MBE STE3N: Characteristics of III-Nitrides growth a) High temperature growth manipulator providing long term growth of high quality AlN layers at growth temperature more than 1200°С (heater stage temperature more than 1350°С), with rotation. b) High temperature buffer layer AlN/AlGaN for growth of high quality GaN. c) Dislocation density in the top GaN active layer grown on c-sapphire substrate using high temperature AlN multilayer buffer (TS=1100-11500C), AlGaN/AlN superlattice (SL), and AlxGa1-xN (x=0.1-0.3) transition layers (900-9200C) was reduced down to (9-10)×108 cm-2 that is comparable with MOCVD GaN grown on sapphire and several times lower than in conventional MBE [1,2,3]. d) Improvement of structural quality resulted in substantial increase in electron mobility which reached the maximum value 600-650 сm2/V.s in a 1.5µm-thick GaN top layer slightly doped with silicon up to n=(3-5).1016 cm-3, that corresponds to a good quality MOCVD GaN. Sheet resistance mapping of the 3” HEMT structure |
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