Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018)
    Biomaterial Surfaces & Interfaces Wednesday Sessions
       Session BI-WeE

Paper BI-WeE10
Synthesis and Characterization of Reactively Sputtered Platinum Group Metal Oxides for Stimulating and Recording Applications

Wednesday, December 5, 2018, 8:40 pm, Room Naupaka Salon 6-7

Session: Biomolecule/Material Interactions and Medical Applications
Presenter: Jeffrey Hettinger, Rowan University
Authors: G.V. Taylor, Rowan University
N. Page, Rowan University
A. Marti, Rowan University
R. Paladines, Rowan University
A. Fones, Johnson Matthey Inc., UK
S.D. Tint, Johnson Matthey Inc.
H. Hamilton, Johnson Matthey Inc., UK
S. Amini, Johnson Matthey Inc.
J.D. Hettinger, Rowan University
Correspondent: Click to Email
A range of materials have been examined as coatings over the past several decades to improve the performance of implantable devices used in neurostimulation and recording applications. Iridium oxide (IrO2) has been widely investigated due to its biocompatibility and high charge storage capacity. Modification of the synthesis conditions, as one means of improving the coating performance, led to reports of surface platelets forming at high deposition pressures. This study complements earlier research by extending the range of deposition parameters for the IrO2 system and investigates the ruthenium oxide (RuO2) system under the same experimental conditions. The results show that the platelet microstructure in tetragonal IrO2 is due to the formation of a specific orientation of crystallite. In contrast to previous reports that platelet formation coincided with a decrease in coating performance, it will be shown that the presence of platelets can improve the electrochemical performance of the coatings as measured by cyclic voltammetry in a phosphate buffered saline electrolyte. Furthermore, the platelet microstructure, and thereby the effective surface area, can be systematically controlled by adjusting deposition parameters, including temperature and oxygen partial pressure, used during the reactive sputtering. No such platelet formation has yet been observed in the RuO2 system.