Nanoscale Mo Ohmic Contacts to III–V Fins

A novel contact-first approach for III-V FinFETs and trigate MOSFETs is presented. In this process, the metal contact is sputtered on the as-grown semiconductor heterostructure, and the contact metal is used as a part of the fin dry-etch mask. We demonstrate this technique in Mo/n⁺-InGaAs contact structures with fin widths in the range of 50 to 300 nm. We have measured contact resistance in the range of 5 to 20Ω · μm. These results are in good agreement with the state-of-art contact resistance obtained on planar devices using similar technology. We further explore the possibility of enhancing the contacts by wrapping the metal over the fin sidewalls and found no significant improvement.