Hi, my name is Colin and I work here in the Lithography area, or Litho for short. The Litho area is like one big photography laboratory where we expose and develop a photosensitive material.
We transfer our master-patterns onto the wafer surface.
To transfer the master-pattern, we use 3 steps; We coat the wafer with a chemical called photoresist, we pass ultraviolet light through our master-pattern or mask, onto the silicon surface. The mask will allow some of the light through to the wafer surface and block it from other areas. The surface is now washed with a developer which will remove the photoresist from all those areas exposed to the light and leave it where the mask cast a shadow. By removing the exposed photoresist we have now transferred a copy of the master-pattern to the wafer surface.
Now we send the wafers to Etch where the pattern will be etched onto the silicon to create a permanent pattern.
