Surface Cleanliness



 

Sample Handling – Avoid Touching Surface

Good sample preparation is vital as surface contamination from gloves etc. can overwhelm the signals from the sample.

  • Gloves (powder free nitrile or polyethylene) and clean tweezers must be used and any glassware must be thoroughly cleaned before use. Tweezers should be cleaned regularly by sonication in isopropyl alcohol (IPA).
  • Samples can be stored or transported in clean petri dishes and well plates (polystyrene), or clean glass vials. Avoid ALL other plastic containers, including plastic sample bags. A good alternative to plastic or glass containers is new, clean aluminum foil (NOT commercial Reynolds Wrap).
  • In situ sample cleaning by Ar+ etching is available for the removal of thin oxide layers but will cause surface chemical damage and reduce available analysis time. The C60 cluster gun preserves surface chemistry and composition especially for organic and polymer surfaces but significantly reduces analysis time.
  • If the samples have been immersed in electrolytes/salt solutions then wash in distilled water and dry in air. Samples with high surface area, high vapor pressure or which have been immersed in liquids will require longer  to pump down prior to insertion into the instrument. In general, samples should be inserted into the load lock the previous evening.
  • Samples which are sensitive to oxygen or water vapor should be mounted and loaded into the vacuum transfer vessel in the glove box.

 

 

Study of As-Received Cleanliness of Brand New Optical Surfaces

Brand New 7980 HPFS Silica Witness Plates from ULC (final)

Purpose:  Establish Baseline Starting Cleanliness of Optics to be Coated

 



 

 



 

 



 

 



 

Cleaning Efficacy Questions!


Lifetime of clean surface?

Is my surface clean?

Effects of surface cleanliness?

Is your bake-out oven contaminating parts?

Is your vacuum oven contaminating parts?

Clean room cleanliness?

Do your gloves contaminate parts?

When is it clean enough?

Do plasma cleaners clean enough?

Do UV-Ozone chambers clean parts?

How fast does Silicone Oil creep in air?