Interdigit 4H-SiC Vertical Schottky Diode for Betavoltaic Applications

We demonstrated a 4H-SiC vertical Schottky diode for betavoltaic application using interdigit front metallization. A relevant increase in the betavoltaic short-circuit current with respect to a device with a continuous standard front electrode was achieved with this novel layout allowing to collect also low-energy electrons. In particular, by irradiating the device with a monochromatic electron beam (e-beam) of 17 keV, an internal gain that is 1.4 times higher than in conventional devices was obtained. An open-circuit voltage of ~1 V was obtained for an illumination e-beam current density of 10^-8 A/cm².