Spin defects can occur anywhere on the wafer or throughout the entire wafer. This is an image of a spin macro defect that originated in the center of the semiconductor wafer. Spin macro defects in the center are usually due to air in the resist lines or a dirty nozzle tip that impedes the resist or causes sputtering at the start of the coat operation.
Some macro spin defects in the center of the semiconductor wafer can get quite large such as the example above.
The image above taken by EagleView is another good example of a spin defect originating in the center of the semiconductor wafer. EagleView allows you to measure the size of the defect and the percentage of the wafer impacted by the defect. In this case, the spin defect is less than 1% of the semiconductor wafer.