Exposure module with cleaning scrubber

A method comprising:

• cleaning a wafer table by using a cleaning scrubber having a plurality of tapered microstructures protruding from a surface of the cleaning scrubber, wherein the surface of the cleaning scrubber comprises an inner annular region and an outer annular region around the inner annular region, wherein first ones of the plurality of tapered microstructures within the outer annular region have a height different from a height of second ones of the plurality of tapered microstructure within the inner annular region, wherein the plurality of tapered microstructures have a Vickers-hardness greater than a Vickers-hardness of titanium nitride (TiN);
• after cleaning the wafer table, placing a semiconductor wafer onto the wafer table;
• and
• after placing the semiconductor wafer onto the wafer table, performing a semiconductor manufacturing process on the semiconductor wafer.

A method comprising:

• performing a photolithography process on a first wafer held on a wafer table;
• unloading the first wafer from the wafer table;
• after unloading the first wafer, cleaning the wafer table by using a cleaning scrubber, wherein the cleaning scrubber comprises a major surface and a plurality of microstructures extending from the major surface, wherein the major surface of the cleaning scrubber comprises an inner annular region and an outer annular region around the inner annular region, wherein first ones of the plurality of microstructures within the outer annular region have a height different from a height of second ones of the plurality of microstructure within the inner annular region;
• after cleaning the wafer table, loading a second wafer onto the wafer table;
• and
• performing another photolithography process on the second wafer.