Brigham Young University–Idaho

About: Brigham Young University–Idaho is a education organization based out in Rexburg, Idaho, United States. It is known for research contribution in the topics: Wire bonding & Instructional design. The organization has 277 authors who have published 357 publications receiving 7738 citations. The organization is also known as: BYU-I & Ricks College.

Tuning charge transport in solution-sheared organic semiconductors using lattice strain

Abstract: A solution-processing method known as solution shearing is used to introduce lattice strain to organic semiconductors, thus improving charge carrier mobility. Solution-processed organic semiconductors show great promise for application in cheap and flexible electronic devices, but generally suffer from greatly reduced electronic performance — most notably charge-carrier mobilities — compared with their inorganic counterparts. Borrowing a trick from the inorganic semiconductor community, Giri et al. show how the introduction of strain into an organic semiconductor, through a simple solution-processing technique, modifies the molecular packing within the material and hence its electronic performance. For one material studied, the preparation of a strained structure is shown to more than double the charge-carrier mobility. Circuits based on organic semiconductors are being actively explored for flexible, transparent and low-cost electronic applications1,2,3,4,5. But to realize such applications, the charge carrier mobilities of solution-processed organic semiconductors must be improved. For inorganic semiconductors, a general method of increasing charge carrier mobility is to introduce strain within the crystal lattice6. Here we describe a solution-processing technique for organic semiconductors in which lattice strain is used to increase charge carrier mobilities by introducing greater electron orbital overlap between the component molecules. For organic semiconductors, the spacing between cofacially stacked, conjugated backbones (the π–π stacking distance) greatly influences electron orbital overlap and therefore mobility7. Using our method to incrementally introduce lattice strain, we alter the π–π stacking distance of 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) from 3.33 A to 3.08 A. We believe that 3.08 A is the shortest π–π stacking distance that has been achieved in an organic semiconductor crystal lattice (although a π–π distance of 3.04 A has been achieved through intramolecular bonding8,9,10). The positive charge carrier (hole) mobility in TIPS-pentacene transistors increased from 0.8 cm2 V−1 s−1 for unstrained films to a high mobility of 4.6 cm2 V−1 s−1 for a strained film. Using solution processing to modify molecular packing through lattice strain should aid the development of high-performance, low-cost organic semiconducting devices.

Solution coating of large-area organic semiconductor thin films with aligned single-crystalline domains

Abstract: Solution coating of organic semiconductors offers great potential for achieving low-cost manufacturing of large-area and flexible electronics. However, the rapid coating speed needed for industrial-scale production poses challenges to the control of thin-film morphology. Here, we report an approach—termed fluid-enhanced crystal engineering (FLUENCE)—that allows for a high degree of morphological control of solution-printed thin films. We designed a micropillar-patterned printing blade to induce recirculation in the ink for enhancing crystal growth, and engineered the curvature of the ink meniscus to control crystal nucleation. Using FLUENCE, we demonstrate the fast coating and patterning of millimetre-wide, centimetre-long, highly aligned single-crystalline organic semiconductor thin films. In particular, we fabricated thin films of 6,13-bis(triisopropylsilylethynyl) pentacene having non-equilibrium single-crystalline domains and an unprecedented average and maximum mobilities of 8.1±1.2 cm2 V−1 s−1 and 11 cm2 V−1 s−1. FLUENCE of organic semiconductors with non-equilibrium single-crystalline domains may find use in the fabrication of high-performance, large-area printed electronics. Solution printing of organic semiconductors could in principle be scaled to industrial needs, yet attaining aligned single-crystals directly with this method has been challenging. By using a micropillar-patterned printing blade designed to enhance the control of crystal nucleation and growth, thin films of macroscopic, highly aligned single crystals of organic semiconductors can now be fabricated.

The Option Value of Modularity in Design An Example from Design Rules, Volume 1: The Power of Modularity

Abstract: When the design of an artifact is "modularized," the elements of the design are split up and assigned to modules according to a formal architecture or plan. Some of the modules are "hidden," meaning that design decisions in those modules do not affect decisions in other modules; some of the modules are "visible," meaning that they embody "design rules" that hidden-module designers must obey if the modules are to work together. Modular designs offer alternatives that non-modular ("interdependent") designs do not provide. Specifically, in the hidden modules, designers may replace early, inferior solutions with later, superior solutions. Such alternatives can be modeled as "real options." In Design Rules, Volume 1: The Power of Modularity (MIT Press, 2000) we sought to categorize the major options implicit in a modular design, and to explain how each type can be valued in accordance with modern finance theory. This paper provides an example of the valuation of the modular options "splitting" and "substitution." We show that the key drivers of the "net option value" of a particular module are (1) its "technical potential" (labeled s, because it operates like volatility in financial option theory); (2) the cost of mounting independent design experiments; and (3) the "visibility" of the module in question. The option value of a system of modules in turn can be approximated by adding up the net option values inherent in each module and subtracting the cost of creating the modular architecture. A positive value in this calculation justifies investment in a new modular architecture.

The Architecture of Participation: Does Code Architecture Mitigate Free Riding in the Open Source Development Model?

Abstract: This paper argues that the architecture of a codebase is a critical factor that lies at the heart of the open source development process. We define two observable properties of an architecture: (1) modularity and (2) option value. Developers can often make informed judgments about modularity and option value from early, partially implemented code releases. We show that codebases that are more modular or have more option value (1) increase developers' incentives to join and remain involved in an open source development effort and (2) decrease the amount of free riding in equilibrium. These effects occur because modularity and option value create opportunities for the exchange of valuable work among developers, opportunities that do not exist in codebases that are not modular or have no option value.

Antibacterial properties and toxicity from metallic nanomaterials.

Abstract: The era of antibiotic resistance is a cause of increasing concern as bacteria continue to develop adaptive countermeasures against current antibiotics at an alarming rate In recent years, studies have reported nanoparticles as a promising alternative to antibacterial reagents because of their exhibited antibacterial activity in several biomedical applications, including drug and gene delivery, tissue engineering, and imaging Moreover, nanomaterial research has led to reports of a possible relationship between the morphological characteristics of a nanomaterial and the magnitude of its delivered toxicity However, conventional synthesis of nanoparticles requires harsh chemicals and costly energy consumption Additionally, the exact relationship between toxicity and morphology of nanomaterials has not been well established Here, we review the recent advancements in synthesis techniques for silver, gold, copper, titanium, zinc oxide, and magnesium oxide nanomaterials and composites, with a focus on the toxicity exhibited by nanomaterials of multidimensions This article highlights the benefits of selecting each material or metal-based composite for certain applications while also addressing possible setbacks and the toxic effects of the nanomaterials on the environment