Abstract: A pixel array includes a semiconductor substrate, a plurality of isolation layer segments, and a plurality of photodiodes. Each of the plurality of isolation layer segments extends through the semiconductor substrate in a first direction. Each of the plurality of isolation layer segments encloses a portion of the semiconductor substrate in a plane perpendicular to the first direction. The plurality of isolation layer segments form a grid that defines a plurality of isolated sections of the semiconductor substrate. The plurality of isolated sections of the semiconductor substrate include the portions of the semiconductor substrate. Each of the photodiodes is formed in a respective one of the plurality of isolated sections of the semiconductor substrate.