Bringing samples into the Cleanroom (346) or PolyFabLab (347)

To avoid cross contamination of tools and to keep particle levels at a minimum, we generally want to avoid bringing samples processed “outside” into the Cleanroom or PolyFabLab (PFL). If you want to bring your sample(s) in, you need to request permission from the Fabrication Support group.

Permission is granted on an individual basis and is only valid for the requested sample type and for the equipment listed in the sample approval form. That means that

Each user must request permission separately (you are welcome to use a colleague’s form).
Separate forms must be submitted for different types of sample or materials.
List all the tools you need to use with your sample.
If you later-on need to use other tools than stated in your original request form, please update the form, change the revision number, and re-submit it to us.

Please download and complete the Sample Approval Form and submit it to training@nanolab.dtu.dk for approval.

You always need to complete a Risk Assessment (AR/APV) and get approval from the Working Enviroment Coordinator, if you bring in new materials, and particles on a surface and specially if the materials are in nanoform (at least one side <100nm). Radioactive materials, Lead, Mercury, and powder of Nanoparticles are forbidden.

Sample Origin

The cleaning procedure required heavily depends on the origin of your sample and the ennvironment at the remote production site. Exceptions to the standard cleaning procedure also depend on which equipment you would like to use.

Samples from a "Cleanroom Environment"

Substrates manufactured or processed from other cleanroom environments may be taken into our cleanroom without cleaning, if following requirements are full-filled. You still must request permission to take your sample into the cleanroom or PolyFabLab.

Cleanroom at remote location with similar or higher level of cleaniness than DTU Nanolab’s cleanroom
Packed and shipped in double-sealed plastic packaging (opened only inside the cleanroom).

Samples from "Standard Laboratories and Other"

Samples originating from standard laboratories or other places as well as samples that have not been packed appropriately (double-sealed bag) must be cleaned using the standard cleaning method, exceptions may be possible (details below).

Sample Transfer between Cleanroom (346) and PolyFabLab (347)"

From the Cleanroom to PolyFabLab: Samples can be transferred without additional cleaninig steps from the cleanroom to PolyFabLab, if they are packed in double-sealed plastic bags.

From PolyFabLab to the Cleanroom: Sample must be cleaned as if originating from a non-cleanroom environment (see above). Exceptions are possible and depend on the sample origin before entering the PolyFabLab and prcoessing done inside PolyFabLab.

MVD coating: Currently MVD coating is only possible in the cleanroom. Samples may be transferrer from PFL to the Cleanroom without additional cleaning if

transfer from PolyFabLab to cleanroom in a double-sealed bag
only MVD is used.

You must fill out the Sample Approval Form and request permission for transferring samples between the Cleanroom and PolyFabLab (for both directions).

Cleaning Procedures

Commonly, samples must be cleaned using our Standard Cleaning Procedure (for either Cleanroom or PolyFabLab).

Exceptions to the standard cleaning procedure may be possible but heavily depend on your sample (material and cleanliness) and the equipment you would like to use. If your samples cannot handle the standard cleaning procedure, it must be specified in the Sample Approval form and an alternative cleaning process must be suggested by the user.

For any sample or material that cannot be cleaned by our standard cleaning process, you need to request special permission for processing your sample in the respective equipment from the responsible equipment group (thinfilm, dryetch, litho, wetchem, etc). If you are in doubt, please contact training@nanolab.dtu.dk.

Standard Cleaning Procedure for Cleanroom (346)

Triton-X soap cleaning with Ultrasound
10 min cleaning in a Piranha solution (sulfuric acid and hydrogen peroxide)

Standard Cleaning Procedure for PolyFabLab (347)

Triton-X soap cleaning with Ultrasound
Cleaning with IPA and DI water

Standard Cleaning Procedure for Cleanroom (346)

Part 1: Triton-X soap cleaning with Ultrasound

The bench in the gowning contains a sink, an ultrasonics bath and a rinse bath for rinsing samples cleaned in Triton X-100.

To clean the samples:

Find a suitable holder for your samples in the cupboard below the baths
Make sure the ultrasonics bath dump valve is closed
Fill the ultrasonics bath (the one made of metal) with DI water until your samples are completely covered
Add approx. 2 squeezes from the squeeze bottle with diluted Triton X-100 detergent from the rinse/spray bottle. Do NOT use undiluted Triton X-100
Close the bath lid to minimize noise from the ultrasonics bath
Start the ultrasound on the front panel
Leave the samples in ultrasonics for 10 min
Switch off ultrasound
Fill the rinse bath (the one made in plastic) with DI water and rinse your samples thoroughly
Remove and dry your samples
Place your samples in a clean holder (found on the shelves and cupboards in the gowning areas)
Dump the Triton X-100 solution
Rinse both tanks with DI water. Leave dump valves open so the baths drain completely

Part 2: 10 min cleaning in a Piranha solution (sulfuric acid and hydrogen peroxide)

Find more details here.

Standard Cleaning Procedure for PolyFabLab (347)

Part 1: Triton-X soap cleaning with Ultrasound

The bench in the gowning contains a sink and an ultrasonics bath for cleaning samples with Triton X-100.

To clean the samples:

Find a suitable holder for your samples in the cupboard below the baths
Fill the bath with DI water until your samples are completely covered
Add approx. 2 squeezes from the squeeze bottle with diluted Triton X-100 detergent from the rinse/spray bottle. Do NOT use undiluted Triton X-100
Close the bath lid to minimize noise from the ultrasonics bath
Start the ultrasound on the front panel
Leave the sample in ultrasonics for 10 min
Wipe your sample holder with DI water (or use a clean holder provided inide the PFL)
Switch off ultrasound
Drain the bath and rinse your sample thoroughly with DI Water (gun)
Remove and blow-dry your sample with N2 gun
Place your sample in your cleaned holder
Rinse the ultrasound bath with DI water

Do not use the solvent on the cleaning bench!

Part 2: Cleaning with IPA and DI water

Continue to clean your sample in solvent fume hood 05:

Rinse your sample with IPA (in a beaker)
Rinse your sample with DI water
Blow-dry with N2 gun
Place your sample back in your cleaned holder

Be aware that if you want to transfer your sample from the PoyFabLab to the cleanroom, you need to submit the Sample Aproval form.