Optical Lithography

 

Microlithography is the technology used to image a pattern from a photomask onto a silicon wafer coated with a light sensitive material called photoresist.

Light is passed through the photomask, exposing the photoresist on the wafer and creating the blueprint for the metal that will be deposited on it. Wafers are eventually cut, layered and packaged together, forming integrated circuits.
Electron-beam or laser beam pattern generators are an essential part of this process.

 

These tools are used to create the photomask - a glass plate called photoblank in soda lime or quartz containing the microscopic chrome pattern of an integrated circuit.

The process of making a chip begins with the design of the circuit. Circuit designers use advanced design software to generate a pattern layout - a blueprint of the chip. This information is then transferred to a photomask pattern generator, which uses an electron-beam or a laser beam to draw the pattern on photoblank covered with photoresist. This photoblank is then developed and etched with chrome, creating the photomask.