Apparatus for wafer patterning to reduce edge exclusion zone
An apparatus includes an edge expose unit for exposing an annular area in an edge exclusion zone of a wafer to radiation having a wavelength suitable for removing a film from the wafer in the annular area and a radiation modulator coupled to the edge expose unit for modulating the radiation to pattern the film in the annular area.
1. An apparatus comprising:
an edge expose unit for exposing an annular area in an edge exclusion zone of a wafer to radiation having a wavelength suitable for removing edge films from the wafer, the edge films having stepped edges in the edge exclusion zone;
and a radiation modulator coupled to the edge expose unit for modulating the radiation to create a continuous pattern around the annular area suitable for shortening a planarization length of the wafer to the stepped edges of the edge films.
2. The apparatus of claim 1 wherein the film is a photo resist film.
3. The apparatus of claim 1 wherein the radiation modulator performs at least one of spatial modulation and temporal modulation.
4. The apparatus of claim 3 wherein the pattern comprises circles.
5. The apparatus of claim 3 wherein the pattern comprises lines.
6. The apparatus of claim 1 further comprising a table coupled to the edge expose unit for rotating the wafer.
7. The apparatus of claim 1 further comprising a table coupled to the edge expose unit for rotating the edge expose unit around the wafer.
8. The apparatus of claim 1 wherein the radiation is ultraviolet radiation.