Illustration of alignment. A not yet exposed layer is aligned to an already exposed layer with the help of alignment marker objects.

Most real world structures are produced in many exposure steps. Usually after each exposure step the wafer needs to be processed outside the SEM. For the following exposure, it’s crucial that all structure elements are aligned on top of the exposed layer. In smile2 this alignment step [1] is done in the align mode, described in this chapter.


[1]One Exception is full automatic alignment. This is set up in write mode