Microfabrication and applications

The MNB group has been studying the fabrication and the properties of various new devices based on its expertise on CVD diamond deposition. With excellent biocompatibility and chemical stability, and a robust surface functionalization, diamond is an attractive material for bio-sensing applications. The group is developing different types of boron-doped diamond electrodes for water treatment [MNB08], CO2 reduction, transparent and conductive electrodes [MNB09], chemical and biological [MNB10] sensing, and neuro-signalling [MNB11]. In addition, to the electrochemical applications, the group is developing surface acoustic wave bio-sensors operating in liquids based on very thin diamond layers deposited on piezoelectric substrates (quartz, LiTaO3, etc.) at low temperature over large area. The development of electrochemical electrodes and sensors, and surface acoustic devices goes hand to hand with the development of microfabrication technologies. Hence, the group has been developing diamond’s microfabrication processes and methods for the development of these sensors and future electronic devices such as diamond diodes and field effect transistors.

Description

(upper left) Schematic and frequency response of diamond coated Love-wave surface acoustic wave sensors; (upper right) Diamond rotating ring-disk electrochemical electrodes; (middle left) Picture of hydrogenated nanocrystalline diamond based gas sensor; (centre) Schematic of gas sensor setup; (middle right) Dynamic sensing response curves of nanocrystalline diamond based response to NO2 gas; (bottom left) Electrochemical detection of dopamine using porous boron-doped diamond electrodes; (bottom centre) Scanning electron microscopy image of boron-doped diamond electronic test devices; (low right) Transparent and conductive boron-doped nanocrystalline diamond electrode on glass.

[MNB08] P. Ashcheulov et al., Nanocrystalline Boron-Doped Diamond as a Corrosion-Resistant Anode for Water Oxidation via Si Photoelectrodes, ACS Appl. Mater. Interfaces 10 (2018) 29552 - DOI: 10.1021/acsami.8b08714

[MNB09] P. Ashcheulov et al., Optically transparent composite diamond/Ti electrodes, Carbon 119 (2017) 179 - DOI: 10.1016/j.carbon.2017.04.035

 [MNB10] L .Drbohlavova et al., Love-wave devices with continuous and discrete nanocrystalline diamond coating for biosensing applications, Sens. Actuators, A 298 (2019) 111584 - DOI: 10.1016/j.sna.2019.111584

[MNB11] S. Baluchová, A. Taylor, V. Mortet et al, Porous boron doped diamond for dopamine sensing: Effect of boron doping level on morphology and electrochemical performance, Electrochim. Acta 327 (2019) 135025 - DOI: 10.1016/j.electacta.2019.135025