摘要 |
A method of inspecting an array having memory blocks with page breaks disposed between them. The memory array is imaged with a sensor at a magnification such that the memory block size is a whole integer pixel multiple within the sensor. This creates an array image that is divided into sections. Those sections that include at least a portion of the memory blocks are selected into a candidate image. Pixels of the image within a boundary distance of a horizontal single line of pixels are inspected to determine horizontal edges of the memory blocks to an accuracy of a single pixel. Pixels of the image within a boundary distance of a vertical single line of pixels are inspected to determine vertical edges of the memory blocks to an accuracy of a single pixel. An image of a first memory block is compared on a pixel by pixel basis to an image of a second memory block to determine differences between pixel values in the first and second memory blocks, where the images are created at the same magnification using the imaging sensor. The differences are flagged as potential memory block defects. Images of the page breaks are compared to determine differences between pixel values of the images of the page breaks, and the differences are flagged as potential page break defects.
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