Abstract
AlGaAs/InGaAs/GaAs pseudomorphic structures have been grown by atmosheric pressure-MOCVD . The Al incorporation efficiency is constant but slightly exceeds the Ga incorporation during the growth of AlGaAs layers at $650^{\circ}C$ . Meanwhile , the In incorporation efficiency is constant but slightly less than the Ga incorporation in InGAAs layers. InGaAs/GaAs QWs were grown and their optical properties were characterized . $\delta$-doped Al0.24Ga0.76As/In0.16 Ga0.84As p-HEMT structures were successfully grown by MOCVD and their transport properties were characterized by Hall effect and SdH measurements. SdH Measurements at 3.7K show clear magnetoresistance oscillations and plateaus in the quantum Hall effect confirming the existence of a two-dimensional electron gas(2DEG) and a parallel conduction through the GaAs buffer layer. The fabricated $1.5\mu\textrm{m}$gatelength p-HEMTs having p-type GaAs in the buffer layer show a high transconductance of 200 mS/mm and a good pinch-off characteristics.