The Doping of Si p‐Field‐Effect Transistor Devices by Gallium Focused Ion Beam Implantation Enabling Flexible Fabrication Routes at Moderate Temperatures

A maskless approach of forming p‐doped regions in Si wafers using the Ga source of a standard focused ion beam (FIB) system and the moderate activation temperatures of 400–700 °C is demonstrated in this work. This simple and flexible route is accessible to many research labs and is successfully used to fabricate Si‐based diodes and field‐effect transistors (FETs). For the diodes, tunneling is found to be the forward current transport mechanism. The fabricated p‐FET structures show excellent switching behavior with a high I_D,ON/I_D,OFF current ratio of 5 × 10⁶.