The invention relates to a microelectronic system, particularly for an X-ray detector, comprising a semiconductor layer (1) with an array of pixels (P) which are composed of photosensitive components (3) and associated electronic circuits (4). An insulating passivation layer (5) with recesses (5a) in its surface is disposed between the semiconductor layer (1) and a scintillator (8). A shielding metal (6) for the protection of the electronic circuits (4) from X-radiation may be disposed in the recesses (5a) of the passivation layer (5). Furthermore, the recesses may contain glue for the fixation of the scintillator (8), wherein the passivation layer (5) additionally serves as a spacer between scintillator (8) and semiconductor layer (1).