A Run-Time Reconfigurable Ge Field-Effect Transistor With Symmetric On-States
Andreas Fuchsberger, Lukas Wind, Daniele Nazzari, Larissa Kühberger, Daniel Popp, Johannes Aberl, Enrique Prado Navarrete, Moritz Brehm, Lilian Vogl, Peter Schweizer, Sebastian Lellig, Xavier Maeder, Masiar Sistani, W. Weber
Abstract
Here, we present a Ge based reconfigurable transistor, capable of dynamic run-time switching between n-and p-type operation with enhanced performance compared to state-of-the-art Si devices. Thereto, we have monolithically integrated an ultra-thin epitaxial and defect-free Ge layer on a Si on insulator platform. To evade the commonly observed process variability of Ni-germanides, Al-Si-Ge multi-heterojunction contacts have been employed, providing process stability and the required equal injection capabilities for electrons and holes. Integration into a three top-gate transistor enables effective polarity control and efficient leakage current suppression to limit static power dissipation. Exploiting the advantages of multi-gate transistors, combinational wired-AND gates are shown to be capable of extending a single transistor to a logic gate. Notably, the obtained Al-Si-Ge multi-heterojunction reconfigurable transistors constitute the first CMOS compatible platform to combine efficient polarity control enabling the envisioned performance enhancements of Ge based reconfigurable transistors.