III–V Superlattices on InP/Si Metamorphic Buffer Layers for λ≈4.8 μm Quantum Cascade Lasers

Metalorganic chemical vapor deposition (MOCVD) growth of InP‐based quantum cascade laser (QCL) structures on a Si (001) substrate is demonstrated by employing a metamorphic InP buffer layer with InAs/InP quantum dots as dislocation filters. Calibration samples consist of a strain‐compensated 11.98 nm In0.365Al0.635As/14.8 nm In0.64Ga0.36As superlattice (SL) structure as well as 5‐stages of the λ ≈ 4.8 µm QCL active region, which are grown atop the metamorphic buffer and are used to assess the structural properties of the SL through high‐resolution X‐ray diffraction and high‐resolution transmission electron microscopy. Full QCL structures with 40‐stage active region are fabricated into edge‐emitting ridge‐waveguide structures and demonstrate low temperature electroluminescence with a FWHM of 48.6 meV. Monolithic integration of an InP‐based quantum cascade laser (QCL) is demonstrated on InP metamorphic buffer layers (MBL) grown on (001) Si substrate employing InAs/InP quantum dot filters. This entire structure is grown by MOCVD and characterized using HRXRD and HRTEM. A 40‐stage QCL on an InP MBL, gave an electroluminescence signal at λ≈5 μm, with a FWHM of 48.6 meV.