Schottky-Drain Technology for AlGaN/GaN High-Electron Mobility Transistors

Dept. of Electr. Eng. & Comput. Sci., Massachusetts Inst. of Technol., Cambridge, MA, USA
IEEE Electron Device Letters (Impact Factor: 2.79). 05/2010; DOI: 10.1109/LED.2010.2040704
Source: IEEE Xplore

ABSTRACT In this letter, we demonstrate 27% improvement in the buffer breakdown voltage of AlGaN/GaN high-electron mobility transistors (HEMTs) grown on Si substrate by using a new Schottky-drain contact technology. Schottky-drain AlGaN/GaN HEMTs with a total 2-??m-thick GaN buffer showed a three-terminal breakdown voltage of more than 700 V, while conventional AlGaN/GaN HEMTs of the same geometry showed a maximum breakdown voltage below 600 V. The improvement of the breakdown voltage has been associated with the planar contact morphology and lack of metal spikes in the Schottky-drain metallization.

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