Caeleste published a white paper on "Photon counting and color X-ray imaging in standard CIS technology".
The 100x100um color X-ray pixel has quite complex functionality:
The counters are charge-based analog ones and the pixel layout is quite compact with 80% metal limited fill factor:
The 100x100um color X-ray pixel has quite complex functionality:
The counters are charge-based analog ones and the pixel layout is quite compact with 80% metal limited fill factor: