Editing Germanium (section)

=== Electronics ===
Germanium can be alloyed with [[silicon]], and [[silicon–germanium]] alloys are rapidly becoming an important semiconductor material for high-speed integrated circuits. Circuits using the properties of Si-SiGe [[heterojunction]]s can be much faster than those using silicon alone.<ref>{{cite journal |doi=10.1109/TED.2003.810484 |title=SiGe HBT and BiCMOS technologies for optical transmission and wireless communication systems |date=2003 |last=Washio |first=K. |journal=IEEE Transactions on Electron Devices |volume=50 |issue=3 |pages=656–668 |bibcode=2003ITED...50..656W}}</ref> The SiGe chips, with high-speed properties, can be made with low-cost, well-established production techniques of the [[silicon chip]] industry.<ref name="usgs" />

High efficiency [[solar panel]]s are a major use of germanium. Because germanium and [[gallium arsenide]] have nearly identical [[lattice constant]], germanium substrates can be used to make gallium-arsenide [[solar cell]]s.<ref>{{cite journal |doi=10.1002/pip.446 |title=Space and terrestrial photovoltaics: synergy and diversity |date=2002 |last1=Bailey |first1=Sheila G. |journal=Progress in Photovoltaics: Research and Applications |volume=10 |issue=6 |pages=399–406 |last2=Raffaelle |first2=Ryne |last3=Emery |first3=Keith |hdl=2060/20030000611 |bibcode=2002sprt.conf..202B |s2cid=98370426 |hdl-access=free}}</ref> Germanium is the substrate of the wafers for high-efficiency [[multijunction photovoltaic cell]]s for space applications, such as the [[Mars Exploration Rover]]s, which 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=January 2004 |first=D. |last=Crisp |author2=Pathare, A. |author3=Ewell, R. C. |journal=Acta Astronautica |volume=54 |issue=2 |pages=83–101 |bibcode=2004AcAau..54...83C}}</ref> High-brightness LEDs, used for automobile headlights and to backlight LCD screens, are also an important application.<ref name="usgs" />

Germanium-on-insulator (GeOI) substrates are seen as a potential replacement for silicon on miniaturized chips.<ref name="usgs" /> CMOS circuit based on GeOI substrates has been reported recently.<ref>{{cite journal |first1=Heng |last1=Wu |first2=Peide D. |last2=Ye |date=August 2016 |title=Fully Depleted Ge CMOS Devices and Logic Circuits on Si |journal=[[IEEE Transactions on Electron Devices]] |volume=63 |issue=8 |pages=3028–3035 |doi=10.1109/TED.2016.2581203 |bibcode=2016ITED...63.3028W |s2cid=3231511 |url=https://engineering.purdue.edu/~yep/Papers/TED_Ge%20Fully%20Depleted%20CMOS_2016.pdf |access-date=2019-03-04 |archive-date=2019-03-06 |archive-url=https://web.archive.org/web/20190306044456/https://engineering.purdue.edu/~yep/Papers/TED_Ge%20Fully%20Depleted%20CMOS_2016.pdf |url-status=live}}</ref> Other uses in electronics include [[phosphor]]s in [[fluorescent lamp]]s<ref name="lanl" /> and solid-state light-emitting diodes (LEDs).<ref name="usgs" /> Germanium transistors are still used in some [[effects pedal]]s by musicians who wish to reproduce the distinctive tonal character of the [[Distortion (music)|"fuzz"-tone]] from the early [[rock and roll]] era, most notably the [[Fuzz Face|Dallas Arbiter Fuzz Face]].<ref>{{cite journal |author=Szweda, Roy |date=2005 |title=Germanium phoenix |journal=[[III-Vs Review]] |volume=18 |issue=7 |page=55 |doi=10.1016/S0961-1290(05)71310-7}}</ref>

Germanium has been studied as a potential material for implantable bioelectronic sensors that are [[Biodegradable electronics|resorbed]] in the body without generating harmful hydrogen gas, replacing [[zinc oxide]]- and [[indium gallium zinc oxide]]-based implementations.<ref>{{ cite journal |last1=Zhao |first1=H. |last2=Xue |first2=Z. |last3=Wu |first3=X. |display-authors=2 |date=21 July 2022 |title=Biodegradable germanium electronics for integrated biosensing of physiological signals. |journal=npj Flexible Electronics |volume=6 |at=63 |doi=10.1038/s41528-022-00196-2 |s2cid=250702946 |doi-access=free}}</ref>

Germanium was also used to create many of the circuits found in some of the very first pieces of electronic musical gear, initially 1950s, primarily in early transistor-based circuits. The first guitar effects pedals in the 1960s – Fuzz pedals like the Maestro FZ-1 (1962), Dallas-Arbiter Fuzz Face (1966), and Tone Bender (1965) - used germanium transistors.<ref>{{Cite web |last=joe |date=2012-01-03 |title=The Germanium Mystique |url=https://tonefiend.com/diy/the-germanium-mystique/ |access-date=2025-02-21 |website=tonefiend.com |language=en-US}}</ref> Silicon diodes are more frequently used in more modern equipment, but germanium diodes are still used in some applications as they have lower barrier potential and smoother [[transconductance]] curves, leading to less harsh [[Clipping (audio)|clipping]].<ref>{{Citation |last=Dailey |first=Denton J. |title=Guitar Effects Circuits |date=2013 |work=Electronics for Guitarists |pages=199–200 |url=https://link.springer.com/chapter/10.1007/978-1-4614-4087-1_5 |access-date=2025-02-21 |place=New York, NY |publisher=Springer New York |language=en |doi=10.1007/978-1-4614-4087-1_5 |isbn=978-1-4614-4086-4}}</ref>