Study of self-masking nanostructuring of boron doped diamond films by RF plasma etching

• Published in: Vacuum Vol. 170; p. 108954
• Main Authors: Marton, Marian, Ritomsky, Mario, Michniak, Pavol, Behul, Miroslav, Rehacek, Vlastimil, Redhammer, Robert, Vincze, Andrej, Papula, Martin, Vojs, Marian
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2019
• Subjects: Boron doped diamond; Nanostructured surface; Plasma etching; Self-masking; Self-masking; Boron doped diamond; Plasma etching; Nanostructured surface
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2019.108954

The surface nanostructuring of boron doped diamond (BDD) can further enhance its unique properties e.g. in electrochemical sensing, photoelectrochemical cells, field emission devices and various kinds of sensors. Here we present an investigation of plasmatic nanostructuring of BDD films without use of a time-consuming masking process. RF plasma technique was used to etch surface nanostructures with dimensions ranging from tenths to hundreds of nm in width and height. The size and shape of achieved diamond nanostructures were influenced only by applied etching parameters. We have found that the etched carbon is re-deposited in an amorphous form creating a mask and this self-masking process is responsible for the final shape of obtained structures. Therefore, this technique is effectively controllable by changing plasma power, gas type and pressure which influence the energy of incident ions and thus the sputtering yield and re-deposition of masking material. Utilization of various gas types, pressures and RF powers revealed the physical type of etching to be dominant over the chemical at both high and low energy ions. The nanostructured surfaces were then observed and characterized by SEM and Raman spectroscopy to investigate the nanostructures dimensions and to confirm the remaining diamond quality. [Display omitted] •RF plasma technique was used to etch BDD surface nanostructures with dimensions ranging from tenths to hundreds of nm.•The main reason for formation of nanostructures is the self-masking re-deposition of etched material from the diamond layer.•Ions with higher energy act more physically and etch the surface independently on the intergranular diamond structure.•Lower energy ions combine the physical and chemical part of etching promoting the formation of columnar like nanostructures.