Growth of high-quality In0.28Ga0.72Sb/AlSb/GaSb/GaAs heterostructure by metalorganic chemical vapor deposition for single-channel Sb-based complementary metal–oxide–semiconductor applications

Abstract

The growth of high-quality In0.28Ga0.72Sb epilayer on an AlSb/GaSb/GaAs heterostructure by metalorganic chemical vapor deposition is demonstrated. The In0.28Ga0.72Sb epilayer has a fully relaxed surface roughness of ∼1.0 nm and a low threading dislocation density of ∼6.2 × 106 cm−2. The valence band offset (VBO) of 3.11 eV and conduction band offset (CBO) of 3.21 eV for an Al2O3/In0.28Ga0.72Sb interface extracted from X-ray photoemission spectroscopy data highlight its suitability for use in single-channel InGaSb-based complementary metal–oxide–semiconductor (CMOS) applications. The type-I straddling gap of an In0.28Ga0.72Sb/AlSb heterojunction with a VBO of 0.47 eV and CBO of 0.65 eV is also sufficient to prevent both electron and hole leakage currents in CMOS devices.