Specific Process Knowledge/Lithography/EBeamLithography/JEOLAlignment: Difference between revisions
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The optical pre-aligner is used to measure the location of the P and Q marks of the substrate after loading it to a cassette. The optical pre-alignment procedure will output a stage coordinate for both P and Q marks, a P mark shift relative to the slot center coordinate and a substrate rotation. | The optical pre-aligner is used to measure the location of the P and Q marks of the substrate after loading it to a cassette. The optical pre-alignment procedure will output a stage coordinate for both P and Q marks, a P mark shift relative to the slot center coordinate and a substrate rotation. | ||
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Prealignment using the PAMS Metrology Tool and PAMS Microscope view. Image: Thomas Pedersen. | |||
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It is usually a good idea to deal with substrate rotation first. Move the stage to the center of your substrate. Use the coordinate guide posted on the wall next to the prealigner and the coordinate read out on the table. Once you find the center of your substrate move to a horisontal feature like a cross or waveguide that will allow rotation adjustment. In the example below we have a cross (the P mark) which is obviously rotated relative to the red cross hair. | It is usually a good idea to deal with substrate rotation first. Move the stage to the center of your substrate. Use the coordinate guide posted on the wall next to the prealigner and the coordinate read out on the table. Once you find the center of your substrate move to a horisontal feature like a cross or waveguide that will allow rotation adjustment. In the example below we have a cross (the P mark) which is obviously rotated relative to the red cross hair. | ||