Title :
AlGaN/GaN/GaN:C Back-Barrier HFETs With Breakdown Voltage of Over 1 kV and Low
Author :
Bahat-Treidel, Eldad ; Brunner, Frank ; Hilt, Oliver ; Cho, Eunjung ; Würfl, Joachim ; Tränkle, Günther
Author_Institution :
Ferdinand-Braun-Inst. fur Hochstfrequenztechnik, Berlin, Germany
Abstract :
A systematic study of GaN-based heterostructure field-effect transistors with an insulating carbon-doped GaN back barrier for high-voltage operation is presented. The impact of variations of carbon doping concentration, GaN channel thickness, and substrates is evaluated. Tradeoff considerations in on-state resistance versus current collapse are addressed. Suppression of the off-state subthreshold drain-leakage currents enables a breakdown voltage enhancement of over 1000 V with a low on-state resistance. Devices with a 5-μm gate-drain separation on semi-insulating SiC and a 7-μm gate-drain separation on n-SiC exhibit 938 V and 0.39 mΩ·cm2 and 942 V and 0.39 m Ω·cmcm2, respectively. A power device figure of merit of ~ 2.3 × 109 V2/Ω·cm2 was calculated for these devices.
Keywords :
III-V semiconductors; aluminium compounds; carbon; gallium compounds; high electron mobility transistors; power semiconductor devices; semiconductor device breakdown; wide band gap semiconductors; AlGaN-GaN-GaN:C; GaN; back barrier HFET; breakdown voltage enhancement; channel thickness; current collapse; drain leakage current; gate-drain separation; heterostructure field effect transistor; off-state subthreshold; on-state resistance; substrates; Carbon; Current measurement; Gallium nitride; HEMTs; MODFETs; Substrates; AlGaN/GaN heterostructure field-effect transistor (HFET); insulating GaN (i-GaN);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2010.2069566