Gallium nitride

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Gallium nitride
Image:Gallium nitride.jpg
General
Systematic name	Gallium(III) nitride
Other names	None Listed.
Molecular formula	GaN
Molar mass	83.7297 g/mol
Appearance	Yellow powder.
CAS number	[25617-97-4]
Properties
Density and phase	6.1 g/cm³, solid
Solubility in water	Reacts.
Melting point	>2500°C Template:Ref
Boiling point	-
Basicity (pK_b)	N/A
Hazards
MSDS	External MSDS
EU classification	None listed.
R-phrases	Template:R36, Template:R37, Template:R38, Template:R43.
S-phrases	Template:S24, Template:S37.
NFPA 704	N/A
Flash point	Non-flammable.
Supplementary data page
Structure and properties	n, ε_r, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Other anions	None listed.
Other cations	None listed.
Related bases	None listed.
Related compounds	InN, AlN
	GaP
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Gallium nitride (Ga{{#if:{{{1|}}}|_{{{1}}}}}N{{#if:{{{1|}}}|_{{{1}}}|}}) is a semiconductor material with wide (3.4 eV) band gap, used in optoelectronic, high-power and high-frequency devices. It is a binary group III/group V direct bandgap semiconductor. Its sensitivity to ionizing radiation is low (like other group III nitrides), making it a suitable material for solar cell arrays for satellites.

Until 1993, the only blue light-emitting devices commercially available were based on silicon carbide, which has an indirect bandgap, and so is not capable of sufficient brightness to be of wide interest.

The development of the first high-brightness GaN light-emitting diode (LED) by Shuji Nakamura, working for the Nichia company in Japan, completed the range of primary colors, and made possible applications such as daylight visible full-color LED displays, white LEDs and blue laser devices. GaN-based blue laser diodes are used in the Blu-ray disc technology, used in devices such as the Sony PlayStation 3.

The first GaN-based high-brightness LEDs were using a thin film of GaN deposited via MOCVD on sapphire. Other substrate used are zinc oxide, with lattice constant mismatch only 2%, and silicon carbide (SiC).

Potential markets for high-power/high-frequency devices based on GaN include microwave radio-frequency power amplifiers (such as used in high-speed wireless data transmission) and high-voltage switching devices for power grids. A potential mass-market application for GaN-based RF transistors is as the microwave source for microwave ovens, replacing the magnetrons currently used.

GaN, when doped with a suitable transition metal such as Manganese, is also a promising spintronics material. See Magnetic semiconductor.

GaN nanotubes have also been produced, with proposed applications in nanoscale electronics, optoelectronics and biochemical-sensing applications Template:Ref

GaN is a very hard, mechanically stable material with large heat capacity. In its pure form it resists cracking and can be deposited in thin film on sapphire, despite the mismatch in their lattice constants. GaN can be doped with silicon to N-type, however the silicon atoms change the way of the growth of the GaN crystals, introducing tensile stresses and making them brittle. GaN crystals are also rich in defects; 100 million to 10 billion per cm². [1]

Mixing GaN with InN yields InGaN, a semiconductor material with band gap dependent on ratio of InN to GaN and a high tolerance to lattice defects.

GaN and InGaN based parts are very sensitive to electrostatic discharge.

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