This paper discusses the driving forces behind the continued strength of crystalline silicon technology. The history of silicon technology development is reviewed, and projections made as where to silicon technology is likely to go in the following 10 years. Next the barriers that have inhibited the emergence of competing technologies are discussed, along with the steps that need to be taken to surmount those barriers. Copyright © 2006 John Wiley & Sons, Ltd.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/pip.709

A vision for crystalline silicon photovoltaics

A freestanding GaN single crystal substrate is made by the steps of preparing a (111) GaAs single crystal substrate, forming a mask having periodically arranged windows on the (111) GaAs substrate, making thin GaN buffer layers on the GaAs substrate in the windows of the mask, growing a GaN epitaxial layer on the buffer layers and the mask by an HVPE or an MOC, eliminating the GaAs substrate and the mask away and obtaining a freestanding GaN single crystal substrate. The GaN single crystal has a diameter larger than 20 mm and a thickness more than 0.07 mm, being freestanding and substantially distortion-free.

GaN single crystal substrate and method of producing same

A low dislocation density GaN single crystal substrate is made by forming a seed mask having parallel stripes regularly and periodically aligning on an undersubstrate, growing a GaN crystal on a facet-growth-condition, forming repetitions of parallel facet hills and facet valleys rooted upon the mask stripes, maintaining the facet hills and facet valleys, producing voluminous defect accumulating regions (H) accompanying the valleys, yielding low dislocation single crystal regions (Z) following the facets, making C-plane growth regions (Y) following flat tops between the facets, gathering dislocations on the facets into the valleys by the action of the growing facets, reducing dislocations in the low dislocation single crystal regions (Z) and the C-plane growth regions (Y), and accumulating the dislocations in cores (S) or interfaces (K) of the voluminous defect accumulating regions (H).

Method of growing single crystal GaN, method of making single crystal GaN substrate and single crystal GaN substrate

Due to a variety of outstanding properties, such as large surface area, high length-to-diameter ratio, flexible surface functionality, tunable surface morphologies and superior mechanical performance, electrospun ultrathin fibers are suitable for flexible and stretchable devices, which have aroused much attention nowadays. In this review, we aim to summarize recent developments in the fabrication of flexible/stretchable electronic devices via electrospinning, including strain and pressure sensors, supercapacitors, organic field-effect transistors, and transparent electrodes, which are the key components of flexible/stretchable devices. Moreover, in order to further improve the performance of these devices, some challenges facing electrospun fibers (e.g. production on large scale, precise deposition and flexibility improvement of electrospun inorganic fibers) and subsequent integration for flexible/stretchable electronic devices have also been discussed.

Recent advances in flexible and stretchable electronic devices via electrospinning

A method utilizes sputter transport techniques to produce arrays or layers of self-forming, self-oriented columnar structures characterized as discrete, single-crystal Group III nitride posts or columns on various substrates. The columnar structure is formed in a single growth step, and therefore does not require processing steps for depositing, patterning, and etching growth masks. A Group III metal source vapor is produced by sputtering a target, for combination with nitrogen supplied from a nitrogen-containing source gas. The III/V ratio is adjusted or controlled to create a Group III metal-rich environment within the reaction chamber conducive to preferential column growth. The reactant vapor species are deposited on the growth surface to produce single crystal MIIIN columns thereon. The columns can be employed as a strainrelieving platform for the growth of continous, low defect-density, bulk materials. Additionally, the growth conditions can be readjusted to effect columnar epitaxial overgrowth, wherein coalescence of the Group III nitride Material occurs at the tops of the columns, thereby forming a substantially continuous layer upon which additional layers can be deposited. The intervening presence of the column structure mitigates thermal mismatch stress between substrates, films, or other layers above and below the columns. A high deposition rate sputter method utilizing a non-thermionic electron/plasma injector asssembly is provided to carrying out one or more of the growth steps.

Method and apparatus for producing miiin columns and miiin materials grown thereon

We investigate the microstructure of thin silicon films produced at temperatures below 450 °C by ion-assisted deposition. Our transmission electron microscopy investigations show that in this temperature regime epitaxial growth breaks down at a critical film thickness beyond which the growth changes to polycrystalline or amorphous. The critical thickness increases with an increase in temperature. We use this effect that is well known from molecular beam epitaxy to analyze and quantify growth on silicon substrates with different surface normal orientations at various temperatures. Our results indicate that epitaxy works by far the best for the 〈001〉 surface normal orientation. The critical epitaxial thickness hepi decreases in the sequence hepi(001)≫hepi(113)>hepi(011)>hepi(111). The respective activation energies of 0.6, 2.1, 1.2, and 1.4 eV are evaluated from the temperature dependence.

Single to polycrystalline transition in silicon growth by ion-assisted deposition at low temperatures

Real Estate Asset Management

Designing, operating and maintaining industrial plants require extensive and complex engineering processes An integrated engineering process considering all different aspects, data and workflow of plant automation design as well as interoperability to other systems is the key to more efficiency and lower costs of engineering tasks in the plant life cycle There exists no comprehensive and satisfying solution to this problem today However, an agent-oriented view can lead to fundamentally new and promising approaches to an integrated plant engineering process The goal of this paper is to clearly identify the specific goals and challenges in engineering industrial plants and to show that agents are a beneficial approach to meet them To this end, an agent-oriented solution for integrated engineering of automation systems is presented, applying the advantages of agent concepts while considering the constraints of existing automation structures

Applying Agents for Engineering of Industrial Automation Systems

The present invention relates to a process for the application of an epitactic GaN layer to a substrate by pyrolysis of precursor compounds.

Thomas Wagner

Papers

Single to polycrystalline transition in silicon growth by ion-assisted deposition at low temperatures

Real Estate Asset Management

Applying Agents for Engineering of Industrial Automation Systems

Production of epitactic GaN layers on substrates

High-quality and low-temperature epitaxial Si films deposited at very high deposition rate