This paper describes how dc-radio-frequency (RF) dispersion manifests itself in AlGaN/GaN heterojunction field-effect transistors when the devices are driven into different RF load impedances. The localized nature of the dispersion in the I-V plane, which is confined to the "knee" region, is observed in both RF waveform and pulsed I-V measurements. The effect is fully reproduced using 2-D physical modeling. The difference in dispersive behaviors has been attributed to the geometry of a trap-induced virtual-gate region and the resulting carrier velocity saturation being overcome by punchthrough effects under high electric fields.
|Translated title of the contribution||Analysis of DC-RF Dispersion in AlGaN/GaN HFETs Using RF Waveform Engineering|
|Pages (from-to)||13 - 19|
|Number of pages||7|
|Journal||IEEE Transactions on Electron Devices|
|Publication status||Published - Jan 2009|