Enhanced current-voltage characteristics of Al0.25Ga0.75As/In0.25Ga0.75As/GaAs P-HEMTs using an inverted double channel structure

Abstract

An inverted double channel Al0.25Ga0.75As/In0.25Ga0.75As/GaAs pseudomorphic high electron mobility transistor (PHEMT) 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 x 10(12)cm(-2) along with a large mobility of 5010 cm(2)/Vs at 300 K, respectively. The fabricated P-HEMT device with a gate dimension of 1.8 x 200 mu m(2) 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.