The wafer/coating/carbon layer unit comprises {TAIL ~ a workpiece} useful in the practice of {HEAD ~ the invention} 
The wafer / coating / carbon layer unit comprises { TAIL ~ a workpiece } useful in the practice of { HEAD ~ the invention }
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD