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A semiconductor device is an electronic component that relies on the electronic properties of a semiconductor material (primarily silicon, germanium, and gallium arsenide, as well as organic semiconductors) for its function.

Semiconductor devices have replaced vacuum tubes in most applications. They conduct electric current in the solid state, rather than as free electrons across a vacuum (typically liberated by thermionic emission) or as free electrons and ions through an ionized gas. Semiconductor devices are manufactured both as single discrete devices and as integrated circuits, which consist of two or more devices—which can number from the hundreds to the billions—manufactured and interconnected on a single semiconductor wafer (also called a substrate). Semiconductor materials are useful because their behavior can be easily manipulated by the deliberate addition of impurities, known as doping. Semiconductor conductivity can be controlled by the introduction of an electric or magnetic field, by exposure to light or heat, or by the mechanical deformation of a doped monocrystalline silicon grid; thus, semiconductors can make excellent sensors. Current conduction in a semiconductor occurs due to mobile or "free" electrons and electron holes, collectively known as charge carriers. Doping a semiconductor with a small proportion of an atomic impurity, such as phosphorus or boron, greatly increases the number of free electrons or holes within the semiconductor. When a doped semiconductor contains excess holes, it is called a p-type semiconductor (p for positive electric charge); when it contains excess free electrons, it is called an n-type semiconductor (n for a negative electric charge). The manufacture of semiconductors controls precisely the location and concentration of p- and n-type dopants. The most common semiconductor device in the world is the MOSFET (metal–oxide–semiconductor field-effect transistor), also called the MOS transistor.

A semiconductor diode is a device typically made from a single p–n junction. At the junction of a p-type and an n-type semiconductor, there forms a depletion region where current conduction is inhibited by the lack of mobile charge carriers.

Another type of transistor, the field-effect transistor (FET), operates on the principle that semiconductor conductivity can be increased or decreased by the presence of an electric field. The field may be applied by a reverse-biased p–n junction, forming a junction field-effect transistor (JFET) or by an electrode insulated from the bulk material by an oxide layer, forming a metal–oxide–semiconductor field-effect transistor (MOSFET).

The metal-oxide-semiconductor FET (MOSFET, or MOS transistor), a solid-state device, is by far the most used widely semiconductor device today.

By far, silicon (Si) is the most widely used material in semiconductor devices. Silicon used in semiconductor device manufacturing is currently fabricated into boules that are large enough in diameter to allow the production of 300 mm (12 in.) wafers.

Power semiconductor devices are discrete devices or integrated circuits intended for high current or high voltage applications. Power integrated circuits combine IC technology with power semiconductor technology, these are sometimes referred to as "smart" power devices.

Another early type of semiconductor device is the metal rectifier in which the semiconductor is copper oxide or selenium.

After the war, William Shockley decided to attempt the building of a triode-like semiconductor device. When current flowed through this "base" lead, the electrons or holes would be pushed out, across the block of the semiconductor, and collect on the far surface.

Bell Telephone Laboratories needed a generic name for their new invention: "Semiconductor Triode", "Solid Triode", "Surface States Triode" , "Crystal Triode" and "Iotatron" were all considered, but "transistor", coined by John R.

At Shockley Semiconductor, Shockley had circulated the preprint of their article in December 1956 to all his senior staff, including Jean Hoerni, who would later invent the planar process in 1959 while at Fairchild Semiconductor. Following this research, Mohamed Atalla and Dawon Kahng proposed a silicon MOS transistor in 1959 and successfully demonstrated a working MOS device with their Bell Labs team in 1960.

Quick Facts

• When a doped semiconductor contains excess holes, it is called a p-type semiconductor (p for positive electric charge); when it contains excess free electrons, it is called an n-type semiconductor (n for a negative electric charge).
• The most common semiconductor device in the world is the MOSFET (metal–oxide–semiconductor field-effect transistor), also called the MOS transistor.
• Semiconductor devices are manufactured both as single discrete devices and as integrated circuits, which consist of two or more devices—which can number from the hundreds to the billions—manufactured and interconnected on a single semiconductor wafer (also called a substrate).
• Doping a semiconductor with a small proportion of an atomic impurity, such as phosphorus or boron, greatly increases the number of free electrons or holes within the semiconductor.
• Current conduction in a semiconductor occurs due to mobile or "free" electrons and electron holes, collectively known as charge carriers.

Source material: Wikipedia - "Semiconductor device". Adapted and summarized for DiscoverScroll. Original contributors are credited through the linked Wikipedia article. Read original on Wikipedia. CC BY-SA 4.0. Changes were made from the original.