Anisotropy in the context of Isotropic etching


Anisotropy in the context of Isotropic etching

Anisotropy Study page number 1 of 1

Play TriviaQuestions Online!

or

Skip to study material about Anisotropy in the context of "Isotropic etching"


⭐ Core Definition: Anisotropy

Anisotropy (/ˌænˈsɒtrəpi, ˌænɪ-/) is the structural property of non-uniformity in different directions, as opposed to isotropy. An anisotropic object or pattern has properties that differ according to direction of measurement. For example, many materials exhibit very different physical or mechanical properties when measured along different axes, e.g. absorbance, refractive index, conductivity, and tensile strength.

An example of anisotropy is light coming through a polarizer. Another is wood, which is easier to split along its grain than across it because of the directional non-uniformity of the grain (the grain is the same in one direction, not all directions).

↓ Menu
HINT:

👉 Anisotropy in the context of Isotropic etching

In semiconductor manufacturing, isotropic etching is a method commonly used to remove material from a substrate via a chemical process using an etchant substance. The etchant may be in liquid-, gas- or plasma-phase, although liquid etchants such as buffered hydrofluoric acid (BHF) for silicon dioxide etching are more often used. Unlike anisotropic etching, isotropic etching does not etch in a single direction, but rather etches in multiple directions within the substrate. Any horizontal component of the etch direction may therefore result in undercutting of patterned areas, and significant changes to device characteristics. Isotropic etching may occur unavoidably, or it may be desirable for process reasons.

↓ Explore More Topics
In this Dossier

Anisotropy in the context of Dark matter

In astronomy and cosmology, dark matter is an invisible and hypothetical form of matter that does not interact with light or other electromagnetic radiation. Dark matter is implied by gravitational effects that cannot be explained by general relativity unless more matter is present than can be observed. Such effects occur in the context of formation and evolution of galaxies, gravitational lensing, the observable universe's current structure, mass position in galactic collisions, the motion of galaxies within galaxy clusters, and cosmic microwave background anisotropies. Dark matter is thought to serve as gravitational scaffolding for cosmic structures.After the Big Bang, dark matter clumped into blobs along narrow filaments with superclusters of galaxies forming a cosmic web at scales on which entire galaxies appear like tiny particles.

View the full Wikipedia page for Dark matter
↑ Return to Menu

Anisotropy in the context of Isotropy

In physics and geometry, isotropy (from Ancient Greek ἴσος (ísos) 'equal' and τρόπος (trópos) 'turn, way') is uniformity in all orientations. Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix a- or an-, hence anisotropy. Anisotropy is also used to describe situations where properties vary systematically, dependent on direction. Isotropic radiation has the same intensity regardless of the direction of measurement, and an isotropic field exerts the same action regardless of how the test particle is oriented.

View the full Wikipedia page for Isotropy
↑ Return to Menu

Anisotropy in the context of Soil formation

Soil formation, also known as pedogenesis, is the process of soil genesis as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors.

Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current (soil geography) and past (paleopedology) geologic periods.

View the full Wikipedia page for Soil formation
↑ Return to Menu

Anisotropy in the context of Cosmic background radiation

Cosmic background radiation is electromagnetic radiation that fills all space. The origin of this radiation depends on the region of the spectrum that is observed. One component is the cosmic microwave background. This component is redshifted photons that have freely streamed from an epoch when the Universe became transparent for the first time to radiation. Its discovery and detailed observations of its properties are considered one of the major confirmations of the Big Bang. Background radiation is largely homogeneous and isotropic. A slight detectable anisotropy is present which correlates to galaxy filaments and voids. The discovery (by chance in 1965) of the cosmic background radiation suggests that the early universe was dominated by a radiation field, a field of extremely high temperature and pressure.

There is background radiation observed across all wavelength regimes, peaking in microwave, but also notable in infrared and X-ray regimes. Fluctuations in cosmic background radiation across regimes create parameters for the amount of baryonic matter in the universe. See cosmic infrared background and X-ray background. See also cosmic neutrino background and extragalactic background light.

View the full Wikipedia page for Cosmic background radiation
↑ Return to Menu

Anisotropy in the context of Surface texture

Surface finish, also known as surface texture or surface topography, is the nature of a surface as defined by the three characteristics of lay, surface roughness, and waviness. It comprises the small, local deviations of a surface from the perfectly flat ideal (a true plane).

Surface texture is one of the important factors that control friction and transfer layer formation during sliding. Considerable efforts have been made to study the influence of surface texture on friction and wear during sliding conditions. Surface textures can be isotropic or anisotropic. Sometimes, stick-slip friction phenomena can be observed during sliding, depending on surface texture.

