Antimonide

About: Antimonide is a research topic. Over the lifetime, 972 publications have been published within this topic receiving 10981 citations. The topic is also known as: antimonides.

The Nature and Origin of Atomic Ordering in Group III-V Antimonide Semiconductor Alloys

Abstract: Group III-V antimonide semiconductor alloys exhibit several types of atomic ordering when grown by molecular-beam epitaxy and metal-organic vapour-phase epitaxy. This chapter describes in detail the ordered structures that are observed and discusses in depth the current understanding of the origin of the ordering. The atomic ordering is, in general, induced at the surface during growth. The type of ordering observed is shown to depend on the growth technique and the structure of the growth surface. For (001) surfaces, it is found that surface reconstruction, in particular, the formation of surface dimer bonds, plays a key role in the ordering process. Growth of layers with different surface reconstructions results in distinct types of atomic ordering. A segregation of different-sized atoms that is driven by dimer-induced subsurface stresses is believed to occur. This lowers the strain energy associated with the surface dimerisation and accommodation of the different-sized atoms at the reconstructed growth surface. Surface atomic steps play an important role in “phase-locking” consecutively ordered surface layers. It is concluded that this model is currently the one most able to explain the majority of the observed ordering behaviour in group III-V and group IV alloy semiconductor layers grown on near (001) orientation substrates.

Method for heteroepitaxial growth of antimonide semiconductor on macrolattice dismatch substrate

Abstract: The invention relates to a method for heteroepitaxial growth of an antimonide semiconductor on a macrolattice dismatch substrate and belongs to the technical field of semiconductor material preparation. The method provided by the invention comprises the following steps: before growing the antimonide semiconductor, pre-depositing an aluminum (or AlSb) thin layer on a silicon substrate by virtue of other physical deposition (such as magnetron sputtering) thin film preparation techniques; then, loading a sample in an MOCVD system for epitaxial growth; before growth, just introducing a Sb organic source; then annealing in position for antimonide of the aluminum (or AlSb) thin layer so as to form a stable AlSb buffer layer structure; and when the antimonide starts to grow, lifting the cover degree of the antimonide semiconductor by virtue of the existing AlSb buffer layer structure. In the whole growing process, the organic aluminum source is not introduced into the MOCVD system, so that aluminum pollution of equipment is avoided. The method can be used for not only enhancing the surface cover degree of the antimonide on the macrolattice dismatch substrate, but also avoiding the memory effect of the aluminum source in the equipment.

Low-pressure PVD growth SnS/InSe vertical heterojunctions with type-II band alignment for typical nanoelectronics.

Abstract: Two-dimensional (2D) polarization-sensitive detection as a new photoelectric application technology is extensively investigated. However, most devices are mainly based on individual anisotropic materials, which suffer from large dark current and relatively low anisotropic ratio, limiting the practical application in polarized imaging system. Herein, we design a van der Waals (vdWs) p-type SnS/n-type InSe vertical heterojunction with proposed type-II band alignment via low-pressure physical vapor deposition (LPPVD) and dry transfer method. The performance compared with the distinctive thickness of anisotropic SnS component was first studied. The fabricated device with a thick (80 nm) SnS nanosheet exhibits a larger rectification ratio exceeding 103. Moreover, the SnS/InSe heterostructure shows a broadband spectral photoresponse from 405 to 1100 nm with a significant photovoltaic effect. Due to efficient photogenerated carrier separation across the wide depletion region at zero bias, the device with thinner (12.4 nm) SnS exhibits trade-off photoresponse performance with a maximum responsivity of 215 mA W-1, an external quantum efficiency of 42.2%, specific detectivity of 1.05 × 1010 Jones, and response time of 8.6/4.2 ms under 635 nm illumination, respectively. In contrast, benefiting from the stronger in-plane anisotropic structure of thinner SnS component, the device delivers a large photocurrent anisotropic ratio of 4.6 under 635 nm illumination in a zigzag manner. Above all, our work provides a new design scheme for multifunctional optoelectronic applications based on thickness-dependent 2D vdWs heterostructures.

Comparison of Thermal and Atomic-Hydrogen-Assisted Oxide Desorption Methods for Regrowth of GaSb-Based Cascade Diode Lasers

Abstract: Epitaxial regrowth of antimonide-based heterostructures is required either to improve device performance parameters or to achieve new functionalities. This work compares two major methods used for surface preparation for subsequent epitaxial regrowth in the context of antimonide heterostructures. An advantage of the atomic-hydrogen-assisted oxide removal process for regrowth of GaSb-based type I quantum well cascade diode lasers is demonstrated experimentally. Wide-ridge 2.7-µm cascade diode lasers have been fabricated from heterostructures grown either in a single epitaxial run (benchmark) or in two separate epitaxial steps (regrowth test). The heterostructure used in regrowth experiment was initially grown only up to the top waveguide layer comprising 500 nm of lightly p-doped GaSb. The surface of this incomplete laser heterostructure was exposed to typical hard mask formation and removal processing treatments. Then, the surface was chemically cleaned and subjected to two different oxide desorption methods prior to regrowth of the top cladding layer. The high-temperature thermal oxide desorption and low-temperature atomic-hydrogen-based processes were tested. The devices based on laser heterostructures regrown with the utilization of the thermal oxide desorption step demonstrated nearly twofold higher laser threshold current densities and a significant reduction of slope efficiencies compared with reference lasers grown in a single growth run. The regrown lasers based on the atomic-hydrogen-assisted surface preparation method demonstrated almost no degradation of parameters compared with the benchmark lasers. Atomic force microscopy studies of the GaSb epitaxial surface subjected to thermal oxide desorption demonstrated significant degradation of the surface morphology, while the GaSb surface cleaned by atomic hydrogen showed well-resolved atomic terraces.