Enhancement-mode AlGaN/GaN HEMTs Fabricated by Standard Fluorine Ion Implantation

摘要

This paper presents a fabrication technology of enhancement-mode AlGaN/GaN HEMTs using standard fluorine ion implantation. An 80 nm silicon nitride layer was deposited on the AlGaN as an energy-absorbing layer that slows down the high energy (~25 keV) fluorine ions so that majority of the fluorine ions are incorporated in the AlGaN barrier. The threshold voltage was successfully shifted from -1.9 V to +0.6 V, converting depletion mode HEMTs to enhancement-mode ones. The fluorine ion distribution profile was measured by Secondary Ion Mass Spectrometry (SIMS) and is consistent with results from SRIM (The Stopping and Range of Ions in Matter) simulation.