Substrate defects key to growth of 2-D materials

Creating two-dimentional materials large enough to use in electronics is a challenge despite huge effort but now, Penn State researchers have discovered a method for improving the quality of one class of 2-D materials, with ...

Smart pill bottle keeps drugs safe

Low-cost, stretchy sensors can be assembled inside the lid of a drug container to help monitor patient safety.

Flexible circuits for 3-D printing

A research collaborative between the University of Hamburg and DESY has developed a process suitable for 3-D printing that can be used to produce transparent and mechanically flexible electronic circuits. The electronics ...

A new energy-saving LED phosphor

The human eye is particularly sensitive to green, but less sensitive to blue and red. Chemists led by Hubert Huppertz at the University of Innsbruck have now developed a new red phosphor whose light is well perceived by the ...

New nanomaterial to replace mercury

The nano research team led by professors Helge Weman and Bjørn-Ove Fimland at the Norwegian University of Science and Technology's (NTNU) Department of Electronic Systems has succeeded in creating light-emitting diodes, ...

Record efficiency for perovskite-based light-emitting diodes

Efficient near-infrared (NIR) light-emitting diodes of perovskite have been produced in a laboratory at Linköping University. The external quantum efficiency is 21.6 percent, which is a record. The results have been published ...

Scientists build the smallest optical frequency comb to-date

Optical frequency combs are laser sources whose spectrum consists of a series of discrete, equally spaced frequency lines that can be used for precise measurements. In the last two decades, they have become a major tool for ...

Engineered light could improve health, food, suggests researcher

People who believe light-emitting diodes, or LEDS, are just an efficient upgrade to the ordinary electric light bulb are stuck in their thinking, suggest Sandia National Laboratories researcher Jeff Tsao and colleagues from ...

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In electronics, a diode is a two-terminal device (thermionic diodes may also have one or two ancillary terminals for a heater).

Diodes have two active electrodes between which the signal of interest may flow, and most are used for their unidirectional electric current property. The varicap diode is used as an electrically adjustable capacitor.

The unidirectionality most diodes exhibit is sometimes generically called the rectifying property. The most common function of a diode is to allow an electric current in one direction (called the forward biased condition) and to block the current in the opposite direction (the reverse biased condition). Thus, the diode can be thought of as an electronic version of a check valve.

Real diodes do not display such a perfect on-off directionality but have a more complex non-linear electrical characteristic, which depends on the particular type of diode technology. Diodes also have many other functions in which they are not designed to operate in this on-off manner.

Early diodes included “cat’s whisker” crystals and vacuum tube devices (also called thermionic valves). Today most diodes are made of silicon, but other semiconductors such a germanium are sometimes used.

This text uses material from Wikipedia, licensed under CC BY-SA