Diode

Diode
John Maushammer; The original uploader was Morcheeba at English Wikipedia. · CC BY-SA 2.5 · source
Name	Diode
Type	Semiconductor device
Invented	1904 (cat's whisker era)
Inventor	Multiple

Diode

A diode is a two-terminal semiconductor device that permits current flow primarily in one direction, used in Bell Labs, Texas Instruments, Intel, RCA and Sony products and systems. It appears across technologies developed at Bell Laboratories, AT&T, General Electric, IBM and Motorola and is fundamental to circuits in NASA probes, Siemens infrastructure, Siemens-Schuckert, Lockheed Martin avionics and consumer electronics from Apple Inc. and Samsung Electronics. Designers from Stanford University, Massachusetts Institute of Technology, University of Cambridge and ETH Zurich refined its theories alongside researchers at Western Electric and Philips.

Overview

Diodes are basic elements used in rectifiers found in Harvard University labs, signal limiters used by Raytheon Technologies and switching networks used in Hewlett-Packard instrumentation; they bridge work at Bell Labs, Princeton University, Caltech and University of Illinois Urbana-Champaign. Common categories were adopted by standards bodies such as IEEE and IEC and they appear in military specifications from Department of Defense programs and space-qualified parts for European Space Agency missions. Semiconductor companies like Infineon Technologies, STMicroelectronics, NXP Semiconductors and ON Semiconductor supply diodes for systems produced by Boeing, Airbus, Panasonic and LG Electronics.

History

Early investigations at Marconi Company and University of Manchester into rectification led to devices such as the cat's whisker detector used in Marconi wireless receivers and commercialized by De Forest and Fessenden; later work at Bell Labs and Western Electric produced vacuum diodes and thermionic devices applied in RCA radios and ENIAC computing hardware. The invention of the semiconductor junction by researchers at Bell Labs including teams led by William Shockley and contemporaries at Texas Instruments and H. J. Round evolved through milestones like the Transistor development, patents filed by John Bardeen and Walter Brattain, and manufacturing advances from Sylvania and Fairchild Semiconductor. Postwar research at IBM Research, Sandia National Laboratories and National Physical Laboratory (UK) expanded compound semiconductor diodes used in radar systems by MIT Lincoln Laboratory and in optoelectronics developed by Bell Labs and Corning Incorporated.

Types and Materials

Silicon, germanium and compound semiconductors such as gallium arsenide, gallium nitride and silicon carbide are main materials used by firms like Intel Corporation, Nvidia and Cree, Inc. for signal diodes, Schottky diodes, Zener diodes, tunnel diodes, light-emitting diodes and laser diodes applied in devices from Sony Corporation and Canon Inc.. Power diodes built by Infineon and STMicroelectronics are often silicon carbide or silicon; Schottky diodes used by Texas Instruments and Analog Devices exploit metal–semiconductor junctions. Light-emitting and laser diodes are manufactured by Osram, Nichia, Lumileds and II-VI Incorporated for displays and fiber-optic transmitters used by Corning and Nokia.

Operating Principles

A PN junction, formed in processes refined at Bell Labs and Fairchild Semiconductor, underpins rectification and switching behavior; carriers studied by Shockley and modeled in textbooks from MIT Press and Cambridge University Press move under built-in potentials and external biasing. Forward bias reduces the depletion region enabling majority and minority carrier injection as described in work by William Shockley and Walter Schottky; reverse bias expands the depletion region and can lead to breakdown mechanisms characterized by Zener and avalanche effects investigated at Bell Labs and University of California, Berkeley. Quantum tunneling underlies Esaki (tunnel) diodes developed at Sony and Tokyo University, while heterojunctions in gallium arsenide devices were advanced at Bell Labs and University of Illinois.

Characteristics and Parameters

Key parameters—forward voltage drop, reverse breakdown voltage, leakage current, reverse recovery time and junction capacitance—are specified by datasheets from Vishay Intertechnology, Rohm Semiconductor and Diodes Incorporated and standardized through JEDEC committees and MIL-STD documents. Performance metrics such as thermal resistance and power dissipation are critical in applications by Tesla, Inc. and ABB; reliability testing protocols come from Underwriters Laboratories and qualification labs at NIST and ESA.

Applications

Diodes serve in power conversion for Siemens substations, signal demodulation in receivers built by Thales Group, protection in telecommunication equipment from Ericsson and Huawei, and in lighting systems by Philips Lighting and Cree. Photodiodes and laser diodes are central to fiber-optic links used by AT&T, Verizon Communications and submarine cable operators; LEDs form displays by Samsung Display and indicator systems for General Motors and Toyota Motor Corporation. High-speed diodes are crucial in radar and microwave work at Raytheon, Lockheed Martin and BAE Systems.

Manufacturing and Packaging

Manufacturing techniques developed at Fairchild Semiconductor, Intel fabs and TSMC include photolithography, diffusion and ion implantation with process control by equipment from ASML, Applied Materials and KLA Corporation. Packaging choices—from through-hole packages by TE Connectivity to surface-mount packages produced by Amphenol—involve encapsulation, thermal vias and lead-frame design for automotive-grade parts specified by ISO and SAE International. Test and burn-in are performed in facilities run by Jabil and Foxconn for consumer devices from Amazon and Microsoft.

Category:Semiconductor devices