Mask aligner EVG620 Deep UV

Introduction Optical lithography is a process used in microfabrication to selectively remove parts of a thin film. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical photoresist on the substrate.
The main advantage of optical lithography with respect to e-beam lithography is its speed. An exposure of a full wafer can be completed within a couple of minutes, compared to a couple of hours for e-beam lithography.
Although optical lithography is not a real competitor for e-beam lithography as far as the resolution is concerned, it can be very useful for the fabrication of structures with sizes larger than approximately 500 nm.
One of the disadvantages of optical lithography is that it requires a very flat substrate to start with. Besides that, the process is less flexible than e-beam regarding changes to your sample design