Method and device for determining coordinates of contact through-holes in memory device

A method of determining coordinates of contact through-holes (CTs) in a memory device, comprising:

• obtaining a bright voltage contrast (BVC) image including a plurality of CTs in the memory device;
• converting color components in the BVC image into grayscale values to obtain a grayscale BVC image;
• performing a dilation process on the grayscale BVC image to obtain a dilated grayscale BVC image;
• performing an erosion process on the grayscale BVC image to obtain an eroded grayscale BVC image;
• subtracting the eroded grayscale BVC image from the dilated grayscale BVC image to obtain a morphed grayscale BVC image;
• calculating a first threshold for the morphed grayscale BVC image and using the first threshold to perform a binarization process on the morphed grayscale BVC image to obtain a binarized BVC image containing a plurality of contours, wherein the first threshold is an Otsu threshold;
• calculating a width-over-height ratio and a perimeter of each of the plurality of contours in the binarized BVC image;
• determining whether the width-over-height ratio satisfies a width-over-height ratio condition and whether the perimeter satisfies a perimeter condition;
• and
• removing the corresponding contour from the plurality of contours in response to the width-over-height ratio unsatisfying the width-over-height ratio condition or the perimeter unsatisfying the perimeter condition;
• and
• determining coordinates of a center of each of the plurality of contours to be coordinates of each CT in the binarized BVC image.

A device of determining coordinates of contact through-holes (CTs) in a memory device, comprising:

• a display screen;
• a memory storing program instructions;
• and
• a processor configured to execute the program instructions stored in the memory to:
• obtain a bright voltage contrast (BVC) image including a plurality of CTs in the memory device;
• convert color components in the BVC image into grayscale values to obtain a grayscale BVC image;
• perform a dilation process on the grayscale BVC image to obtain a dilated grayscale BVC image;
• calculate a first threshold for the dilated grayscale BVC image and determine whether the first threshold is greater than or equal to a pre-determined value, wherein the first threshold is an Otsu threshold;
• in response to the first threshold being greater than or equal to the pre-determined value, perform a first image process on the dilated grayscale BVC image to obtain coordinates of each CT in the dilated grayscale BVC image;
• and
• in response to the first threshold being smaller than the pre-determined value, perform a second image process on the dilated grayscale BVC image to obtain the coordinates of each CT in the dilated grayscale BVC image.