Editing Bipolar junction transistor (section)

=== Early manufacturing techniques ===
Various methods of manufacturing bipolar transistors were developed.<ref>[http://hm-treasury.gov.uk/media/B/C/queen_mary_ip_research_institute_p5_043_762kb.pdf Third case study – the solid state advent] {{webarchive |url=https://web.archive.org/web/20070927032750/http://hm-treasury.gov.uk/media/B/C/queen_mary_ip_research_institute_p5_043_762kb.pdf |date=September 27, 2007 }} (PDF)</ref>
* [[Point-contact transistor]]&nbsp;– first transistor ever constructed (December 1947), a bipolar transistor, limited commercial use due to high cost and noise.
** [[Tetrode transistor#Early tetrode transistors|Tetrode point-contact transistor]] – Point-contact transistor having two emitters. It became obsolete in the middle 1950s.
* Junction transistors
** [[Grown-junction transistor]]{{spaced ndash}} first bipolar ''junction'' transistor made.<ref>{{cite web |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_M1752.htm |title=Transistor Museum, Historic Transistor Photo Gallery, Bell Labs Type M1752 }}</ref> Invented by William Shockley at [[Bell Labs]] on June 23, 1948.<ref>{{cite book |last=Morris |first=Peter Robin |title=A History of the World Semiconductor Industry |series=IEE History of Technology Series 12 |date=1990 |publisher=Peter Peregrinus Ltd. |location=London |isbn=978-0-86341-227-1 |page=29 |chapter=4.2 }}</ref> Patent filed on June 26, 1948.
** [[Alloy-junction transistor]]{{spaced ndash}} emitter and collector alloy beads fused to base. Developed at [[General Electric]] and [[RCA]]<ref>{{cite web |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_TA153.htm |title=Transistor Museum Photo Gallery RCA TA153 |access-date=August 10, 2016}}</ref> in 1951.
*** [[Micro-alloy transistor]] (MAT){{spaced ndash}} high-speed type of alloy junction transistor. Developed at [[Philco]].<ref>{{cite book |title=High Speed Switching Transistor Handbook |date=1963 |publisher=Motorola |edition=2nd |page=17}}[https://groups.google.com/group/sci.electronics.components/tree/browse_frm/month/2003-04/c97c04dc783ab61e?rnum=21&_done=%2Fgroup%2Fsci.electronics.components%2Fbrowse_frm%2Fmonth%2F2003-04%3F].</ref>
*** [[Micro-alloy diffused transistor]] (MADT){{spaced ndash}} high-speed type of alloy junction transistor, speedier than MAT, a [[diffused-base transistor]]. Developed at Philco.
*** [[Post-alloy diffused transistor]] (PADT){{spaced ndash}} high-speed type of alloy junction transistor, speedier than MAT, a diffused-base transistor. Developed at [[Philips]].
** [[Tetrode transistor]]{{spaced ndash}} high-speed variant of grown-junction transistor<ref>[http://semiconductormuseum.com/PhotoGallery/PhotoGallery_3N22.htm Transistor Museum, Historic Transistor Photo Gallery, Western Electric 3N22].</ref> or alloy junction transistor<ref>{{cite journal|doi=10.1109/T-ED.1957.14192|title=The tetrode power transistor|journal=IRE Transactions on Electron Devices|volume=4|issue=1|pages=1–5|date=1957|last=Maupin|first=J.T.|bibcode=1957ITED....4....1M|s2cid=51668235}}</ref> with two connections to base.
** [[Surface-barrier transistor]]{{spaced ndash}} high-speed metal-barrier junction transistor. Developed at Philco<ref>{{cite web |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_A01.htm |title=Transistor Museum Photo Gallery Philco A01 Germanium Surface Barrier Transistor |access-date=August 10, 2016 }}</ref> in 1953.<ref>{{cite web |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_SurfaceBarrier.htm |title=Transistor Museum Photo Gallery Germanium Surface Barrier Transistor |access-date=August 10, 2016 }}</ref>
** [[Drift-field transistor]]{{spaced ndash}} high-speed bipolar junction transistor. Invented by [[Herbert Kroemer]]<ref>{{cite journal |doi=10.1109/16.960370 |title=Herb's bipolar transistors |journal=IEEE Transactions on Electron Devices |volume=48 |issue=11 |pages=2473–2476 |date=2001 |last1=Brar |first1=B. |last2=Sullivan |first2=G.J. |last3=Asbeck |first3=P.M. |bibcode=2001ITED...48.2473B }}</ref><ref>{{cite journal |doi=10.1109/T-ED.1967.15902 |title=Influence of mobility and lifetime variations on drift-field effects in silicon-junction devices |journal=IEEE Transactions on Electron Devices |volume=14 |issue=2 |pages=75–81 |date=1967 |last1=Bullis |first1=W.M. |last2=Runyan |first2=W.R. |bibcode=1967ITED...14...75B }}</ref> at the Central Bureau of Telecommunications Technology of the German Postal Service, in 1953.
** [[Spacistor]]{{spaced ndash}} around 1957.
** [[Diffusion transistor]]{{spaced ndash}} modern type bipolar junction transistor. Prototypes<ref>{{cite web |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_Prototype_DiffusedBase.htm |title=Transistor Museum Photo Gallery Bell Labs Prototype Diffused Base Germanium Silicon Transistor |access-date=August 10, 2016}}</ref> developed at Bell Labs in 1954.
*** [[Diffused-base transistor]]{{spaced ndash}} first implementation of diffusion transistor.
*** [[Mesa transistor]]{{spaced ndash}} developed at [[Texas Instruments]] in 1957.
*** [[Planar transistor]]{{spaced ndash}} the bipolar junction transistor that made mass-produced monolithic integrated circuits possible. Developed by [[Jean Hoerni]]<ref>{{cite web |title=Transistor Museum Photo Gallery Fairchild 2N1613 Early Silicon Planar Transistor |url=http://semiconductormuseum.com/PhotoGallery/PhotoGallery_2N1613.htm |access-date=August 10, 2016 }}</ref> at [[Fairchild Semiconductor|Fairchild]] in 1959.
** Epitaxial transistor<ref>{{cite web |url=http://www.computerhistory.org/semiconductor/timeline/1960-Epitaxial.html |title=1960: Epitaxial Deposition Process Enhances Transistor Performance |publisher=Computer History Museum |access-date=June 22, 2023 }}</ref>{{spaced ndash}} a bipolar junction transistor made using vapor-phase deposition. See [[Epitaxy]]. Allows very precise control of doping levels and gradients.