Thickness measurement of substrate using color metrology

A computer program product for obtaining a measurement representative of a thickness of a layer on a substrate, the computer program product tangibly embodied in a non-transitory computer readable medium, comprising instructions for causing a processor to:

• receive a color image from a color camera,
• perform a color correction on the color image to generate an adjusted color image having increased color contrast;
• for a pixel of the adjusted color image, determine a coordinate of the pixel in a coordinate space of at least two dimensions including a first color channel and a second color channel from color data in the adjusted color image for the pixel, and
• calculate a value representative of a thickness based on the coordinate of the pixel of the adjusted color image in the coordinate space.

A method of obtaining a measurement representative of a thickness of a layer on a substrate, comprising:

• positioning a substrate for integrated circuit fabrication in view of a color camera;
• generating a color image of the substrate from the color camera;
• color correcting the color image to generate an adjusted color image having increased color contrast;
• for a pixel of the adjusted color image, determining a coordinate of the pixel in a coordinate space of at least two dimensions including a first color channel and a second color channel from color data in the adjusted color image for the pixel;
• and
• calculating a value representative of a thickness of a layer on the substrate based on the coordinate of the pixel of the adjusted color image in the coordinate space.