Electric currentAn electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge carriers, which may be one of several types of particles, depending on the conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or holes.
Spin structureIn differential geometry, a spin structure on an orientable Riemannian manifold (M, g) allows one to define associated spinor bundles, giving rise to the notion of a spinor in differential geometry. Spin structures have wide applications to mathematical physics, in particular to quantum field theory where they are an essential ingredient in the definition of any theory with uncharged fermions. They are also of purely mathematical interest in differential geometry, algebraic topology, and K theory.
Metal–semiconductor junctionIn solid-state physics, a metal–semiconductor (M–S) junction is a type of electrical junction in which a metal comes in close contact with a semiconductor material. It is the oldest practical semiconductor device. M–S junctions can either be rectifying or non-rectifying. The rectifying metal–semiconductor junction forms a Schottky barrier, making a device known as a Schottky diode, while the non-rectifying junction is called an ohmic contact.
Semiconductor packageA semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers (commonly silicon) before being diced into die, tested, and packaged. The package provides a means for connecting it to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure.
Electronic circuitAn electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow. It is a type of electrical circuit and to be referred to as electronic, rather than electrical, generally at least one active component must be present. The combination of components and wires allows various simple and complex operations to be performed: signals can be amplified, computations can be performed, and data can be moved from one place to another.
Almost complex manifoldIn mathematics, an almost complex manifold is a smooth manifold equipped with a smooth linear complex structure on each tangent space. Every complex manifold is an almost complex manifold, but there are almost complex manifolds that are not complex manifolds. Almost complex structures have important applications in symplectic geometry. The concept is due to Charles Ehresmann and Heinz Hopf in the 1940s. Let M be a smooth manifold.
MajorityA majority, also called a simple majority or absolute majority to distinguish it from related terms, is more than half of the total. It is a subset of a set consisting of more than half of the set's elements. For example, if a group consists of 20 individuals, a majority would be 11 or more individuals, while having 10 or fewer individuals would not constitute a majority. "Majority" can be used to specify the voting requirement, as in a "majority vote", which means more than half of the votes cast.
Anderson's ruleAnderson's rule is used for the construction of energy band diagrams of the heterojunction between two semiconductor materials. Anderson's rule states that when constructing an energy band diagram, the vacuum levels of the two semiconductors on either side of the heterojunction should be aligned (at the same energy). It is also referred to as the electron affinity rule, and is closely related to the Schottky–Mott rule for metal–semiconductor junctions. Anderson's rule was first described by R. L. Anderson in 1960.
Standard cellIn semiconductor design, standard-cell methodology is a method of designing application-specific integrated circuits (ASICs) with mostly digital-logic features. Standard-cell methodology is an example of design abstraction, whereby a low-level very-large-scale integration (VLSI) layout is encapsulated into an abstract logic representation (such as a NAND gate). Cell-based methodology – the general class to which standard cells belong – makes it possible for one designer to focus on the high-level (logical function) aspect of digital design, while another designer focuses on the implementation (physical) aspect.
Majority ruleMajority rule is the principle that the group that has the most supporters gets its way. A majority is more than half of the voters involved, and rule by such a majority is thought to be to the benefit of more than rule by less than half (a mere minority) would be. Majority rule is the binary decision rule most often used in decision-making bodies, including many legislatures of democratic nations. Where no one party wins a majority of the seats in a legislature, the majority of legislators that wields power is partly composed of members of other parties in support.
Self-aligned gateIn semiconductor electronics fabrication technology, a self-aligned gate is a transistor manufacturing approach whereby the gate electrode of a MOSFET (metal–oxide–semiconductor field-effect transistor) is used as a mask for the doping of the source and drain regions. This technique ensures that the gate is naturally and precisely aligned to the edges of the source and drain. The use of self-aligned gates in MOS transistors is one of the key innovations that led to the large increase in computing power in the 1970s.
CMOSComplementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss", siːmɑːs, -ɒs) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips (including CMOS BIOS), and other digital logic circuits.
