Editing Doping (semiconductor) (section)

==History==
The effects of impurities in semiconductors (doping) were long known empirically in such devices as [[crystal radio]] [[Cat's-whisker detector|detectors]] and [[selenium rectifiers]]. For instance, in 1885 [[Shelford Bidwell]], and in 1930 the German scientist Bernhard Gudden, each independently reported that the properties of semiconductors were due to the impurities they contained.<ref>{{cite web|url=https://sites.google.com/site/transistorhistory/faraday-to-shockley |title=Faraday to Shockley – Transistor History |access-date=2016-02-02}}{{self-published inline|date=May 2025}}</ref><ref>{{cite book |last1=Wilson |first1=A. H. |title=The theory of metals |date=1954 |publisher=Cambridge University Press |url=https://archive.org/details/theoryofmetals00wils |oclc=1036891562 }}{{pn|date=May 2025}}</ref> 
A doping process was formally developed by [[John Robert Woodyard]] working at [[Sperry Gyroscope Company]] during [[World War II]]. Though the word ''doping'' is not used in it, his US Patent issued in 1950 describes methods for adding tiny amounts of solid elements from the nitrogen column of the periodic table to germanium to produce rectifying devices.<ref>{{cite patent |inventor=Woodyard, John R. |title=Nonlinear circuit device utilizing germanium |country=US |status=patent|number=2530110 |fdate=1944 |gdate=1950}}</ref> The demands of his work on [[radar]] prevented Woodyard from pursuing further research on semiconductor doping.

Similar work was performed at [[Bell Labs]] by [[Gordon K. Teal]] and [[Morgan Sparks]], with a US Patent issued in 1953.<ref>{{cite patent |invent1=Sparks, Morgan |invent2=Teal, Gordon K. |title=Method of Making P-N Junctions in Semiconductor Materials |country=US |status=patent|number=2631356 |fdate=June 15, 1950 |gdate=March 17, 1953}}</ref>

Woodyard's prior [[patent]] proved to be the grounds of extensive litigation by [[Sperry Rand]].<ref>{{cite news|year=1985|work=University of California: In Memoriam|title=John Robert Woodyard, Electrical Engineering: Berkeley|access-date=2007-08-12|url=http://content.cdlib.org/view?docId=hb4d5nb20m&doc.view=frames&chunk.id=div00182&toc.depth=1&toc.id=&brand=calisphere}}</ref>