Title :
Investigation of the impact of Al mole-fraction on the consequences of RF stress on AlxGa1-xN/GaN MODFETs
Author :
Valizadeh, Pouya ; Pavlidis, Dimitris
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Univ. of Michigan, Ann Arbor, MI, USA
Abstract :
Variations of the low-frequency noise (LFN), power, and dc characteristics of a variety of SiNx passivated AlGaN/GaN MODFETs with different values of Al mole-fraction, gate length, and gate drain spacing upon RF stress are investigated. It is experimentally evidenced that the variation of Al mole-fraction (x) of the barrier AlxGa1-xN layer from 0.2 to 0.4, has no considerable impact on the drain and gate low-frequency noise current characteristics. The most noticeable variation on the device characteristics upon long-term RF stressing has been on the pinch-off voltage. Although no material degradation by increasing the Al mole-fraction has been evidenced through the low-frequency noise data, it is observed that the variation of pinch-off voltage upon RF stressing becomes more important as the Al mole-fraction increases.
Keywords :
III-V semiconductors; aluminium compounds; gallium compounds; high electron mobility transistors; microwave field effect transistors; microwave power transistors; power field effect transistors; semiconductor device noise; silicon compounds; wide band gap semiconductors; MODFET; RF stress; SiNx-AlxGa1-xN-GaN; dc characteristics; gate drain spacing; gate length; low-frequency noise; mole-fraction; pinch-off voltage; Aluminum gallium nitride; Degradation; Gallium nitride; HEMTs; Low-frequency noise; MODFETs; Radio frequency; Silicon compounds; Stress; Voltage; Al mole-fraction; MODFET; RF stress; low-frequency noise (LFN);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2005.852543
