John Robertson (physicist)

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John Robertson
Professor John Robertson FRS.jpg
John Robertson in 2015
Born1950 (age 7374) [1]
Alma mater University of Cambridge (BA, PhD)
Awards FRS (2015) [2]
Scientific career
Fields
Institutions
Thesis Electronic States in Amorphous Semi-Conductors  (1975)
Website eng.cam.ac.uk/profiles/jr214

John Robertson FRS [2] (born 1950) is a Professor of Electronics, in the Department of Engineering at the University of Cambridge. He is a leading specialist in the theory of amorphous carbon and related materials. [3] [4] [5]

Contents

Education

Robertson received his Bachelor of Arts and Doctor of Philosophy [6] degrees from the University of Cambridge. His PhD was awarded in 1975 for research on electronic states in amorphous semiconductors. [6]

Research and career

Following his PhD, Robertson worked at the Central Electricity Research Laboratories for 18 years,[ citation needed ] and in 1994 returned to Cambridge. He has published over 600 journal papers with around 33,000 citations. [3] His main topic of research is theory of carbon materials. [7] [8] [9] [10] [11] Other research interests include: carbon nanotubes, graphene, chemical vapour deposition, electronic applications (experimental and calculation); modelling of CVD mechanisms; carbon interconnects, carbon conductors, carbon for supercapacitors; high-κ dielectrics for complementary metal oxide semiconductor transistors; high-κ oxides on high mobility substrates such as InGaAs, Ge (modelling); transparent conducting oxides, amorphous oxide semiconductors (AOS) such as indium gallium zinc oxide, their thin film transistors, instability mechanisms (calculations); density functional calculations of semiconductors, oxides, carbon materials, and hybrid density functional calculations for correct band gaps; functional oxides, TiO2. [5] [4]

His research has been funded by the Engineering and Physical Sciences Research Council (EPSRC). [12]

Awards and honours

Robertson is a Fellow of the American Physical Society, the Institute of Electrical and Electronics Engineers (IEEE) and the Materials Research Society, and an Emeritus Editor of the journal Diamond and Related Materials. [13] He was elected a Fellow of the Royal Society (FRS) in 2015, [14] his certificate of election reads: "In recognition of his sustained contribution to the production and development of electronic devices". [2]

Related Research Articles

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A heterojunction is an interface between two layers or regions of dissimilar semiconductors. These semiconducting materials have unequal band gaps as opposed to a homojunction. It is often advantageous to engineer the electronic energy bands in many solid-state device applications, including semiconductor lasers, solar cells and transistors. The combination of multiple heterojunctions together in a device is called a heterostructure, although the two terms are commonly used interchangeably. The requirement that each material be a semiconductor with unequal band gaps is somewhat loose, especially on small length scales, where electronic properties depend on spatial properties. A more modern definition of heterojunction is the interface between any two solid-state materials, including crystalline and amorphous structures of metallic, insulating, fast ion conductor and semiconducting materials.

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Amorphous carbon is free, reactive carbon that has no crystalline structure. Amorphous carbon materials may be stabilized by terminating dangling-π bonds with hydrogen. As with other amorphous solids, some short-range order can be observed. Amorphous carbon is often abbreviated to aC for general amorphous carbon, aC:H or HAC for hydrogenated amorphous carbon, or to ta-C for tetrahedral amorphous carbon.

Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation.

<span class="mw-page-title-main">Organic field-effect transistor</span> Type of field-effect transistor

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<span class="mw-page-title-main">David Cockayne</span> British physicist

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<span class="mw-page-title-main">Hafnium(IV) oxide</span> Chemical compound

Hafnium(IV) oxide is the inorganic compound with the formula HfO
2
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<span class="mw-page-title-main">Indium(III) oxide</span> Chemical compound

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<span class="mw-page-title-main">Nicholas Harrison (physicist)</span>

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A carbon nanotube field-effect transistor (CNTFET) is a field-effect transistor that utilizes a single carbon nanotube (CNT) or an array of carbon nanotubes as the channel material, instead of bulk silicon, as in the traditional MOSFET structure. There have been major developments since CNTFETs were first demonstrated in 1998.

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<span class="mw-page-title-main">Andrea C. Ferrari</span> Italian scientist

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<span class="mw-page-title-main">Forouhi–Bloomer model</span> Popular optical dispersion relation

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References

  1. 1 2 3 "ROBERTSON, Prof. John" . Who's Who . Vol. 2016 (online Oxford University Press  ed.). Oxford: A & C Black.(Subscription or UK public library membership required.)
  2. 1 2 3 "Professor John Robertson FRS". London: The Royal Society. Archived from the original on 2 May 2015.
  3. 1 2 John Robertson's publications indexed by the Scopus bibliographic database. (subscription required)
  4. 1 2 "People in the Electronic Devices and Materials group". University of Cambridge. Archived from the original on 9 October 2014.
  5. 1 2 "Congratulations to Professors John Robertson and Zoubin Ghahramani on their elections as Fellows of the Royal Society". University of Cambridge. 13 May 2015. Archived from the original on 29 May 2015.
  6. 1 2 Robertson, John (1975). Electronic States in Amorphous Semi-Conductors (PhD thesis). University of Cambridge. OCLC   500550417.
  7. Ferrari, A.; Robertson, J. (2000). "Interpretation of Raman spectra of disordered and amorphous carbon". Physical Review B. 61 (20): 14095. Bibcode:2000PhRvB..6114095F. doi:10.1103/PhysRevB.61.14095.
  8. Robertson, J. (2002). "Diamond-like amorphous carbon". Materials Science and Engineering: R: Reports. 37 (4–6): 129–281. CiteSeerX   10.1.1.620.3187 . doi:10.1016/S0927-796X(02)00005-0. S2CID   135487365.
  9. Robertson, J. (2000). "Band offsets of wide-band-gap oxides and implications for future electronic devices". Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures. 18 (3): 1785–1791. Bibcode:2000JVSTB..18.1785R. doi:10.1116/1.591472.
  10. Robertson, J. (1986). "Amorphous carbon". Advances in Physics . 35 (4): 317–374. Bibcode:1986AdPhy..35..317R. doi:10.1080/00018738600101911.
  11. Robertson, J.; O'Reilly, E. (1987). "Electronic and atomic structure of amorphous carbon". Physical Review B. 35 (6): 2946–2957. Bibcode:1987PhRvB..35.2946R. doi:10.1103/PhysRevB.35.2946. PMID   9941778.
  12. "UK Government Research Grants awarded to John Robertson". Research Councils UK. Archived from the original on 29 May 2015.
  13. Diamond and Related Materials Editorial Board. journals.elsevier.com
  14. "Professor John Robertson FRS". London: Royal Society. Archived from the original on 17 November 2015.