Abstract
An enhancement-mode AlGaN/GaN inverted-trapezoid trigate MOS high-electron-mobility transistor (HEMT), featuring double-layer oxides formed by photoenhanced chemical oxidation and plasma-enhanced atomic layer deposition (PEALD) oxide deposition, was shown to support the threshold voltage (Vth) with linear slopes of 0.36 V/nm and -0.32 V/μm2 scaled with recess depth and device area, respectively. The proposed device exhibited Vth of 1.2 V, current on/off ratio of 108, and fT/fmax of 9/36 GHz at a gate length/width of 250/360 nm. These observations can be ascribed to the combined effects of (a) an interfacial negative space charge of 3.2 μC/cm2 in the gate-recessed device that partially compensates for the spontaneous charge and (b) side-wall passivation that preserves the high-mobility channel.
Original language | English |
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Article number | 084101 |
Journal | Applied Physics Express |
Volume | 8 |
Issue number | 8 |
DOIs | |
Publication status | Published - 2015 Aug 1 |
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)