Apparatus and method for repairing resist latent images

A method and an apparatus for repairing resist latent image on a wafer are disclosed. In the method, an image scanner equipped with a first and a second wafer carrier, and a primary imaging column and a secondary imaging column is utilized to conduct the processes of imaging a resist latent image on a first wafer and repairing a defect in a resist latent image on a second wafer positioned on a second wafer carrier simultaneously. The primary imaging column and the secondary imaging column may be situated in the same vacuum chamber to facilitate operation.