Mobility enhancement in double δ-doped GaAs/In<i>x</i>Ga1−<i>x</i>As/GaAs pseudomorphic structures by grading the heterointerfaces

Abstract

A novel double δ-doped heterostructure employing symmetric graded InGaAs quantum wells as the active channel grown by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) has been successfully fabricated. The proposed symmetrically graded InGaAs pseudomorphic structure 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 proposed structures.