Peter Trefonas

{{Infobox scientist | name = Peter Trefonas | image = | birth_date = {{birth year and age|1958}} | birth_place = Minneapolis, Minnesota, U.S. | death_date = | death_place = | field = Lithography | work_institutions = Dow Chemical | alma_mater = University of New Orleans, University of Wisconsin-Madison | doctoral_advisor = Robert West | awards = ACS Heroes of Chemistry <small>2014</small>, Perkin Medal <small>2016</small> | spouse = }}

{{external media | width = 210px | float = right | headerimage= | video1 = [http://www.spie.org/newsroom/trefonas-video "Peter Trefonas: Chemistry is key player in lithography process"], Micro/Nano Lithography, SPIE | video2 = [https://www.acs.org/content/acs/en/funding-and-awards/awards/industry/heroes/2014-heroes-of-chemistry-Dow-Chemical.html "Dow Chemical - Dow AR Fast Etch Organic Bottom Antireflectant Coatings"], ACS }}

'''Peter Trefonas''' (born 1958) is a retired DuPont Fellow (a senior scientist) at DuPont, where he had worked on the development of electronic materials. He is known for innovations in the chemistry of photolithography, particularly the development of anti-reflective coatings and polymer photoresists that are used to create circuitry for computer chips. This work has supported the patterning of smaller features during the lithographic process, increasing miniaturization and microprocessor speed.<ref name="Reisch"/><ref name="SCI">{{cite web|title=Perkin Medal|url=http://sci-america.org/site/?page_id=68|website=SCI|access-date=12 April 2017}}</ref>

==Education== Peter Trefonas is a son of Louis Marco Trefonas, also a chemist, and Gail Thames.<ref name="Sentinel">{{cite web|title=Dr. Louis Marco Trefonas|url=http://www.legacy.com/obituaries/orlandosentinel/obituary.aspx?pid=17008406|website=Orlando Sentinel|access-date=20 April 2017}}</ref> He was inspired by ''Star Trek'' and the writings of Isaac Asimov, and created his own chemistry lab at home.<ref name="Reisch"/> Trefonas attended the University of New Orleans, receiving his Bachelor of Science in chemistry in 1980.<ref name="Perkin"/>

While an undergraduate, Trefonas earned money by writing video games for early personal computers. These included ''Worm'', a clone of the 1976 arcade video game ''Blockade'', and a clone of the arcade game ''Hustle'' (1977), which itself was based on ''Blockcade''. ''Worm'' was the first of what would become many games in the snake video game genre for home computers.<ref name="Goggin">{{citation|title=Global Mobile Media|author=Gerard Goggin|publisher=Taylor & Francis|year=2010|isbn=978-0-415-46917-3|page=101|url=https://books.google.com/books?id=cellOt5myTsC&pg=PA101|access-date=2011-04-07}}</ref><ref>{{cite web|title=Retro Corner: 'Snake'|url=http://www.digitalspy.com/gaming/retro-gaming/news/a313438/retro-corner-snake/|website=Digital Spy|access-date=12 April 2017|date=2011-04-09}}</ref> Trefonas also wrote a game based on ''Dungeons & Dragons''.<ref>{{cite web|title=CLOAD Magazine|url=http://www.gametronik.com/site/rubriques/tandy/FAQs/CLOAD%20Magazine%201980-05%20(1980)(CLOAD%20Magazine%20Inc).pdf|archive-url=https://web.archive.org/web/20110719015431/http://www.gametronik.com/site/rubriques/tandy/FAQs/CLOAD%20Magazine%201980-05%20(1980)(CLOAD%20Magazine%20Inc).pdf|url-status=usurped|archive-date=July 19, 2011|website=Gametronik|date=May 1980}}</ref>

Trefonas studied at the University of Wisconsin-Madison with Robert West,<ref name="Perkin"/> completing a Ph.D. in inorganic chemistry in late 1984.<ref name="Reisch"/> Trefonas became interested in electronic materials after working with West and chip makers from IBM to create organosilicon bilayer photoresists.<ref name="Reisch"/> His thesis topic was "Synthesis, properties and chemistry of organosilane and organogermane high polymers" (1985).<ref name="Madison">{{cite book|last1=Trefonas|first1=Peter|title=Synthesis, properties and chemistry of organosilane and organogermane high polymers|url=https://search.library.wisc.edu/catalog/999560446602121|access-date=11 April 2017|publisher=[publisher not identified]|year=1985}}</ref>

