We report on linearity and robustness of AlN/GaN HEMTs with ultra-thin 4 nm AlN barrier for millimeter wave range applications. Static and dynamic I-V characteristics feature high peak transconductance (gmpeak) of 385 mS/mm, and the transconductance exhibits small changes with gate bias. Semi on-state step stress and 24 h stress tests have been carried out on representative AlN/GaN HEMTs on SiC substrate. No catastrophic failure was identified after semi on-state step stress at VGS = −1.5 V up to VDS = 100 V, whereas a gmpeak drop of 26% was observed in these conditions. Moreover, 24 h stress carried out at different bias voltage along a load line show good robustness of these devices up to VDS = 25 V. In addition, an abrupt gate leakage current increase was identified to be field dependent, and associated with hot spots identified by electroluminescence measurements. Even in presence of a simple SiN passivation without air bridges or field plates, these devices exhibit high power added efficiency up to 40 GHz, thus demonstrating the great potential of AlN/GaN heterostructures.

Linearity and robustness evaluation of 150-nm AlN/GaN HEMTs

Rzin M.;Meneghini M.;Rampazzo F.;De Santi C.;Medjdoub F.;Meneghesso G.;Zanoni E.
2019

Abstract

We report on linearity and robustness of AlN/GaN HEMTs with ultra-thin 4 nm AlN barrier for millimeter wave range applications. Static and dynamic I-V characteristics feature high peak transconductance (gmpeak) of 385 mS/mm, and the transconductance exhibits small changes with gate bias. Semi on-state step stress and 24 h stress tests have been carried out on representative AlN/GaN HEMTs on SiC substrate. No catastrophic failure was identified after semi on-state step stress at VGS = −1.5 V up to VDS = 100 V, whereas a gmpeak drop of 26% was observed in these conditions. Moreover, 24 h stress carried out at different bias voltage along a load line show good robustness of these devices up to VDS = 25 V. In addition, an abrupt gate leakage current increase was identified to be field dependent, and associated with hot spots identified by electroluminescence measurements. Even in presence of a simple SiN passivation without air bridges or field plates, these devices exhibit high power added efficiency up to 40 GHz, thus demonstrating the great potential of AlN/GaN heterostructures.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento 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: http://hdl.handle.net/11577/3329679
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 5
  • ???jsp.display-item.citation.isi??? 3
social impact