In this paper, a total of 57 micro and nano scale hybrid manufacturing processes are reviewed. These processes are categorized in terms of process timing and process type. Process timing is one of the most important aspects of manufacturing, and three different process schemes -concurrent, main/assistive (M/S) separate, and main/main (M/M) separate -are considered. The process type is categorized as either geometrically additive or subtractive, and all hybrid processes are categorized into combinations of additive, subtractive, and assistive process. Features and advantages are described for each of these classifications. Machining is found to be the most common process for both micro and nano-scale hybrid manufacturing. Of micro scale hybrid manufacturing schemes, 74.4% use assistive processes as a secondary process because the main purpose of most micro scale hybrid manufacturing is to improve the quality of the process. In nano scale manufacturing, 61.5% of hybrid manufacturing schemes employ assistive processes, since these processes typically focus on the fabrication of parts that are difficult to fabricate using a single, existing process. Based on a summary of published work, future trends in hybrid manufacturing at the micro and nano scale are suggested.

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Folded waveguide traveling-wave tubes (FW TWT) are among the most promising candidates for powerful compact amplifiers and oscillators in millimeter and submillimeter wave bands. In this paper, the nonstationary behavior of a FW TWT oscillator with delayed feedback is investigated. Starting conditions of the oscillations are derived analytically. Results of numerical simulation of single-frequency, self-modulation (multifrequency) and chaotic generation regimes are presented. Mode competition phenomena, multistability and hysteresis are discussed.

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The aim of this work was to develop a novel hybrid manufacturing method for nanoscale three-dimensional (3D) printing with multi-material capabilities. 3D structuring methods at the micro/nanoscale are major goals of various engineering fields, and much work has been carried out to improve the minimum feature size, geometrical complexity, and material selection. With the aim of nanoscale multimaterial printing, a hybrid process was reported with an integrated nanoparticle deposition system (NPDS) and focused ion beam (FIB) system; however this process has limitations in terms of surface roughness and control over the layer thickness, as well as with the process scale, and furthermore, lack of sacrificial layers.In this dissertation, a novel hybrid process is described, which combines aerodynamically focused nanoparticle (AFN) printing, micro-machining and focused ion beam (FIB) milling. AFN printing is based on NPDS, and micromachining was used for local planarization. In addition to these processes, spincoating was used to fabricate sacrificial layers. By bridging these different II micro/nanoscale processes, the resulting hybrid process can address the limitations of the individual processes.To create the hybrid process, each process was investigated to enable compatibility. With the AFN printing system, the surface morphology of a detached substrate was observed, and the bonding mechanism between the substrate and nanoparticles was investigated. A novel printing strategy was identified to reduce the scale of the process. With the micro-machining system, different tool geometries were investigated. Complex geometries inspired by conventional-scale tools were implemented on the micro-scale, and their effects were investigated. With the FIB system, material re-deposition phenomena were investigated to reduce defects that occur during ion sputtering. A novel path-generation strategy was identified and investigated for different scanning paths.Process capability is discussed using fabrication examples and functional applications. The novel hybrid process represents a significant advance in the state of the art, and enables far improved process scales or dimensional degree of freedom, without losing the advantages of broad choice of materials.3D-pinted micro bi-material cantilevers were fabricated as a thermal actuator.The mechanical and thermal properties of the structure were investigated using an in-situ measurement system, and irregular thermal phenomena were analyzed. It is expected that these in-situ measurements of the 3D printed microstructure will contribute to materials research.Various 3D structures can be fabricated using the process described here from a range of metal/ceramic inorganic materials, including polymers. In particular, it is expected that the process will contribute to the area of customized nanoscale structuring, with potential applications in medical treatments. It is also expected that this work will contribute to further improvements in manufacturing technology by combining different m...

Hybrid manufacturing technology has been advanced to overcome limitations due to traditional fabrication methods. To fabricate a micro/nano-scale structure, various manufacturing technologies such as lithography and etching were attempted. Since these manufacturing processes are limited by their materials, temperature and features, it is necessary to develop a new three-dimensional (3D) printing method. A novel nano-scale 3D printing system was developed consisting of the Nano-Particle Deposition System (NPDS) and the Focused Ion Beam (FIB) to overcome these limitations. By repeating deposition and machining processes, it was possible to fabricate micro/nano-scale 3D structures with various metals and ceramics. Since each process works in different chambers, a transfer process is required. In this research, nanoscale 3D printing system was briefly explained and an alignment algorithm for nano-scale 3D printing system was developed. Implementing the algorithm leads to an accepted error margin of 0.5% by compensating error in rotational, horizontal, and vertical axes.

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