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Taiwan Semiconductor Manufacturing Company Limited ( TSMC; also called Taiwan Semiconductor) [4] [5] is a Taiwanese multinational semiconductor contract manufacturing and design company. It is the world's second most valuable semiconductor company, [6] the world's largest dedicated independent ("pure-play") semiconductor foundry, [7] and its ...
- 73,090 (2022)
- US$73.67 billion (2022)
Taiwan,[II][k] officially the Republic of China (ROC),[I][l] is a country[27] in East Asia.[o] It is located at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. The territories controlled by the ...
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Plasma was first identified in laboratory by Sir William Crookes. Crookes presented a lecture on what he called "radiant matter" to the British Association for the Advancement of Science, in Sheffield, on Friday, 22 August 1879.However, systematical studies of plasma began with the research of Irving Langmuirand his colleagues in 1920's. Langmuir a...
The fourth state of matter
Plasma is called the fourth state of matter after solid, liquid, and gas.It is a state of matter in which an ionized substance becomes highly electrically conductive to the point that long-range electric and magnetic fieldsdominate its behaviour. Plasma is typically an electrically quasineutral medium of unbound positive and negative particles (i.e. the overall charge of a plasma is roughly zero). Although these particles are unbound, they are not "free" in the sense of not experiencing force...
Ideal plasma
Three factors define an ideal plasma: 1. The plasma approximation: The plasma approximation applies when the plasma parameter Λ, representing the number of charge carriers within the Debye sphere is much higher than unity.It can be readily shown that this criterion is equivalent to smallness of the ratio of the plasma electrostatic and thermal energy densities. Such plasmas are called weakly coupled. 2. Bulk interactions: The Debye lengthis much smaller than the physical size of the plasma. T...
Non-neutral plasma
The strength and range of the electric force and the good conductivity of plasmas usually ensure that the densities of positive and negative charges in any sizeable region are equal ("quasineutrality"). A plasma with a significant excess of charge density, or, in the extreme case, is composed of a single species, is called a non-neutral plasma. In such a plasma, electric fields play a dominant role. Examples are charged particle beams, an electron cloud in a Penning trapand positron plasmas.
Density and ionization degree
For plasma to exist, ionization is necessary. The term "plasma density" by itself usually refers to the electron density n e {\\displaystyle n_{e}} , that is, the number of free electrons per unit volume. The degree of ionization α {\\displaystyle \\alpha } is defined as fraction of neutral particles that are ionized: 1. α = n i n i + n n {\\displaystyle \\alpha ={\\frac {n_{i}}{n_{i}+n_{n}}}} , where n i {\\displaystyle n_{i}} is the ion density and n n {\\displaystyle n_{n}} the neutral density (in...
Temperature
Plasma temperature, commonly measured in kelvin or electronvolts, is a measure of the thermal kinetic energy per particle. High temperatures are usually needed to sustain ionization, which is a defining feature of a plasma. The degree of plasma ionization is determined by the electron temperature relative to the ionization energy (and more weakly by the density). In thermal equilibrium, the relationship is given by the Saha equation. At low temperatures, ions and electrons tend to recombine i...
Plasma potential
Since plasmas are very good electrical conductors, electric potentials play an important role.[clarification needed] The average potential in the space between charged particles, independent of how it can be measured, is called the "plasma potential", or the "space potential". If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to what is termed a Debye sheath. The good electrical conductivity of plasmas makes their electric...
To completely describe the state of a plasma, all of theparticle locations and velocities that describe the electromagnetic field in the plasma region would need to be written down.However, it is generally not practical or necessary to keep track of all the particles in a plasma.[citation needed]Therefore, plasma physicists commonly use less detail...
Plasmas are the object of study of the academic field of plasma science or plasma physics, including sub-disciplines such as space plasma physics. It currently involves the following fields of active research and features across many journals, whose interest includes: Plasmas can appear in nature in various forms and locations, which can be usefull...
Although the underlying equations governing plasmas are relatively simple, plasma behaviour is extraordinarily varied and subtle: the emergence of unexpected behaviour from a simple model is a typical feature of a complex system. Such systems lie in some sense on the boundary between ordered and disordered behaviour and cannot typically be describe...
Hall effect thruster. The electric field in a plasma double layer is so effective at accelerating ions that electric fields are used in ion drives.Plasma sprayingTokamak plasma in nuclear fusion researchIntroduction to Plasma Physics: Graduate course given by Richard Fitzpatrick|M.I.T. Introduction by I.H.HutchinsonHow to make a glowing ball of plasma in your microwave with a grape|More (Video)CJK Unified Ideographs is a Unicode block containing the most common CJK ideographs used in modern Chinese, Japanese, Korean and Vietnamese characters. When contrasted with other blocks containing CJK Unified Ideographs, it is also referred to as the Unified Repertoire and Ordering (URO).[3] The block has hundreds of variation sequences ...
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m 2 ⋅s −3. [1] [2] [3] It is used to quantify the rate of energy transfer. The watt is named in honor of James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who ...
Wikipedia[note 3] is a free content online encyclopedia written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and the use of the wiki-based editing system MediaWiki. Wikipedia is the largest and most-read reference work in history.[3][4] It is consistently ranked as one of the ten most popular ...
e. Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Common phenomena are related to electricity, including lightning, static electricity ...
