Diamond Field-Effect Transistors With V2O5-Induced Transfer Doping: Scaling to 50-nm Gate Length

• Published in: IEEE transactions on electron devices 2020-06, Vol.67 (6), p.2270-2275
• Main Authors: Crawford, Kevin G., Weil, James D., Shah, Pankaj B., Ruzmetov, Dmitry A., Neupane, Mahesh R., Kingkeo, Khamsouk, Birdwell, A. Glen, Ivanov, Tony G.
• Format: Article
• Language: English
• Subjects: 2-D hole gas (2DHG); Acceptor materials; Current measurement; Diamond; diamond metal semiconductor field-effect transistor (MESFET); Diamonds; Doping; drain-induced barrier lowering (DIBL); electronic devices; Field effect transistors; gate length; Logic gates; Metals; power; radio frequency (RF); Scaling; Semiconductor devices; Substrates; surface transfer doping; Transconductance; Transistors; Transition metal oxides; Vanadium pentoxide; V₂O
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2020.2989736

Wereport on the fabrication and measurement of hydrogen-terminated diamond field-effect transistors (FETs) incorporating V 2 O 5 as a surface acceptor material to induce transfer doping. Comparing a range of gate lengths down to 50 nm, we observe inversely scaling peak output current and transconductance. Devices exhibited a peak drain current of ~700 mA/mm and a peak transconductance of ~150 mS/mm, some of the highest reported thus far for a diamond metal semiconductor FET (MESFET). Reduced sheet resistance of the diamond surface after V 2 O 5 deposition was verified by four probe measurement. These results show great potential for improvement of diamond FET devices through scaling of critical dimensions and adoption of robust transition metal oxides such as V 2 O 5 .