Fabrication and characterization of Pt Archimedean-spiral interdigitated microelectrodes with containing trenches

In this paper a Pt Archimedean-spiral interdigitated microelectrode with containing trenches was put forward, fabricated and characterized. Pt film with thickness 300nm was deposited by radio frequency (RF) magnetron sputtering on a Ti deposited n(100) Si substrate. On this Pt coated Si substrate a passivation layer of Si3N4 film with thickness 350nm was coated by plasma-enhanced chemical deposition (PECVD). The conventional photolithographic technique was used to pattern the Archimedean-spiral interdigitated microelectrodes with containing trenches, the contact tracks and the bond pads. Scanning electron microscopy (SEM) images along with filtration, line edge detection and fit operators of Mat-Lab software were employed to characterize the quality of Pt interdigitated microelectrodes. Cyclic voltammetry was performed on a CHI660D electrochemical workstation and the results indicated the critical dimension (CD) of Pt Archime-dean-spiral interdigitated microelectrode with containing trenches was within sub-micrometer range and the microelectrode can be used as the key sensing device in electrochemistry, biology, medicine and environmental monitoring.