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  • Temperature dependent pulsed IV and RF characterization of β -(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 hetero-structure FET with ex situ passivation
Title: Temperature dependent pulsed IV and RF characterization of β -(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 hetero-structure FET with ex situ passivation
In this work, we report a study of the temperature dependent pulsed current voltage and RF characterization of [Formula: see text]-(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 hetero-structure FETs (HFETs) before and after silicon nitride (Si 3 N 4 ) passivation. Under sub-microsecond pulsing, a moderate DC-RF dispersion (current collapse) is observed before passivation in gate lag measurements, while no current collapse is observed in the drain lag measurements. The dispersion in the gate lag is possibly attributed to interface traps in the gate–drain access region. DC-RF dispersion did not show any strong dependence on the pulse widths. Temperature dependent RF measurements up to 250 °C do not show degradation in the cutoff frequencies. After Si 3 N 4 deposition at 350 °C, a shift of the threshold voltage is observed which changed the DC characteristics. However, the current collapse is eliminated; at 200 ns pulse widths, a 50% higher current is observed compared to the DC at high drain voltages. No current collapse is observed even at higher temperatures. RF performance of the passivated devices does not show degradation. These results show that ex situ deposited Si 3 N 4 is a potential candidate for passivation of [Formula: see text]-(Al x Ga 1−x ) 2 O 3 /Ga 2 O 3 HFETs.  more » « less
Award ID(s):
2019749 1919798
PAR ID:
10343794
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
120
Issue:
17
ISSN:
0003-6951
Page Range / eLocation ID:
172102
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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