Projects per year
Abstract
We report on a floating buffer model to explain 'kink,' a hysteresis in the output characteristics of Fe-doped AlGaN/GaN HEMTs observed at low drain bias. Unintentionally doped background carbon can make the GaN buffer p-type allowing it to electrically float. We further note that reverse bias trap-assisted leakage across the junction between the 2DEG and the p-type buffer can provide a mechanism for hole injection and buffer discharging at just a few volts above the knee, explaining the 'kink' bias dependence and hysteresis. We show that HEMTs with a different background carbon have dramatically different kink behaviors consistent with the model. Positive and negative magnitude drain current transient signals with 0.9-eV activation energy are seen, corresponding to changes in the occupation of carbon acceptors located in different regions of the GaN buffer. The observation of such signals from a single trap calls into question conventional interpretations of these transients based on the bulk 1-D deep-level transient spectroscopy (DLTS) models for GaN devices with floating regions.
Original language | English |
---|---|
Article number | 8432505 |
Pages (from-to) | 3746-3753 |
Number of pages | 8 |
Journal | IEEE Transactions on Electron Devices |
Volume | 65 |
Issue number | 9 |
Early online date | 10 Aug 2018 |
DOIs | |
Publication status | Published - 1 Sept 2018 |
Research Groups and Themes
- CDTR
Keywords
- Carbon doping
- drain current transient spectroscopy
- floating buffer
- GaN
- HEMT
- iron doping
- kink effect
- traps
Fingerprint
Dive into the research topics of ''Kink' in AlGaN/GaN-HEMTs: Floating buffer model'. Together they form a unique fingerprint.Projects
- 1 Finished
-
High Performance Buffers for RF GaN Electronics
Kuball, M. H. H. (Principal Investigator)
17/11/16 → 16/05/20
Project: Research