Buried contact through fin-to-fin space for vertical transport field effect transistor

Abstract

Embodiments of the present invention are directed to fabrication methods and resulting structures that provide buried contacts in the fin-to-fin space of vertical transport field effect transistors (VFETs) that connect the bottom S/D of the transistors to a buried power rail. In a non-limiting embodiment of the invention, a buried power rail is encapsulated in a buried oxide layer of a first wafer. First and second semiconductor fins are formed on a second wafer. The first wafer to the second wafer and a surface of the buried power rail in a fin-to-fin space is exposed. A buried via is formed on the exposed surface of the buried power rail. The buried via electrically couples the buried power rail to a bottom source or drain region of the first semiconductor fin.