DC to RF drain current collapse in GaN-based High Electron Mobility Transistors (HEMTs) has been shown to strongly limit the output power density at microwave frequencies. The surface passivation can reduce these detrimental effects [1] but recently low current dispersion has been demonstrated even on unpassivated devices [2-3]. We report on unpassivated GaN/AlGaN/GaN HEMTs grown on SiC substrate both with intentionally undoped and doped carrier layer: extremely low drain current collapse in the order of few percent even for 50ns pulses was obtained by means of turn-on gate-lag measurements. The presence of relatively shallow electron traps within the GaN cap layer could explain the observed behaviour
Titolo: | Experimental and Simulated Gate Lag Transients in Unpassivated GaN/AlGaN/GaN HEMTs |
Autori: | |
Data di pubblicazione: | 2004 |
Abstract: | DC to RF drain current collapse in GaN-based High Electron Mobility Transistors (HEMTs) has been shown to strongly limit the output power density at microwave frequencies. The surface passivation can reduce these detrimental effects [1] but recently low current dispersion has been demonstrated even on unpassivated devices [2-3]. We report on unpassivated GaN/AlGaN/GaN HEMTs grown on SiC substrate both with intentionally undoped and doped carrier layer: extremely low drain current collapse in the order of few percent even for 50ns pulses was obtained by means of turn-on gate-lag measurements. The presence of relatively shallow electron traps within the GaN cap layer could explain the observed behaviour |
Handle: | http://hdl.handle.net/11577/2440826 |
Appare nelle tipologie: | 04.01 - Contributo in atti di convegno |