Slow transients observed in AlGaN HFETs: Effects of SiN/sub x/ passivation and UV illumination
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- 25 June 2003
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Electron Devices
- Vol. 50 (4) , 886-893
- https://doi.org/10.1109/ted.2003.812489
Abstract
Very slow drain current and surface potential transients have been observed in AlGaN/GaN heterostructure field effect transistors that are subjected to high bias stress. Simultaneous measurements of drain current and surface potential indicate that large change in surface potential after stress is responsible for the reduction in drain current in these devices. Measurements of surface potential profile from the gate edge toward the drain as a function of time indicate that surface potential changes occur mostly near the gate. It is proposed that the surface potential changes are caused by electrons which tunnel from the gate under high bias stress and get trapped at the surface states near the gate. Passivation of the surface with SiN/sub x/ reduces the transient magnitudes to a large extent. This correlates with a large improvement in microwave power performance in these devices after passivation. UV illumination of these devices totally eliminates the drain current and surface potential transients.Keywords
This publication has 15 references indexed in Scilit:
- Laser-induced surface potential transients observed in III-nitride heterostructuresApplied Physics Letters, 2002
- Effect of surface passivation of AlGaN/GaN heterostructure field-effect transistorElectronics Letters, 2002
- Cantilever effects on the measurement of electrostatic potentials by scanning Kelvin probe microscopyApplied Physics Letters, 2001
- Surface potential measurements on GaN and AlGaN/GaN heterostructures by scanning Kelvin probe microscopyJournal of Applied Physics, 2001
- Mechanism of radio-frequency current collapse in GaN–AlGaN field-effect transistorsApplied Physics Letters, 2001
- Very-high power density AlGaN/GaN HEMTsIEEE Transactions on Electron Devices, 2001
- The effect of surface passivation on the microwave characteristics of undoped AlGaN/GaN HEMTsIEEE Electron Device Letters, 2000
- Effect of Illumination on the Electrical Characteristics of AlGaN/GaN FETsPhysica Status Solidi (a), 1999
- AlGaN/GaN heterostructures on insulating AlGaN nucleation layersApplied Physics Letters, 1999
- Two-dimensional electron gases induced by spontaneous and piezoelectric polarization charges in N- and Ga-face AlGaN/GaN heterostructuresJournal of Applied Physics, 1999