There are usually blobby patterns to the overall non-uniformity, with tiling for larger (full-frame and up) sensors where the different parts of the sensors are

There are usually blobby patterns to the overall non-uniformity, with tiling for larger (full-frame and up) sensors where the different parts of the sensors are stitched during lithography and commonly vertical lines or groups of lines for differences between the column amplifiers and ADCs (CMOS image sensors usually have one PGA and ADC for every column). You can look at this by searching for dark frames astrophotography people post.