The method includes {HEAD ~ the actual ion beam processing step} combined with {TAIL ~ the thermal and chemical conditioning} of the ion source and a special cleaning step 
combined with
The method includes { HEAD ~ the actual ion beam processing step } combined with { TAIL ~ the thermal and chemical conditioning } of the ion source and a special cleaning step
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH