Kink Effect, Transconductance Increase and Field Enhanced Electron-emission In Algaas/gaas Hemts

Experimental results obtained in depletion AlGaAs/GaAs HEMTs showing the presence of a remarkable increase of transconductance with frequency associated with a kink effect in the current-voltage curves is reported. Transconductance increase occurs at high frequencies with increasing drain source voltage. All these effects are ascribed to field enhanced electron emission from deep levels present in the AlGaAs layer