INTERFEROMETRIC LITHOGRAPHY SYSTEM AND METHOD USED TO GENERATE EQUAL PATH LENGTHS OF INTERFERING BEAMS

摘要

A system and method are provided for writing patterns onto substrates. Firstand second beams are directed to converge and substantially overlap in a commonregion on a substrate. This can be done so that the first and second beams are mutuallytemporally coherent and spatially coherent in the region of overlap to form interferencefringes to define a writing image. A beam width of the first and second beams isadjusted. This can be done so that respective path lengths of the beams are matchedwhen they reach the common region to ensure the first and second beams are mutuallyspatially coherent and temporally coherent across an entire width of the commonregion. In one example, the substrate is moved with respect to the writing image,while writing patterns onto the substrate. In another example, the substrateremains stationary.