LAUSR

In this letter, we have fabricated Ge-on-insulator (Ge-OI) junctionless (JL) n-MOSFETs via wafer bonding and epitaxial lift-off (ELO) techniques. We have evaluated the electrical characteristics of Ge-OI JL n-MOSFETs with different thickness of Ge channel carefully thinned by the digital etching. Furthermore, the impact of bottom-gate biasing on the Ge-OI JL n-MOSFET devices with different Ge channel thicknesses has been demonstrated. High effective electron mobility ( $\mu _{\text {eff}}$ ) of 160 cm²/ $\text {V} \cdot \text {s}$ was obtained from a Ge-OI JL n-MOSFET with an 18 nm-thick Ge channel and subthreshold slope (S.S.) of 230 mV/dec was extracted on an even thinner 10-nm-thick Ge-OI JL n-MOSFET. Also, due to the stronger coupling between the channel and bottom-gate, we demonstrated higher ${V}_{\text {th}}$ tunability and improvement of $\mu _{\text {eff}}$ by bottom-gate biasing.