CMOS Process steps
Modern processes often have more than twenty mask levels with more
than one hundred processing steps. These steps are classified as either frontend
or back-end processing. Front-end processing refers to the formation of
the transistors directly on the silicon. Back-end processing is the creation of
metal interconnecting wires, which are isolated by insulating materials, to
connect the transistor formations.
Some process steps are
Silicon crystal growth
Wet cleaning
Photolithography
Ion implantation
Dry etching
Wet etching
Plasma etching
Thermal treatments (rapid thermal annealing, furnace annealing, and
oxidation)
Chemical vapor deposition
Physical vapor deposition
Molecular beam epitaxy
Electrochemical deposition
Metallization
Chemical–mechanical planarization
Wafer testing
Wafer backgrinding
Wafer mounting
Die cutting