Page "Semiconductor device fabrication" Paragraph 14

* Patterning covers the series of processes that shape or alter the existing shape of the deposited materials and is generally referred to as lithography.

For example, in conventional lithography, the wafer is coated with a chemical called a photoresist.

The photoresist is exposed by a stepper, a machine that focuses, aligns, and moves the mask, exposing select portions of the wafer to short wavelength light.

The exposed regions are washed away by a developer solution.

After etching or other processing, the remaining photoresist is removed by plasma ashing.