Category: 2021

Review of 2020

Happy New Year

2020 will forever be the year of viruses for me and a lot of us. At Maastricht University, the year started with a university wide cyber-attack with ransomware. After the computer-viruses came the human viruses, with COVID-19 shutting down one country after the other, and shutting down education systems as well.

Hopefully 2021 will be better behaved, though we know already some of the hurdles which will make life interesting the coming year. COVID-19 is far from over, and it will take at least a year to vaccinate everyone. Furthermore, as of the first of today, the United Kingdom is no longer a part of the EU, making travel inside Europe a little harder again.

But before we launch into these new and interesting times, lets look back at 2020 one last time, keeping up with  tradition. What have I done during the last year of academic merit.

1. Publications: +6 (and currently a handful in progress)

2. Completed refereeing tasks: +17

  • Applied Physics Letters
  • Journal of Physical Chemistry (2x)
  • Computational Materials Science (2x)
  • Materials Chemistry and Physics
  • Journal of Physics: Condensed Matter (5x)
  • Diamond and Related Materials (6x)

3. Conferences & workshops in times of Corona: +3/+1 (Attended & Organised), >+4 internal 

ACOS poster prize 2020

ACOS poster prize 2020

With regard to conferences, 2020 was the year everyone came into contact with the concept of the online conference. Many conferences and events got canceled: such as TEDx@UHasselt (which will return in 2021)

  • ACOS 2020, Online, Oktober 28th, 2020 [poster presentation and video-pitch, 2nd poster prize]
  • RSC Chemical Science Symposium 2020, Online, September 29th-30th, 2020 [iposter presentation]
  • D-NL-HIT project meetings [oral presentations]
    • Virtual Partner Meeting, April 8th, 2020
    • Adhesives Pilot Branch meeting, October 7th, 2020
    • Virtual Partner Meeting, October 15th, 2020
    • UV-Curing Branch meeting, October 22nd, 2020
  • SBDD XXV, Hasselt University, Belgium, March 11th-13th, 2020 [(invited) oral presentation, poster presentation] …On Friday13th Belgium went into it’s first lock-down.
  • Pilot Branch meeting adhesives D-NL-HIT project, Maastricht University, Brighlands campus, February 26th, 2020 [Organised]

4. Science Communication & Social media:   

  • In February 2020, I finally caved and joined Twitter as @DelocalizedD .
  • Added several new repositories to my github account, with the most important ones being:
  • Started a YouTube channel (for the ACOS video pitch)

5. Current size of HIVE:

  • Continued work on a public version of HIVE at github: HIVE 4.x   (26K lines, 9 commands available)
  • 61K lines of program (code: 69 %)
  • ~100 files
  • 49 (command line) options

6. Hive-STM program:

And now, upward and onward, a new year, a fresh start.

Impact of methane concentration on surface morphology and boron incorporation of heavily boron-doped single crystal diamond layers

Authors:  Rozita Rouzbahani, Shannon S.Nicley, Danny E.P.Vanpoucke, Fernando Lloret, Paulius Pobedinskas, Daniel Araujo, Ken Haenen
Journal: Carbon 172, 463-473 (2021)
doi: 10.1016/j.carbon.2020.10.061
IF(2019): 8.821
export: bibtex
pdf: <Carbon>

 

Graphical Abstract B doped diamond
Graphical Abstract: Artist impression of B incorporation during CVD growth of diamond.

Abstract

The methane concentration dependence of the plasma gas phase on surface morphology and boron incorporation in single crystal, boron-doped diamond deposition is experimentally and computationally investigated. Starting at 1%, an increase of the methane concentration results in an observable increase of the B-doping level up to 1.7×1021 cm−3, while the hole Hall carrier mobility decreases to 0.7±0.2 cm2 V−1 s−1. For B-doped SCD films grown at 1%, 2%, and 3% [CH4]/[H2], the electrical conductivity and mobility show no temperature-dependent behavior due to the metallic-like conduction mechanism occurring beyond the Mott transition. First principles calculations are used to investigate the origin of the increased boron incorporation. While the increased formation of growth centers directly related to the methane concentration does not significantly change the adsorption energy of boron at nearby sites, they dramatically increase the formation of missing H defects acting as preferential boron incorporation sites, indirectly increasing the boron incorporation. This not only indicates that the optimized methane concentration possesses a large potential for controlling the boron concentration levels in the diamond, but also enables optimization of the growth morphology. The calculations provide a route to understand impurity incorporation in diamond on a general level, of great importance for color center formation.