Cryogenic Trapping Effects in GaN-HEMTs: Influences of Fe-Doped Buffer and Field Plates
Artikel i vetenskaplig tidskrift, 2025
This article investigates trapping mechanisms in AlGaN/GaN high electron mobility transistors (HEMTs) at cryogenic temperatures (CTs) down to 4.2 K, using pulsed I–V and drain current transient spectroscopy (DCTS) measurements. The results revealed an overall increase of trapping effects at CT. In particular, a substantial increase in current collapse at low temperatures was observed and predominately ascribed to deep acceptor states stemming from the iron (Fe)-doped GaN buffer. In contrast, devices with undoped buffer presented limited signs of trapping, which were only linked to surface and access regions. The aggravation at low temperatures of trapping effects was linked to a slower detrapping dynamic at low temperatures. Furthermore, the incorporation of gate field plates (FPs) led to a substantial attenuation of trapping and reduction of current collapse by a factor of 2.6 at CT in Fe-doped devices. These latter features were ascribed to the ability of the FP to decrease the electrical field along the device, highlighting the increased impact of FP at CTs. The results suggest that an undoped buffer with optimized gate FP could help to improve the reliability of GaN devices at low temperatures.
traps
iron (Fe)
Cryogenic
GaN high electron mobility transistors (HEMTs)
field plates (FPs)
Författare
Mohamed Aniss Mebarki
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Ragnar Ferrand-Drake Del Castillo
Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik
Denis Meledin
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Erik Sundin
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Mattias Thorsell
Chalmers, Mikroteknologi och nanovetenskap, Elektronikmaterial
A. Papamichail
Linköpings universitet
Vanya Darakchieva
Lunds universitet
Linköpings universitet
Niklas Rorsman
Chalmers, Mikroteknologi och nanovetenskap, Mikrovågselektronik
François Joint
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Victor Belitsky
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Vincent Desmaris
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
IEEE Transactions on Electron Devices
0018-9383 (ISSN) 15579646 (eISSN)
Vol. 72 8 4042-4048Ämneskategorier (SSIF 2025)
Annan elektroteknik och elektronik
Den kondenserade materiens fysik
DOI
10.1109/TED.2025.3581541