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Wafer Fabrication || deposition :: photolithography :: etching :: ion implantation :: annealing  
Processing || testing :: backthinning :: coating :: assembly :: final testing   

Wafer Fabrication :: photolithography

Photolithography is the process by which structures of different size and shape are created on the wafers. The wafers are first coated with photoresist, a polymer that is sensitive to ultraviolet light. The wafers are then exposed to UV light through a mask, which acts like a stencil; only letting light hit the wafers in certain places to form a pattern. Photoresist polymers can be created so that UV light either weakens or strengthens the polymer, so that when the photoresist is developed, the weaker material is washed away, leaving behind the desired pattern.
Applying Photoresist Applying the Mask Applying Developer
closeup of appling photoresist machine that applies the mask applying the photoresist
Previous Step :: deposition
Next Step :: etching

video link of wafer during photolithography
Photolithography Video
Video describing each step of the photolithographic process.

The complete video is 3:32, for slower connections the video has been broken up into 2 smaller sections
Part 1 :: Part 2

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