A DELTA-DOPED GAAS/IN0.37GA0.63AS/GAAS HIGH ELECTRON-MOBILITY TRANSISTOR PREPARED BY LOW-PRESSURE METALORGANIC CHEMICAL VAPOR-DEPOSITION

A high mobility and high performance delta-doped GaAs/In0.37Ga0.63As/GaAs high electron mobility transistor (delta-HEMT) grown by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) was studied. The electron mobility of this structure at 300 and 77 K were 5500 and 33,000 cm2/v's, respectively, which were comparable with those of similar structures reported previously. With a gate geometry of 5 x 250-mu-m2, the estimated extrinsic transconductance and saturation current density at 300 K (77 K) of the proposed delta-HEMT are 56 mS/mm (78 mS/mm) and 116 mA/mm (140 mA/mm) respectively, can be achieved. The intrinsic transconductance is estimated to be 109 mS/mm (245 mS/mm) at 300 K (77 K). Furthermore. the relationships between transconductance, gate breakdown voltage, and cap-layer thickness are also investigated.