Submicron alignment accuracy of frontside to backside lithography for MEMS applications

In this paper we present the results of front-to-back lithography with an alignment accuracy of less than 1 µm. These results were obtained by a combination of 1:1 and 5:1 lithography and an overlay correction by post-processing (rework) the original lithography process. The alignment error was measured using box-in-box structures with an automatic infrared measuring device.