Single Crystal Cleaning

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This article describes cleaning procedures for different single crystals.

In UHV conditions:

Au(111).

For cleaning a Au(111) single crystal. Bombard with Ar+ with a current of ~2 uAmps and a voltage of 500V for about 30mins. Then anneal to ~620C for 5 mins followed by 30 mins at ~420C. Repeat the same until the sample is clean. I check that is clean by getting the herring-bone reconstruction by STM.

Pd(111).

1.Ar+ sputtering 1kV, 4uAmp, 30mins. 2.Anneal to 1000K for 5 mins. 3.Anneal between 740K and 875K while dosing O2 on the surface (4E-8Torr seems a reasonable pressure) for 30 mins moving in this Temp range during this time. 4.Flash to 1000K and let it cool down to 550K under an O2 pressure of about 4E-8Torr . Repeat this step a few times (5 might be good). 5.Check for cleanness with a technique you have available (O2 TPD, Auger, etc.). You might have to repeat steps 3 and 4 a few times until the sample is clean.

Cu(111).

Bombard with Ar+, 2uAmp, 1kV, 30mins. Anneal to 25 mV (type k thermocouple) for 30mins to flatten the bombarded surface. Check cleanness by Auger. If not completely clean,repeat cycle.

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