TSMC patent application US20120280346 "Sensor structure for optical performance enhancement" by Jhy-Ming Hung, Jen-Cheng Liu, Dun-Nian Yaung and Chun-Chieh Chuang proposes placing FSI color filters in trenches, similar to what ST and Samsung presented some time ago. The 140a,b,c are the color filters in trenches between the metal routing 126:
TSMC Applies for Entrenched Color Filters Patent
online engineering degree/engineering degree online/online engineering courses/engineering technology online/engineering courses online/engineering technician degree online/online engineering technology/electronic engineering online