ASML 5500: Choose Marks for Prealignment
How to edit your job and choose which alignment marks the system will use for optical prealignment, performed on the P-Chuck (before wafer is moved to the exposure E-Chuck).
- Edit your job with Modify Job
- Go to Layer Layout > Process Data
- Use Layer: (Prev) / (Next) to select the layer you need to change alignment marks for
- Under Prealignment Mode: Selection: Mark 1___ & Mark 2___ choose the alignment marks to align to, and use a microscope to make sure these alignment marks are (a) present on your wafer and (b) look ok with no defects.
- The wafer schematic shows which alignment marks you are choosing.
- The alignment marks, defined on a previous layer (usually combined with the first litho), are programmed/named in: <to be added: where in the program the AlMks are defined>
- Your "Fine" alignment marks will probably also fail if they're set to use the same marks! Fix this by editing your Wafer Layout > Alignment Strategy, and select different alignment marks or set some "backup" marks. Make sure your Layer Layout > Strategy Selection is using this new/updated strategy.