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Quantum dot (QD) laser as a light source for silicon optical integration has attracted great research attention because of the strategic vision of optical interconnection. In this paper, the communication band InAs QD ridge waveguide lasers were fabricated on GaAs-on-insulator (GaAsOI) substrate by combining ion-slicing technique and molecular beam epitaxy (MBE) growth. On the foundation of optimizing surface treatment processes, the InAs/In0.13Ga0.87As/GaAs dot-in-well (DWELL) lasers monolithically grown on a GaAsOI substrate were realized under pulsed operation at 20 °C. The static device measurements reveal comparable performance in terms of threshold current density, slope efficiency and output power between the QD lasers on GaAsOI and GaAs substrates. This work shows great potential to fabricate highly integrated light source on Si for photonic integrated circuits.

AlSbBi thin films with a Bi content up to 15% have been successfully grown by molecular beam epitaxy for the first time. The effect of growth temperature, Sb flux and Bi flux on Bi incorporation are systematically studied. The incorporation of small size Al atoms is proven to be beneficial to improve the stability of AlSbBi with no change of Bi content in the growth temperature range of 360-420 degrees C. The AlBi lattice constant is determined to be about 6.37 angstrom by the combination of Rutherford backscattering spectroscopy and high resolution X-ray diffraction. The new AlBi vibration modes located at 286 cm(-1) and 295 cm(-1) are observed and attributed to AlBi TO and LO mode, respectively, in agreement with theoretical simulations. (C) 2019 Elsevier B.V. All rights reserved.

In this paper, InGaAs p-i-n photodetectors (PDs) on an InP/SiO2/Si (InPOI) substrate fabricated by ion-slicing technology are demonstrated and compared with the identical device on a commercial InP substrate. The quality of epitaxial layers on the InPOI substrate is similar to that on the InP substrate. The photo responsivities of both devices measured at 1.55 µm are comparable, which are about 0.808–0.828 A W−1. Although the dark current of PD on the InPOI substrate is twice as high as that of PD on the InP substrate at 300 K, the peak detectivities of both PDs are comparable. In general, the overall performance of the InPOI-based PD is comparable to the InP-based PD, demonstrating that the ion-slicing technology is a promising route to enable the high-quality Si-based InP platform for the full photonic integration on a Si substrate.

Dilute bismide and nitride provide flexible bandgap and strain engineering, owing to their unique physical properties, and are attractive for mid-IR (2–12 μm) optoelectronic device applications. In this chapter, we review progresses of theoretical simulations, epitaxial growth, material characterizations, and devices of dilute bismides including GaSbBi, AlSbBi, InAsBi, InAsSbBi, InGaAsBi, and InSbBi, as well as dilute nitrides including InNAs, GaNSb, InNSb, GaInNAs, and InNAsSb. The overview mainly focuses on growth optimization, optical characterizations, and theoretical calculations ending with outlook remarks about advantages and main challenges of both exotic materials.

In this invited talk, we will present some recent progresses on epitaxial growth of III-V-Bi alloys and light emitting devices. Aluminum containing bismides including AlAsBi and AlSbBi have been epitaxially grown for the first time and their physical properties will be reported. New designs of using delta-doping in quantum wells are investigated to effectively extend light emission wavelength. Finally, GaAs based light emitting diode will be presented.

GaSb1-xBix thin film was grown on a 2 inch GaSb substrate by molecular beam epitaxy (MBE) without substrate rotation. Bi composition is found to vary from 2.76% to 3.98% across the wafer. The distribution of Bi content is mainly determined by spatial non-uniformity of Sb/Ga flux ratio, while Bi flux has slightly influence. Ostwald ripening process is confirmed to be reason for bigger Bi droplets via Bi surface diffusion. With the increase of Sb/Ga flux ratio, Ostwald ripening process is suppressed. At high Bi flux, excess Ga atoms accumulate on surface and form droplets.

A comparative study of selective dry and wet etching methods for germanium-tin (Ge1-xSnx) alloys (3.5% < x < 7.7%) and germanium (Ge) is carried out. Both etching methods are optimized from the perspectives of selectivity and morphology, and then compared. A special behavior of the selective dry etching process is discovered and explained, whereby the selectivity has a dramatic increase to as high as 336 when the Sn concentration is above 6%. Different morphologies of suspended microstructures fabricated by different etching methods are investigated. Comparative study shows that the selective dry etching is a better choice for high Sn concentration GeSn (above 7%) against Ge to have better morphology, selectivity and verticality. While for low Sn concentration GeSn (below 6%), wet etching is a better way to fabricate a suspended GeSn microstructure on Ge. This work provides a comparative understanding of both methods of selective etching for GeSn. This comparative understanding is expected to be applied in the processing of next generation electronic and photonic devices.