DC AND RF PERFORMANCE OF LP-MOCVD GROWN AL0.25GA0.75AS INXGA1-XAS (X=0.15-0.28) P-HEMT WITH SI-DELTA DOPED GAAS LAYER/

Si-delta-doped Al0.25Ga0.75As/InxGa1-xAs (x = 0.15 - 0.28) P-HEMT's, p repared by LP-MOCVD, are investigated, The large conduction band disco ntinuity leads to 2-DEG density as high as 2.1 x 10(12)/cm(2) with an electron mobility of 7300 cm(2)/V . s at 300 K. The P-HEMT's with 0.7 x 60 mu m gate have a maximum extrinsic transconductance of 380 mS/mm, and a maximum current density of 300 mA/mm, The S-parameter measureme nts indicate that the current gain and power gain cutoff frequencies a re 30 and 61 GHz, respectively, The RF noise characteristics exhibit a minimum noise figure of 1.2 dB with an associated gain of 10 dB at 10 GHz. Due to the efficient doping technique, the electron mobility and transconductance obtained are among the best reported for MOCVD grown P-HEMT's with the similar structure.