Specific Process Knowledge/Lithography/Aligners/Aligner: Maskless 01 processing: Difference between revisions
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In the stitching test, the design consists of ±5µm and ±1µm verniers along the X and Y axis placed in a 3 by 3 matrix covering a 60mm by 60mm area centered on the wafer. The sample is loaded, and the first layer (the linear scales) is printed. Without unloading, the second layer (the vernier scales) is printed on top of the first, and then the sample is developed. | In the stitching test, the design consists of ±5µm and ±1µm verniers along the X and Y axis placed in a 3 by 3 matrix covering a 60mm by 60mm area centered on the wafer. The sample is loaded, and the first layer (the linear scales) is printed. Without unloading, the second layer (the vernier scales) is printed on top of the first, and then the sample is developed. | ||
The results in the table below show that the errors are at or below the measurement uncertainty for the stitching tests using no flat alignment. | The results in the table below show that the errors are at or below the measurement uncertainty for the stitching tests using no flat alignment. In other words, the stage is accurate to within 100nm. | ||
<br/>When flat alignment is used, a rotation error of ~1.5ppm appears, along with a ~0.3µm misalignment and a +6ppm scaling of the Y axis. This is the level of accuracy we can expect when the rotation compensation is applied, i.e. when aligning to a previously printed layer. | <br/>When flat alignment is used, a rotation error of ~1.5ppm appears, along with a ~0.3µm misalignment and a +6ppm scaling of the Y axis. This is the level of accuracy we can expect when the rotation compensation is applied, i.e. when aligning to a previously printed layer. | ||