This PhD project aims to develop and characterize a new generation of Single-Electron Bipolar Avalanche Transistors (SEBATs): silicon devices capable of detecting extremely small currents by resolving individual electrons. The work will build on FBK’s world-class custom microfabrication platform for single-photon sensors, including SPADs and SiPMs, which exploit avalanche multiplication to achieve high photon-detection efficiency and sub-20 ps timing resolution. Moving from single-photon to single-electron sensing opens a challenging and exciting frontier in semiconductor device physics, requiring dedicated device engineering, advanced electro-optical characterization, and a deep understanding of avalanche processes in silicon.

Unlike previous SEBAT demonstrations mainly based on CMOS technologies, this project will exploit the design freedom of FBK’s internal clean-room technologies to push device performance beyond the state of the art. Successful SEBATs could enable ultra-precise, Poisson-limited readout of weak current signals, with impact across THz detection, near-infrared sensing, and photoelectric readout of NV-center diamond qubits. The candidate will contribute to a highly innovative sensor technology with strong scientific and industrial potential.