Search results

Abstract in UndeterminedThis thesis investigates the growth and application of antimonide heterostructure nanowires for low-power electronics. In the first part of the thesis, GaSb, InSb and InAsSb nanowire growth is presented, and the distinguishing features of the growth are described. It is found that the presence of Sb results in more than 50 at. % group-III concentration in the Au seed partic

Popular Abstract in English Fish are an excellent source of healthy protein and fat in the human nutrition. However, the fisheries cannot supply enough of fish to satisfy the demand of a growing world’s population. Sustainable aquaculture can help feeding the growing world. This business is growing every year, and together with it the fish farms and fish feed factories are growing. This created thAs aquaculture expands, the volume of fish feed produced and transported must also increase. Therefore a better understanding and increased control of the factors that influence the physical quality of feed pellets is required. To achieve this goal, reliable methods measuring the physical quality of feed are needed. The Holmen pellet tester (NHP 100) could be adapted for this purpose, but the spec

The optical properties of III-V semiconductor nanowires for optical devices have been investigated by photoluminescence spectroscopy, cathodoluminescence spectroscopy and cathodoluminescence imaging. The material systems that have been studied include the nitrides (InN, GaN and AlN) and ternaries, and a few common phosphides and arsenides. Due to the different optical properties of the materials,

In this thesis an efficient nanowire fabrication technique, called Aerotaxy, is investigated. Traditional nanowire fabrication techniques include the use of a substrate as a point of nanowire nucleation which limits the amount of nanowires that can be produced per unit time. In contrary, Aerotaxy offers a continuous growth process, in the gasphase, which could substantially increase the rate at wh

We have studied the interaction of light with an array of vertically oriented III-V semiconductor nanowires both theoretically and experimentally. For the theoretical studies, electromagnetic modeling has been employed. This modeling shows that with proper tuning of the nanowire diameter, the absorption per volume semiconductor material can be 20 times higher in the nanowires than in a correspondi

It is predicted that novel nanometer-sized structures incorporating nanoparticles will have a considerable impact on our lives during the coming decades. Engineered nanoparticles are already found in a number of commercially available products. However, many applications of these nanoparticles have only reached the stage of promising ideas or research demonstrations. The number of nanoparticle-bas

There has recently been a considerable attention to the possible role of semiconductor nanowires for future device applications. To make this development feasible, precise control over the growth mechanism is required. In the Vapor-Liquid-Solid growth, the most common growth mechanism, gas phase precursors decompose in presence of catalytic particles and after supersaturating the particles, solid

This thesis concerns growth and characterization of gold-particle seeded nanowires of III-V semiconductor materials (III-V NWs). The nanowires were grown using metal-organic vapour phase epitaxy (MOVPE) and characterized by various microscopy techniques. In particular cross-sectional scanning tunnelling microscopy (XSTM) and cathodoluminescence microscopy (CL) were employed to investigate heterost

Throughout this thesis, samples of various materials with applications in energy converting devices have been prepared by focused ion beam machining and investigated by transmission electron microscopy. Energy converting devices can be solar cells or light emitting diodes, which turn light into electricity or vice versa. They can also be fuel cells or electrolyzer cells, which turn chemical energy

Low-dimensional III-V semiconductor nanoscale structures grown by epitaxial processes have emerged as a new class of materials with great promise for various device applications. This thesis describes explorations into the heteroepitaxial growth of III-V semiconductor materials in combination with other III-V materials and in combination with the commonly used Si material, in both thin layer and n

This thesis explores the possibility of using advanced device geometries and heterostructure engineering to manipulate, control, and study the electrical and optical properties of semiconductor nanowires. The first part of the thesis investigates the use of different gate-all-around architectures for creating new types of gate-controlled nanowire devices, primarily intended for fundamental studies