A technique that transfers a fine pattern onto substrate by the use of light.

In photolithography, a glass plate with a desired pattern drawn on it is used as a mask. The mask is placed onto the substrate on which a thin film of photosensitive material called the photoresist has been coated, to expose part of the substrate with visible or ultraviolet rays through the mask. Since the solubility of the photoresist to the developer solution is varied by the exposure to the light, the pattern drawn on the mask is transferred to the photoresist thin film in the development process. Photolithography is indispensable to silicon process. In the semiconductor industry, the required resolutions of horizontal patterns have reached the submicrometer level, bringing light of shorter wavelengths into use.


[Related Terms]
Electron beam lithography, Photomask