Carl Frosch

{{Short description|American scientist (1908–1984)}}

{{about|the scientist|the boxer|Carl Froch}}File:1957(Figure 9)-Gate oxide transistor by Frosch and Derrick.pngCarl John[https://books.google.com/books?id=wQhAJRWW_O4C&q= "Carl+John+Frosch" The Canadian Patent Office Record and Register of Copyrights and Trade Marks, Volume 77, Issues 36-43] Frosch (September 6, 1908 – May 18, 1984)[https://www.findagrave.com/memorial/16288995 Carl J Frosch (1908-1984)], Find A Grave was a Bell Labs researcher who along Lincoln Derick build the first silicon dioxide field effect transistors. In 1955 they accidentally discovered that silicon could be protectively coated by silicon dioxide by the right exposure to oxygen when hot, and patented the method.{{Cite journal |last=Huff |first=Howard |last2=Riordan |first2=Michael |date=2007-09-01 |title=Frosch and Derick: Fifty Years Later (Foreword) |url=https://iopscience.iop.org/article/10.1149/2.F02073IF |journal=The Electrochemical Society Interface |volume=16 |issue=3 |pages=29–29 |doi=10.1149/2.F02073IF |issn=1064-8208}}{{Cite patent|number=US2802760A|title=Oxidation of semiconductive surfaces for controlled diffusion|gdate=1957-08-13|invent1=Lincoln|invent2=Frosch|inventor1-first=Derick|inventor2-first=Carl J.|url=https://patents.google.com/patent/US2802760A}} Such protective coating overcame a problem of surface states found in active silicon circuit elements. The discovery also revealed the potential for the process of silicon etching. File:1957(Figure 7)-Gate oxide transistor by Frosch and Derrick.png

In 1957 Frosch and Derick published their discovery of silicon surface passivation by silicon dioxide, using selective SiO2 predeposition and masking to produce semiconductor surface patterns, to build silicon dioxide field effect transistors, thus devising the first MOSFET.{{Cite journal |last1=Frosch |first1=C. J. |last2=Derick |first2=L. |date=1957-09-01 |title=Surface Protection and Selective Masking during Diffusion in Silicon |url=https://iopscience.iop.org/article/10.1149/1.2428650 |journal=Journal of the Electrochemical Society |language=en |volume=104 |issue=9 |pages=547 |doi=10.1149/1.2428650 |issn=1945-7111}} Their transistors were the first in which drain and source were adjacent at the surface, showing that silicon dioxide surface passivation protected and insulated silicon wafers.

At Bell Labs, the importance of Frosch's technique was immediately realized. Results of their work circulated around Bell Labs in the form of BTL memos before being published in 1957. At Shockley Semiconductor, William Shockley had circulated the preprint of their article in December 1956 to all his senior staff, including Jean Hoerni.{{cite book |last1=Moskowitz |first1=Sanford L. |url=https://books.google.com/books?id=2STRDAAAQBAJ&pg=PA168 |title=Advanced Materials Innovation: Managing Global Technology in the 21st century |date=2016 |publisher=John Wiley & Sons |isbn=978-0-470-50892-3 |page=168}}{{cite book |author1=Christophe Lécuyer |url=https://books.google.com/books?id=LaZpUpkG70QC&pg=PA62 |title=Makers of the Microchip: A Documentary History of Fairchild Semiconductor |author2=David C. Brook |author3=Jay Last |date=2010 |publisher=MIT Press |isbn=978-0-262-01424-3 |pages=62–63}}{{cite book |last1=Claeys |first1=Cor L. |url=https://books.google.com/books?id=bu22JNYbE5MC&pg=PA27 |title=ULSI Process Integration III: Proceedings of the International Symposium |date=2003 |publisher=The Electrochemical Society |isbn=978-1-56677-376-8 |pages=27–30}}{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=Springer Science & Business Media |isbn=9783540342588 |page=120}} Taking advantage of silicon dioxide's passivating effect on the silicon surface, Hoerni proposed to make transistors that were protected by a layer of silicon dioxide.{{cite book |last1=Lojek |first1=Bo |title=History of Semiconductor Engineering |date=2007 |publisher=Springer Science & Business Media |isbn=9783540342588 |page=120}} Later, Jean Hoerni, while working at Fairchild Semiconductor, had first patented the planar process in 1959.{{patent|US|3025589|Hoerni, J. A.: "Method of Manufacturing Semiconductor Devices” filed May 1, 1959}}{{patent|US|3064167|Hoerni, J. A.: "Semiconductor device" filed May 15, 1960}}