==Career== Trefonas joined MEMC Electronic Materials in late 1984. In 1986, he and others co-founded Aspect Systems Inc., utilizing photolithography technology acquired from MEMC.<ref name="Reisch"/> Trefonas worked at Aspect from 1986-1989. Then, through a succession of company acquisitions, he moved to Shipley Company (1990-2000), Rohm and Haas (1997-2008), to The Dow Chemical Company (2008-2019), and finally to DuPont (2019-current).<ref name="Alumni">{{cite web|title=Alumni: Peter Trefonas|url=http://alumnius.net/university_of_new_or-8446-128|website=University of New Orleans|access-date=12 April 2017}}</ref><ref name="Rocha">{{cite news|last1=Rocha|first1=Euan|last2=Daily|first2=Matt|title=Dow Chemical to buy Rohm and Haas for $15.3 bln|url=https://www.reuters.com/article/us-rohmandhaas-dowchemical-idUSWNAB026420080710|access-date=12 April 2017|work=Reuters|date=July 10, 2008}}</ref><ref name="Campoy">{{cite news|last1=Campoy|first1=Ana|title=Dow Chemical Closes Rohm & Haas Deal|url=https://www.wsj.com/articles/SB123860746676278981|access-date=20 April 2017|work=The Wall Street Journal|date=April 2, 2009}}</ref><ref name="Reisch">{{cite journal|last1=Reisch|first1=Marc S.|title=C&EN talks with Peter Trefonas, photolithography innovator|journal=Chemical & Engineering News|date=September 12, 2016|volume=94|issue=36|pages=27–28|url=http://cen.acs.org/articles/94/i36/CEN-talks-Peter-Trefonas-photolithography.html|quote="Note Correction, published in October: 'Sept. 12, page 27: A feature story profiling Dow Chemical's Peter Trefonas incorrectly identified when Dow acquired Rohm and Haas. The acquisition occurred in 2009, not 2001.'"}}</ref>

Trefonas has published at least 137 journal articles and technical publications. He has received 132 US patents.<ref name="SPIE"/><ref name="CP"/>

==Research== Throughout his career, Trefonas has focused on materials science and the chemistry of photolithography. By understanding the chemistry of photoresists used in lithography, he has been able to develop anti-reflective coatings and polymer photoresists that support finely-tuned etching used in the production of integrated circuits. These materials and techniques make it possible to fit more circuits into a given area.<ref name="CP"/><ref name="SCI"/> Over time, lithographic technologies have developed to allow lithography to use smaller wavelengths of light. Trefonas has helped to overcome a number of apparent limits to the sizes that are achievable, developing photoresists that are responsive to 436-nm and 365-nm ultraviolet light, and as small as 193 nm deep.<ref name="Effect"/><ref name="Blacksmith">{{cite journal|last1=Trefonas III|first1=Peter|last2=Blacksmith|first2=Robert F.|last3=Szmanda|first3=Charles R.|last4=Kavanagh|first4=Robert J.|last5=Adams|first5=Timothy G.|title=Organic antireflective coatings for 193-nm lithography|journal=Proc. SPIE 3678, Advances in Resist Technology and Processing|date=June 11, 1999|volume=XVI|issue=702|page=702|doi=10.1117/12.350257|series=Advances in Resist Technology and Processing XVI|bibcode=1999SPIE.3678..702T |s2cid=138376696 }}</ref>

