Abstract
We report on the use of InGaAsP strain-compensated superlattices (SC-SLs) as a technique to reduce the defect density of Indium Phosphide (InP) grown on silicon (InP-on-Si) by Metal Organic Chemical Vapor Deposition (MOCVD). Initially, a 2 μm thick gallium arsenide (GaAs) layer was grown with very high uniformity on exact oriented (001) 300 mm Si wafers; which had been patterned in 90 nm V-grooved trenches separated by silicon dioxide (SiO2) stripes and oriented along the [110] direction. Undercut at the Si/SiO2 interface was used to reduce the propagation of defects into the III–V layers. Following wafer dicing; 2.6 μm of indium phosphide (InP) was grown on such GaAs-on-Si templates. InGaAsP SC-SLs and thermal annealing were used to achieve a high-quality and smooth InP pseudo-substrate with a reduced defect density. Both the GaAs-on-Si and the subsequently grown InP layers were characterized using a variety of techniques including X-ray diffraction (XRD); atomic force microscopy (AFM); transmission electron microscopy (TEM); and electron channeling contrast imaging (ECCI); which indicate high-quality of the epitaxial films. The threading dislocation density and RMS surface roughness of the final InP layer were 5 × 108/cm2 and 1.2 nm; respectively and 7.8 × 107/cm2 and 10.8 nm for the GaAs-on-Si layer.
Highlights
The direct growth of Indium Phosphide (InP) and gallium arsenide (GaAs) on Silicon (Si) is of strong interest for the fabrication of monolithically integrated lasers in silicon photonics (SiPh) and, more generally, to realize opto-electronic integrated circuits (OEICs)
The direct heteroepitaxy of InP/GaAs on Si is extremely challenging: the large lattice mismatches between InP, GaAs, and Si (ε InP/Si ≈ 8%, εGaAs/Si ≈ 4%), their different polarities and thermal expansion coefficient cause the formation in high density of defects, including anti-phase domains (APDs), stacking faults, twins, threading, and misfit dislocations, which typically exceed
InP-on-Si has been rather limited successfully employed in GaAs-on-Si growth [18,19,20,21,22], GaN-on-sapphire [23,24], and GaN-on-Si [25,26], thisuse work, we propose the use superlattices as an additional whileIntheir in InP-on-Si has been rather limitedstrain-compensated tool to thewe defect density in InP-on-Si
Summary
The direct growth of InP and GaAs on Silicon (Si) is of strong interest for the fabrication of monolithically integrated lasers in silicon photonics (SiPh) and, more generally, to realize opto-electronic integrated circuits (OEICs). Materials 2018, 11, x FOR PEER REVIEW thermal expansion coefficient cause the formation in high density of defects, including anti-phase domains (APDs), stacking faults, twins, threading, and misfit dislocations, which typically exceed 1. The material quaternary compounds is interesting because it allows us to independently control the system does not suffer of the typical growth issues of III-nitride compounds so that all not the strain and the composition of each strained layer. The InGaAsP material system does compressive and tensile layers can grown at their optimum temperature withoutand the tensile need oflayers long suffer of the typical growth issues of be so that all the compressive waiting time for temperature ramp up and cool down, as is the case in the. InGaN/AlGaN system can be grown at their optimum temperature without the need of long waiting time for temperature [28]. up and cool down, as is the case in the InGaN/AlGaN system [28]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
