Al0.85Ga0.15N/Al0.70Ga0.30N High Electron Mobility Transistors with Schottky Gates and Large On/Off Current Ratio over Temperature. (1st January 2017)

• Record Type: Journal Article
• Authors: Baca, Albert G.; Klein, Brianna A.; Allerman, Andrew A.; Armstrong, Andrew M.; Douglas, Erica A.; Stephenson, Chad A.; Fortune, Torben R.; Kaplar, Robert J.
• Is Part Of: ECS journal of solid state science and technology. Volume 6:Number 12(2017)
• Page Start: Q161
• Page End: Q165
• Publication Date: 2017-01-01
• Subjects: HEMT -- high electron mobility transistor -- Ultra-wide-bandgap; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2.0231712jss
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : AlGaN-channel high electron mobility transistors (HEMTs) are among a class of ultra wide-bandgap transistors that are promising candidates for RF and power applications. Long-channel Al x Ga1- x N HEMTs with x = 0.7 in the channel have been built and evaluated across the −50°C to +200°C temperature range. These devices achieved room temperature drain current as high as 46 mA/mm and were absent of gate leakage until the gate diode forward bias turn-on at ∼2.8 V, with a modest −2.2 V threshold voltage. A very large Ion /Ioff current ratio, of 8 × 10 9 was demonstrated. A near ideal subthreshold slope that is just 35% higher than the theoretical limit across the temperature range was characterized. The ohmic contact characteristics were rectifying from −50°C to +50°C and became nearly linear at temperatures above 100°C. An activation energy of 0.55 eV dictates the temperature dependence of off-state leakage.