High-quality InGaAs films bonded on Si substrate with a thin polycrystalline Si intermediate layer.

[Display omitted] • A polycrystalline Si layer is introduced to eradicate the influence of lattice misfit. • Ar Plasma treatment highly enhanced the bonding strength of InGaAs/Si bonded pair at low temperatures. • A defect-rich region near the epitaxial interface of InGaAs and InP is revealed by depth-dependent and power-dependent photoluminescence (PL) measurements. • A high-quality Si-based InGaAs film is obtained by heterogeneous bonding and wet etching techniques. We report the fabrication of high-quality InGaAs films on Si by wafer bonding at low temperatures (300 ℃). A thin polycrystalline Si (poly-Si) interlayer is introduced between InGaAs and Si to block the lattice mismatch and absorb the bubble by-products produced at the bonded interface using its disordered crystal orientation and gain boundaries. To achieve a high bonding strength, argon plasma treatment was employed on InGaAs and poly-Si surfaces before the pre-bonding process. By using post-wet etching, a defect-rich region near the surface of exfoliated InGaAs film that was initially caused by the thermal mismatch between InGaAs and InP during epitaxy growth can be removed. As a result, a Si-based InGaAs film with a 1.05 MPa bonding strength and bubble-free bonding interface was produced. The defective region is 1.2 μm-thick. After etching the defective area, a high-quality, 1.8 μm-thick Si-based InGaAs film was obtained with an XRD FWHM of 94 arcsec. The results reveal that this method is prospective for the fabrication of high-quality III-V materials on Si, proving that a prospective approach for the fabrication of low-noise InGaAs/Si PIN photodiodes and InGaAs/Si avalanche photodiodes with ultralow dark currents. [ABSTRACT FROM AUTHOR]