get rid of the build up. Do not vacuum or let the vacuum touch any part of the actual hot plate. Doing so will melt the plastic onto the plate and create a much worse mess. Also, be sure you do not touch the hot plate with your gloves or anything else.
- SU-8 can contaminate the hydrofluoric acid etching solution. If you put a wafer with SU-8 in the HF solution, replace the etching solution.
- Hot plates are in high demand. When using a hot plate, be sure your solution will not spill and damage the hot plate. When you are done, promptly clean up the hot plate and remove you materials so that the hot plate is available for others to use.
- The Karl Suss should be turned off at night. Whenever the lamp has been turned off, you must wait at least 20 minutes before turning it on again.
- Piranha is a dangerous mixture. Use it sparingly and only when you need to. When disposing of used piranha be sure that the mixture has sat for at least 24 hours before putting it in a bottle. When putting waste piranha in a waste container, make sure no heat is produced or reactions are occurring. You still have concentrated sulfuric acid. Do not cap the waste container if gases or heat are being produced. Do not let piranha waste containers sit in the cleanroom when full.