The physical mechanisms underlying RF currentcollapse effects in AlGaN–GaN high-electron-mobility transistors are investigated by means of measurements and numerical device simulations. This paper suggests the following conditions: 1) both surface and buffer traps can contribute to RF current collapse through a similar physical mechanism involving capture and emission of electrons tunneling from the gate; 2) surface passivation strongly mitigates RF current collapse by reducing the surface electric field and inhibiting electron injection into traps; 3) for surface-trap densities lower than 9 × 1012 cm−2, surface-potential barriers in the 1–2-eV range can coexist with surface traps having much a shallower energy and, therefore, inducing RF current-collapse effects characterized by relatively short time constants.

Mechanisms of RF current collapse in AlGaN-GaN high electron mobility transistors

DANESIN, FRANCESCA;MENEGHESSO, GAUDENZIO;ZANONI, ENRICO;
2008

Abstract

The physical mechanisms underlying RF currentcollapse effects in AlGaN–GaN high-electron-mobility transistors are investigated by means of measurements and numerical device simulations. This paper suggests the following conditions: 1) both surface and buffer traps can contribute to RF current collapse through a similar physical mechanism involving capture and emission of electrons tunneling from the gate; 2) surface passivation strongly mitigates RF current collapse by reducing the surface electric field and inhibiting electron injection into traps; 3) for surface-trap densities lower than 9 × 1012 cm−2, surface-potential barriers in the 1–2-eV range can coexist with surface traps having much a shallower energy and, therefore, inducing RF current-collapse effects characterized by relatively short time constants.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/2267513
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 95
  • ???jsp.display-item.citation.isi??? 80
social impact