Semiconductor device with single electron counting capability

A semiconductor device with single electron counting capability, comprising:

• a substrate of semiconductor material, the substrate having a main surface,
• a bipolar transistor with emitter, base and collector, comprising:
• a shallow well of a first type of conductivity in a deep well of an opposite second type of conductivity in the substrate,
• a doped region of the second type of conductivity in the shallow well at the main surface, and
• a p-n junction between the doped region and the shallow well,
• a collector-to-base breakdown voltage,
• a current or voltage source electrically connected with the emitter,
• a quenching component electrically connected with the collector, the bipolar transistor being configured for operation at a reverse collector-to-base voltage above the breakdown voltage,
• a junction-forming region arranged in the deep well under the shallow well, the junction-forming region having a doping concentration for the second type of conductivity, the doping concentration of the junction-forming region being higher than a doping concentration of the deep well outside the junction-forming region, and
• a further p-n junction between the junction-forming region and the shallow well.