MOBILITY ENHANCEMENT IN DOUBLE DELTA-DOPED GAAS INXGA1-XAS GAAS PSEUDOMORPHIC STRUCTURES BY GRADING THE HETEROINTERFACES

A novel double delta-doped heterostructure employing symmetric graded InGaAs quantum wells as the active channel grown by low-pressure metal organic chemical vapor deposition (LP-MOCVD) has been successfully fab ricated. The proposed symmetrically graded InGaAs pseudomorphic struct ure manifests significantly improved electron mobility as high as 5300 (26 000) cm2/V s at 300 (77) K due to superior confinement and to the lower interface roughness scattering at GaAs/InGaAs heterointerfaces. We also carried out photoluminescence (PL) spectra and secondary-ion mass spectrometry (SIMS) profiles to confirm the quality of the propos ed structures.