1. Overview
In the manufacturing of semiconductors, structures are created on wafers by means of lithographic methods. A light sensitive film, primarily a resist layer, is coated on top of the wafer, patterned, and transfered into the layer beneath.
Photolithography consists the following process steps:
- adding adhesives and removing moisture from the surface
- resist coating
- stabilization of the resist layer
- exposure
- development of the resist
- curing of the resist
- inspection
In some processes, as the ion implantation, the resist serves as a mask to cover certain areas which should not be doped. In this case there is no transfer of the patterned resist layer into the layer beneath.