In 1989, Trefonas and others at Aspect Systems Inc. reported on extensive studies of polyfunctional photosensitive groups in positive photoresists. They studied diazonaphthoquinone (DNQ), a chemical compound used for dissolution inhibition of novolak resin in photomask creation. They mathematically modeled effects, predicted possible optimizations, and experimentally verified their predictions. They found that chemically bonding together three of the molecules of DNQ to create a new molecule containing three dissolution inhibitors in a single molecule, led to a better feature contrast, with better resolution and miniaturization.<ref name="US5128230A">{{cite patent | country = US | number = 5128230 A | status =  | title = Quinone diazide containing photoresist composition utilizing mixed solvent of ethyl lactate, anisole and amyl acetate | pubdate = July 7, 1992 | gdate =  | fdate =  | pridate =  | inventor = | invent1 = Michael K. Templeton | invent2 = Anthony Zampini | invent3 = Peter Trefonas III | invent4 = James C. Woodbrey, David C. Madoux, Brian K. Daniels | assign1 = Shipley Company Inc. | class =  | url = https://www.google.com/patents/US5128230 }}</ref> These modified DNQs became known as "polyfunctional photoactive components" (PACs). This approach, which they termed polyphotolysis,<ref name="Levy">{{cite book|last1=Levy|first1=R. A.|title=Microelectronic materials and processes: [proceedings of the NATO Advanced Study Institute on Microelectronic Materials and Processes, Il Ciocco, Castelvecchio Pascoli, Italy, June 30-July 11, 1986]|date=1989|publisher=Kluwer Academic|location=Dordrecht|isbn=978-0-7923-0147-9|pages=333–334|url=https://books.google.com/books?id=A4tqCQAAQBAJ&pg=PA333|access-date=12 April 2017}}</ref><ref name="Suzuki">{{cite book|last1=Suzuki|first1=Kazuaki|last2=Smith|first2=Bruce W.|title=Microlithography science and technology|date=2007|publisher=CRC Press|location=Boca Raton|isbn=978-0-8247-9024-0|page=130|edition=2nd|url=https://books.google.com/books?id=_hTLDCeIYxoC&pg=PA130|access-date=13 April 2017}}</ref> <ref name="Daniels">{{cite journal|last1=Trefonas III|first1=P.|last2=Daniels|first2=B. K.|title=New Principle for Image Enhancement in Single Layer Positive Photoresists|journal=SPIE Advances in Resist Technology and Processing|date=August 25, 1987|volume=IV|issue=771|pages=194–210|doi=10.1117/12.940326 |bibcode=1987SPIE..771..194T |s2cid=96668019 |url=http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1247418|url-access=subscription}}</ref> has also been referred to as the "Trefonas Effect."<ref name="Effect">{{cite web|title=Peter Trefonas, 2016 Perkin Medal Recipient, Credits Chemistry for Enabling the Information Age|url=http://blog.dowelectronicmaterials.com/en/posts/2016/09/peter-trefonas-2016-perkin-medal-recipient-credits-chemistry-for-enabling-the-information-age|archive-url=https://web.archive.org/web/20170624001855/http://blog.dowelectronicmaterials.com/en/posts/2016/09/peter-trefonas-2016-perkin-medal-recipient-credits-chemistry-for-enabling-the-information-age|url-status=usurped|archive-date=June 24, 2017|website=DOW Electronic Materials|access-date=September 26, 2016}}</ref><ref name="Han">{{cite journal|last1=Han|first1=Yu-Kai|last2=Yan|first2=Zhenglin|last3=Reiser|first3=Arnost|title=Mechanism of the Trefonas Effect (Polyphotolysis) in Novolak−Diazonaphthoquinone Resists|journal=Macromolecules|date=December 1999|volume=32|issue=25|pages=8421–8426|doi=10.1021/ma990686j|bibcode=1999MaMol..32.8421H }}</ref> The technology of trifunctional diazonaphthoquinone PACs has become the industry standard in positive photoresists.<ref name="Han"/> Their mechanism has been elucidated and relates to a cooperative behavior of each of the three DNQ units in the new trifunctional dissolution inhibitor molecule. Phenolic strings from the acceptor groups of PACs that are severed from their anchors may reconnect to living strings, replacing two shorter polarized strings with one longer polarized string.<ref name="Reiser">{{cite book|last1=Han|first1=Yu-Kai|last2=Reiser|first2=Arnost|chapter=Mechanism of the Trefonas effect (Polyphotolysis) in dissolution inhibition resists |editor-first1=Will |editor-last1=Conley |title=Advances in Resist Technology and Processing XVI|journal=SPIE Proceedings: Advances in Resist Technology and Processing XVI|date=June 11, 1999|volume=3678|page=360|doi=10.1117/12.350219|chapter-url=http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=983915|access-date=30 May 2017|bibcode=1999SPIE.3678..360H |s2cid=95748950 }}</ref>

Trefonas has also been a leader in the development of fast etch organic Bottom Antireflective Coating (BARC)<ref name="Heroes"/> BARC technology minimizes the reflection of light from the substrate when imaging the photoresist. Light that is used to form the latent image in the photoresist film can reflect back from the substrate and compromise feature contrast and profile shape. Controlling interference from reflected light results in the formation of a sharper pattern with less variability and a larger process window.<ref name="Cameron">{{cite news|last1=Cameron|first1=Jim|title=Litho University: DBARC Technology 101|url=http://blog.dowelectronicmaterials.com/en/posts/2015/11/litho-university-dbarc-technology-101|archive-url=https://web.archive.org/web/20160829030100/http://blog.dowelectronicmaterials.com/en/posts/2015/11/litho-university-dbarc-technology-101|url-status=usurped|archive-date=August 29, 2016|access-date=30 May 2017|work=Dow Electronic Materials|date=November 18, 2015}}</ref>

In 2014, Trefonas and others at Dow were named Heroes of Chemistry by the American Chemical Society, for the development of Fast Etch Organic Bottom Antireflective Coatings (BARCs).<ref name="Heroes" /> In 2016, Trefonas was recognized with The SCI Perkin Medal for outstanding contributions to industrial chemistry. In 2018, Trefonas was named as a Fellow of the SPIE for "achievements in design for manufacturing & compact modeling." Peter Trefonas was elected to the National Academy of Engineering in 2018 for the "invention of photoresist materials and microlithography methods underpinning multiple generations of microelectronics". DuPont Company in 2019 recognized Trefonas with its top recognition, the Lavoisier Medal, for "commercialized electronic chemicals which enabled customers to manufacture integrated circuits with higher density and faster speeds".

