Low-Frequency Noise Due to Iron Impurity Centers in GaN-Based HEMTs

• Published in: IEEE transactions on electron devices Vol. 71; no. 2; pp. 1 - 7
• Main Authors: Fleetwood, Daniel M., Li, Xun, Zhang, En Xia, Schrimpf, Ronald D., Pantelides, Sokrates T.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Activation energy; Aluminum gallium nitride; Aluminum gallium nitrides; Defects; Dehydrogenation; First principles; Gallium nitrides; GaN; HEMTs; High electron mobility transistors; high-electron-mobility transistor (HEMT); Impurities; Iron; LF noise; low-frequency (LF) noise; Low-frequency noise; MODFETs; Proton irradiation; radiation effects; reliability; Semiconductor devices; Temperature measurement; Wide band gap semiconductors
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2023.3347212

Commercial Schottky-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) exhibit a large peak in low-frequency (LF) noise magnitude at <inline-formula> <tex-math notation="LaTeX">\sim</tex-math> </inline-formula>325 K. An activation energy of 0.56 <inline-formula> <tex-math notation="LaTeX">\pm</tex-math> </inline-formula> 0.05 eV is determined for the responsible generation-recombination (G-R) center via Arrhenius analysis. Comparisons with first-principles calculations and complementary experimental studies show that this G-R center is due to substitutional iron impurities, Fe<inline-formula> <tex-math notation="LaTeX">_{\text{Ga}}</tex-math> </inline-formula>. Independent determination of the activation energy for this prominent noise peak enables recalibration of the Dutta-Horn model of LF noise for GaN-based HEMTs and a downward revision by <inline-formula> <tex-math notation="LaTeX">\sim</tex-math> </inline-formula>20% of past LF-noise estimates of effective defect energies. The resulting LF-noise-derived defect-energy distributions are consistent with deep-level-transient spectroscopy (DLTS) measurements on GaN-based diodes before and after 1.8-MeV proton irradiation. The activation of Fe<inline-formula> <tex-math notation="LaTeX">_{\text{Ga}}</tex-math> </inline-formula>-related centers via defect dehydrogenation during high-voltage stress is demonstrated via LF noise measurements on AlGaN/GaN-on-SiC HEMTs.