Detector substrate and flat panel detector

A detector substrate, comprising a substrate base and a plurality of detector pixel units disposed on the substrate base, wherein each of the detector pixel units comprises:

• a driver circuit on the substrate base;
• a photoelectric conversion device disposed on a side, away from the substrate base, of the driver circuit, the photoelectric conversion device comprising at least two photoelectric conversion structures sequentially connected in series, a bottom electrode of a first photoelectric conversion structure in the at least two photoelectric conversion structures being electrically connected with the driver circuit, and a top electrode of an nth photoelectric conversion structure in the at least two photoelectric conversion structures being electrically connected with a bottom electrode of an (n+1)th photoelectric conversion structure in the at least two photoelectric conversion structures, with n being greater than or equal to 1;
• and
• a bias voltage line on a side of the photoelectric conversion device away from the substrate base, the bias voltage line being electrically connected to a top electrode of a last photoelectric conversion structure in the at least two photoelectric conversion structures.