==Awards and honors== * 2022, "Industry Project Award" of the Institution of Chemical Engineers (IChemE) * 2021, ACS Carothers Award * 2019, DuPont Company Lavoisier Medal * 2018, elected to the National Academy of Engineering<ref>{{Cite web|url=https://www.nae.edu/178117.aspx|title=National Academy of Engineering Elects 83 Members and 16 Foreign Members|website=NAE Website|access-date=2018-02-17}}</ref> * 2018, named Fellow of the SPIE<ref>{{Cite web|url=http://spie.org/about-spie/fellows-and-senior-members/fellows|title=2017 SPIE Fellows|website=spie.org|access-date=2018-02-17}}</ref> * 2016, Perkin Medal, from the Society of Chemical Industry<ref name="CP">{{cite news|title=SCI Awards Perkin Medal To Dow's Peter Trefonas By Chemical Processing Staff|url=http://www.chemicalprocessing.com/industrynews/2016/sci-awards-perkin-medal-to-dows-peter-trefonas/|access-date=12 April 2017|work=Chemical Processing|date=May 10, 2016}}</ref><ref name="Perkin">{{cite web|title=SCI Perkin Medal|url=https://www.sciencehistory.org/sci-perkin-medal|website=Science History Institute|access-date=24 March 2018|date=2016-05-31}}</ref> * 2014, ACS Heroes of Chemistry, from the American Chemical Society (one of thirteen scientists from the Dow Chemical Company credited with the development of Dow AR Fast Etch Organic Bottom Antireflectant Coatings)<ref name="Heroes">{{cite web|title=2014 Heroes of Chemistry|url=https://www.acs.org/content/acs/en/funding-and-awards/awards/industry/heroes/2014-heroes-of-chemistry-Dow-Chemical.html|website=ACS Chemistry for Life|access-date=12 April 2017}}</ref> * 2013, SPIE C. Grant Willson Best Paper Award in Patterning Materials and Processes<ref name="SPIE">{{cite journal|last1=SPIE|title=Peter Trefonas: Chemistry is key player in lithography process|journal=SPIE Newsroom|date=22 August 2016|doi=10.1117/2.201608.02|url=http://www.spie.org/newsroom/trefonas-video|url-access=subscription}}</ref> jointly with researchers at Dow and Texas A&M University,<ref name="Joint">{{cite web|title=Dow Electronic Materials and Texas A&M University Win SPIE's 2013 Willson Award for Best Technical Paper|url=http://www.dowelectronicmaterials.com/news/2014/20140320a.htm|archive-url=https://web.archive.org/web/20150307034527/http://www.dowelectronicmaterials.com/news/2014/20140320a.htm|url-status=usurped|archive-date=March 7, 2015|website=Dow Electronic Materials News|access-date=March 20, 2014}}</ref> from SPIE for the paper "Bottom-up / top-down high-resolution, high-throughput lithography using vertically assembled block brush polymers".<ref name="Bottom">{{cite journal|last1=Trefonas|first1=Peter|last2=Thackeray|first2=James W.|last3=Sun|first3=Guorong|last4=Cho|first4=Sangho|last5=Clark|first5=Corrie|last6=Verkhoturov|first6=Stanislav V.|last7=Eller|first7=Michael J.|last8=Li|first8=Ang|last9=Pavia-Sanders|first9=Adriana|last10=Schweikert|first10=Emile A.|last11=Wooley|first11=Karen L.|title=Bottom-up/top-down, high-resolution, high-throughput lithography using vertically assembled block bottle brush polymers|journal=Journal of Micro/Nanolithography, MEMS, and MOEMS|date=16 December 2013|volume=12|issue=4|article-number=043006|doi=10.1117/1.JMM.12.4.043006|bibcode=2013JMM&M..12d3006T |s2cid=123535313 |url=http://nanolithography.spiedigitallibrary.org/article.aspx?articleid=1790737|access-date=12 April 2017|url-access=subscription}}</ref>

==References== {{reflist}}

{{DEFAULTSORT:Trefonas, Peter}} Category:1958 births Category:Living people Category:American physical chemists Category:Inorganic chemists Category:Photochemists Category:Polymer scientists and engineers Category:Chemists from Louisiana Category:Scientists from New Orleans Category:20th-century American chemists Category:21st-century American chemists Category:University of New Orleans alumni Category:University of Wisconsin–Madison College of Letters and Science alumni Category:Chemists from Minnesota