View the full Wikipedia page for Surface texture
↑ Return to Menu

Anisotropy in the context of Void (composites)

A void or a pore is three-dimensional region that remains unfilled with polymer and fibers in a composite material. Voids are typically the result of poor manufacturing of the material and are generally deemed undesirable. Voids can affect the mechanical properties and lifespan of the composite. They degrade mainly the matrix-dominated properties such as interlaminar shear strength, longitudinal compressive strength, and transverse tensile strength. Voids can act as crack initiation sites as well as allow moisture to penetrate the composite and contribute to the anisotropy of the composite. For aerospace applications, a void content of approximately 1% is still acceptable, while for less sensitive applications, the allowance limit is 3-5%. Although a small increase in void content may not seem to cause significant issues, a 1-3% increase in void content of carbon fiber reinforced composite can reduce the mechanical properties by up to 20%

View the full Wikipedia page for Void (composites)
↑ Return to Menu

Anisotropy in the context of Submillimeter

Submillimetre astronomy or submillimeter astronomy (see spelling differences) is the branch of observational astronomy that is conducted at submillimetre wavelengths (i.e., terahertz radiation) of the electromagnetic spectrum. Astronomers place the submillimetre waveband between the far-infrared and microwave wavebands, typically taken to be between a few hundred micrometres and a millimetre. It is still common in submillimetre astronomy to quote wavelengths in 'microns', the old name for micrometre.

Submillimetre observations can be used to trace emission from gas and dust, including the CI, CO, and CII lines. Sources behind this emission include molecular clouds and dark cloud cores, which can be used to clarify the process of star formation from earliest collapse to stellar birth, by determining chemical abundances in dark clouds and the cooling mechanisms for the molecules which comprise them. Other sources include protoplanetary discs, dusty starburst galaxies in the early Universe, immediate environments surrounding AGN, and secondary anisotropies in the cosmic microwave background.

View the full Wikipedia page for Submillimeter
↑ Return to Menu

Anisotropy in the context of Cosmic Background Explorer

The Cosmic Background Explorer (COBE /ˈkbi/ KOH-bee), also referred to as Explorer 66, was a NASA satellite dedicated to cosmology, which operated from 1989 to 1993. Its goals were to investigate the cosmic microwave background radiation (CMB or CMBR) of the universe and provide measurements that would help shape the understanding of the cosmos.

COBE's measurements provided two key pieces of evidence that supported the Big Bang theory of the universe: that the CMB has a near-perfect black-body spectrum, and that it has very faint anisotropies. Two of COBE's principal investigators, George F. Smoot III and John C. Mather, received the Nobel Prize in Physics in 2006 for their work on the project. According to the Nobel Prize committee, "the COBE project can also be regarded as the starting point for cosmology as a precision science".

View the full Wikipedia page for Cosmic Background Explorer
↑ Return to Menu

Anisotropy in the context of Oryzalin

Oryzalin is a herbicide of the dinitroaniline class. It acts through the disruption (depolymerization) of microtubules, thus blocking anisotropic growth of plant cells. It can also be used to induce polyploidy in plants as an alternative to colchicine.

Oryzalin's mode of action is inhibition of microtubule assembly, so its HRAC classification is Group D (Australia), Group K1 (global) or Group 3 (numeric).

View the full Wikipedia page for Oryzalin
↑ Return to Menu

Anisotropy in the context of Cross-laminated timber

Cross-laminated timber (CLT) is a subcategory of engineered wood panel product made from gluing together at least three layers of solid-sawn lumber at angles to each other. It is similar to plywood but with distinctively thicker laminations (or lamellae). CLT was first used in a building in the 90's. C-CLT, or circular-CLT was first used in a building (The urban woods in The Netherlands) in 2024.

The grain of each layer of boards is usually rotated 90 degrees from that of adjacent layers and glued on the wide faces of each board, usually in a symmetric way so that the outer layers have the same orientation. An odd number of layers is most common, but there are configurations with even numbers as well (which are then arranged to give a symmetric configuration). Regular timber is an anisotropic material, meaning that the physical properties change depending on the direction at which the force is applied. By gluing layers of wood at right angles, the panel is able to achieve better structural rigidity in both directions.CLT is distinct from glued laminated timber (known as glulam), which is a product with all laminations orientated in the same way.

View the full Wikipedia page for Cross-laminated timber
↑ Return to Menu

Anisotropy in the context of Vulcanized fibre

Vulcanized fibre, also known as red fibre, is a laminated plastic composed of only cellulose. This material is a tough, resilient, hornlike material that is lighter than aluminium, tougher than leather, and stiffer than most thermoplastics. The newer wood-laminating grade of vulcanized fibre is used to strengthen wood laminations used in skis, skateboards, support beams and as a sub-laminate under thin wood veneers.

A product very similar to vulcanized fibre is leatheroid; however, Leatheroid is made using a different chemical process. Since 2004, the scientific community has regained interest in this material due to its renewability and excellent physical properties, giving birth to the field of all-cellulose composites. These composites are all made of a matrix consisting of dissolved or partially dissolved cellulose, and the reinforcement remains cellulose fibres. A variety of solvents other than zinc chloride has been explored, including sodium hydroxide at low temperatures and ionic liquids. Whereas the original idea was to use long reinforcing fibres (ramie, flax, viscose, etc) in order to confer the composites with anisotropic mechanical properties, the field has also explored the use of nanocellulose.

View the full Wikipedia page for Vulcanized fibre
↑ Return to Menu