Enhanced Current-Voltage Characteristics of Al_0.25Ga_0.75As/In_0.25Ga_0.75As/GaAs P-HEMTs Using an Inverted Double Channel Structure

An inverted double channel Al_0.25Ga_0.75As/In_0.25Ga_0.75As/GaAs pseudomorphic high electron mobility transistor (P-HEMT) grown by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) has been demonstrated for the first time. The inverted double channel heterostructure shows a high two-dimensional electron gas (2-DEG) concentration of 4.53×10¹² cm^-2 along with a large mobility of 5010 cm²/V·s at 300 K, respectively. The fabricated P-HEMT device with a gate dimension of 1.8×200 µm² shows a maximum drain current of as high as 820 mA/mm and a maximum extrinsic transconductance of 320 mS/mm at 300 K. Also, extrinsic transconductance is sustained over a wide range of gate voltages from -2.0 V to 1.8 V. In addition, a high two-terminal gate-drain reverse breakdown voltage of -17 V is obtained. The results obtained show a great potential of the inverted double channel P-HEMT for power applications.