All Categories
History
This section provides an overview for gunn diodes as well as their applications and principles. Also, please take a look at the list of 6 gunn diode manufacturers and their company rankings. Here are the top-ranked gunn diode companies as of December, 2024: 1.MicroWave Technology, Inc., 2.Teledyne Lincoln Microwave, 3.Hybrid Electronics Corporation.
Table of Contents
A Gunn diode is a type of diode used in microwave band oscillators and other devices.
Gunn diodes are diodes that utilize the Gunn effect. N-type gallium arsenide (GaAs) is mainly used, and physicist J.B. Gunn discovered that when a DC electric field is applied to a GaAs crystal and exceeds a certain threshold value, oscillation occurs in the microwave region. For this reason, this phenomenon is called the Gunn effect.
Gunn diodes have a region of negative resistance, and this effect is used in microwave oscillators. Negative resistance here refers to the electrical characteristic that current decreases as voltage increases.
Gunn diodes are commonly used in the microwave region for oscillator radar applications using the Gunn effect.
When a Gunn diode is mounted in a cavity or waveguide and a DC voltage is applied, it oscillates with an intrinsic vibration that depends on the thickness of the crystal. Although the structure is relatively simple, the frequency stability is not as good as that of the usual microwave control method using a VCO or PLL, so it is often used for speed sensors using the Doppler effect in addition to communications.
Familiar applications include speed guns for baseball and radar for speed enforcement.
Gunn diodes take advantage of the microwave band oscillation phenomenon that occurs when electrons rapidly transition to the band with the higher energy level when a voltage exceeding the critical electric field is applied to a semiconductor crystal with two energy bands. When a graph of energy is drawn, it has two conduction bands with different bottom energies and wave numbers.
When voltage is applied, an electric current flows, and the electrons responsible for this current are those in the conduction band. Normally, more electrons exist in the conduction band with lower energy at the bottom, and as the voltage increases, more electrons are in the conduction band with higher energy. When a certain voltage is exceeded, electrons from the lower level conduction band move to the higher level conduction band, resulting in a decrease in mobility.
This phenomenon causes a decrease in the apparent mobility of electrons, or current, when the voltage is increased above a certain voltage, and thus has the characteristic of negative resistance. As the voltage is further increased, the electrons in the lower level conduction band are transferred to the higher level conduction band, and the current increases again.
At this point, an avalanche of rapid, high-speed electron transfer occurs in the microwave band, resulting in the oscillation phenomenon. While general VCOs (voltage-controlled oscillators) utilize a negative resistance that takes advantage of the impedance matching of transistors, Gunn diodes make good use of the inherent energy bands of semiconductor crystals.
Velocity sensors, a typical application of Gunn diodes, generally use a physical phenomenon called the Doppler effect. The Doppler effect is the principle that the reflected wave of an electromagnetic wave irradiated onto an object moving at high speed is observed at a different apparent frequency than the original frequency of the irradiation.
The frequency of a Gunn diode in a GaAs crystal is about 10 GHz, and the speed of the irradiated object is calculated from the difference in frequency variation. Incidentally, this difference in frequency variation is described as a "whirr" in physical terms, and the variation relative to a frequency of 10 GHz is a very small percentage for speed measurements in the 100 km range for baseball speed guns and automobile speed measurements.
Gunn diodes and similar diodes, as well as resonant tunneling diodes, are currently the focus of attention in research institutions as research materials for sub-terahertz frequency oscillators.
*Including some distributors, etc.
Sort by Features
Sort by Area
Microchip Technology Incorporated was incorporated in 1989 and is headquartered in Chandler, Arizona. The company is a developer and manufacturer of control solutions for global markets including the automotive, industrial, communications, human-machine interface, and connectivity industries. The company’s products include microcontrollers, field-programmable gate array products, MOSFET and radio frequency products, and both wired and wireless communications products. The company’s services include wafer foundry and assembly services, test subcontracting manufacturing services, development tools for enabling system designers to program microcontrollers and processors, and timing system products.
MicroWave Technology (MwT) is a manufacturer of RF, microwave and wireless products headquartered in Fremont, California. The company was founded in 1982. The company's product list includes MMICs, discrete semiconductor devices, standard modular amplifier products to 26 GHz, and low noise pHEMT parts. They also design and manufacture hybrid products, pre-amplifiers for medical applications (MRI coils), and connectorized amplifiers. MwT assembles, tests, screens, and conducts qualification testing on microwave semiconductor devices, components, and sub-systems. Their products are used in military and space applications and other industries.
Microsemi Corporation was founded in 1959 and is headquartered in Aliso Viejo, California. Microsemi is a subsidiary of Microchip Technology Incorporated. Microsemi is a provider of semiconductor and system solutions for aerospace, communications, data center, and industrial markets. A few of Microsemi’s product lines include high-performance and radiation-hardened analog mixed-signal integrated circuits, FPGAs, power management products, timing and synchronization devices, and RF solutions. Microsemi’s technological strengths are in connectivity, energy efficiency, miniaturization, power management, and security.
HoverLabs has roots dating back to 1963 and is headquartered in Haryana, India. The company is a laboratory supplies manufacturer, exporting to over 110 countries. The company provides extensive R&D for designing, manufacturing, and packaging supplies. The company also provides customized product development, OEM support, and project management assistance. The company’s products include educational equipment, analytical lab equipment, engineering lab equipment, medical lab equipment, and other products used in the medical as well as scientific industries.
Teledyne Lincoln Microwave, established in 1947, is a manufacturer of microwave products and components located in Lincoln, UK. Being part of the Teledyne Defense Electronics group, the company has been a supplier of ITAR-Free microwave products for over 70 years. The company specializes in custom or semi-custom design and manufacturing in small to medium-sized batch quantities, serving various industrial markets with long-standing business units across the US and UK. Their product range encompasses components and systems for defense, space, security, and commercial RF and Microwave applications including RF, relays, coax switches, microwaves, and others.
Hybrid Electronics is a global distribution specialist of electronic components, with access to over 50 million unique components. Among the markets HE serves are the aerospace, automotive, communications, defense, industrial, medical, national security, and test & measurement industries. In addition to components, HE also provides quality and compliance testing, counterfeit detection, upscreening, and other forms of quality control. Examples of component subtypes that HE offers include ICs, batteries, capacitors, semiconductor products, sensors, circuit protection, interconnectors, filters, optoelectronics, relays, switches, power supplies, and cables and cable assemblies.
Ranking as of December 2024
Derivation Method| Rank | Company | Click Share |
|---|---|---|
| 1 | MicroWave Technology, Inc. |
21.5%
|
| 2 | HOVERLABS |
19.7%
|
| 3 | Microchip Technology Inc. |
17.2%
|
| 4 | Teledyne Lincoln Microwave |
16.7%
|
| 5 | Hybrid Electronics Corporation |
16.7%
|
| 6 | Microsemi Corporation |
8.2%
|
Derivation Method
The ranking is calculated based on the click share within the gunn diode page as of December 2024. Click share is defined as the total number of clicks for all companies during the period divided by the number of clicks for each company.Number of Employees
Newly Established Company
Company with a History
*Including some distributors, etc.
*Including some distributors, etc.
| Country | Number of Companies | Share (%) |
|---|---|---|
|
United States of America
|
3 | 60.0% |
|
India
|
1 | 20.0% |
|
United Kingdom
|
1 | 20.0% |
