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Title: Ultrawide bandgap Al x Ga 1-x N channel heterostructure field transistors with drain currents exceeding 1.3 A/mm
We report an Ultrawide Bandgap Al0.4Ga0.6N channel Metal-Oxide-Semiconductor Heterostructure field effect transistor with drain currents exceeding 1.33 A/mm (pulse) and 1.17A/mm (DC), around 2-fold increase over reported for AlGaN HFETs. The increase was achieved by incorporating hybrid barrier layer consisting of an AlN spacer, n-doped Al0.6Ga0.4N barrier and a thin reverse graded AlxGa1-xN (x from 0.60 to 0.30) cap layer. To enhance current spreading, a "perforated" channel layout comprising of narrow channel sections separated by current blocking islands was used. A composite ALD deposited ZrO2/Al2O3 film was used as gate dielectric. A breakdown field above 2MV/cm was measured.
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Award ID(s):
1711322 1810116
Publication Date:
Journal Name:
Applied Physics Express
Sponsoring Org:
National Science Foundation
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