Editing Gallium (section)

===Semiconductors===
[[File:Blue LED and Reflection.jpg|thumb|Gallium-based blue LEDs]]
Extremely high-purity (>99.9999%) gallium is commercially available to serve the [[semiconductor]] industry. [[Gallium arsenide]] (GaAs) and [[gallium nitride]] (GaN) used in electronic components represented about 98% of the gallium consumption in the United States in 2007. About 66% of semiconductor gallium is used in the U.S. in integrated circuits (mostly gallium arsenide), such as the manufacture of ultra-high-speed logic chips and [[MESFET]]s for low-noise microwave preamplifiers in cell phones. About 20% of this gallium is used in [[optoelectronic]]s.<ref name="USGSCS2008">{{cite web|url= http://minerals.usgs.gov/minerals/pubs/commodity/gallium/mcs-2008-galli.pdf |archive-url=https://web.archive.org/web/20080514204029/http://minerals.usgs.gov/minerals/pubs/commodity/gallium/mcs-2008-galli.pdf |archive-date=14 May 2008 |url-status=live|title= Mineral Commodity Summary 2006: Gallium|publisher= United States Geological Survey|access-date= 20 November 2008|first= Deborah A.|last= Kramer}}</ref>

Worldwide, gallium arsenide makes up 95% of the annual global gallium consumption.<ref name="Moskalyk" /> It amounted to $7.5&nbsp;billion in 2016, with 53% originating from cell phones, 27% from wireless communications, and the rest from automotive, consumer, fiber-optic, and military applications. The recent increase in GaAs consumption is mostly related to the emergence of [[3G]] and [[4G]] [[smartphone]]s, which employ up to 10 times the amount of GaAs in older models.<ref name="usgs2018" />

Gallium arsenide and gallium nitride can also be found in a variety of optoelectronic devices which had a market share of $15.3&nbsp;billion in 2015 and $18.5&nbsp;billion in 2016.<ref name="usgs2018" /> [[Aluminium gallium arsenide]] (AlGaAs) is used in high-power infrared laser diodes. The semiconductors gallium nitride and [[indium gallium nitride]] are used in blue and violet optoelectronic devices, mostly [[laser diode]]s and [[light-emitting diode]]s. For example, gallium nitride 405&nbsp;nm diode lasers are used as a violet light source for higher-density [[Blu-ray Disc]] compact data disc drives.<ref>{{cite book |url= https://books.google.com/books?id=pVkhYTzdXgoC&pg=PA150 |pages= 150–151 |title= Advances in Semiconductor Lasers |isbn= 978-0-12-391066-0 |last1= Coleman |first1= James J. |last2= Jagadish |first2= Chennupati |last3= Catrina Bryce |first3= A. |date= 2 May 2012|publisher= Academic Press }}</ref>

Other major applications of gallium nitride are cable television transmission, commercial wireless infrastructure, power electronics, and satellites. The GaN radio frequency device market alone was estimated at $370&nbsp;million in 2016 and $420&nbsp;million in 2016.<ref name="usgs2018" />

[[Multijunction photovoltaic cell]]s, developed for [[satellite]] power applications, are made by [[molecular-beam epitaxy]] or [[metalorganic vapour-phase epitaxy]] of [[thin film]]s of gallium arsenide, [[indium gallium phosphide]], or [[indium gallium arsenide]]. The [[Mars Exploration Rover]]s and several satellites use triple-junction gallium arsenide on germanium cells.<ref>{{cite journal|doi= 10.1016/S0094-5765(02)00287-4 |title= The performance of gallium arsenide/germanium solar cells at the Martian surface |date= 2004 |first= D.|last= Crisp |author2= Pathare, A. |author3=Ewell, R. C. |journal= Acta Astronautica |volume= 54|pages= 83–101|issue= 2|bibcode= 2004AcAau..54...83C}}</ref> Gallium is also a component in [[photovoltaic]] compounds (such as copper indium gallium selenium sulfide {{chem2|Cu(In,Ga)(Se,S)2}}) used in solar panels as a cost-efficient alternative to [[crystalline silicon]].<ref>{{cite journal |title= Material and device properties of single-phase Cu(In,Ga)(Se,S)<sub>2</sub> alloys prepared by selenization/sulfurization of metallic alloys |first= V.|last= Alberts |author2= Titus J. |author3= Birkmire R. W. |journal= Thin Solid Films |volume= 451–452|pages= 207–211 |date= 2003 |doi= 10.1016/j.tsf.2003.10.092|bibcode= 2004TSF...451..207A}}</ref>