Appendices; Appendixi - Cleaning Routine - Ossila FACT1 User Manual

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Appendices

Appendix I - Cleaning Routine
The starting point for any good organic devices is a pristinely clean substrate. However, physical
cleanliness i.e. the absence of dust and particulate matter is often different to a chemically clean
surface free from residues and contaminants. To ensure that substrates are pristinely clean we
generally start by using a hot Hellmanex III solution which acts as an electronic grade detergent.
Keeping the substrates vertical during cleaning also helps to ensure that any particulate matter falls
off the substrate. When using Hellmanex III it is also important to use a hot "dump rinse" and an IPA
sonication to ensure that no residues are left behind.
In addition, we also find that for ITO based substrates it is useful to use a hot sodium hydroxide
(NaOH) sonication to provide a more hydrophillic surface and avoid the need for a plasma ash.
The below cleaning routine is generally found to provide good surface preparation although exact
timings will depend upon the power and temperature of the sonic bath. To achieve hot solutions we
generally fill the sonic bath with boiling water from a kettle which results in a bath temperature of
around 70 to 80 degrees.

5 mins sonication in hot 1% Hellmanex III solution

2x boiling water "dump rinse"

5 mins sonication in warm IPA

2x cold water dump rinse

Optional 5 mins sonication in hot 10% NaOH and 2x cold water dump rinse

Storage in cold DI water.
Once placed in DI water the substrates are stable for at least 24 hours (and probably much more).
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