Insulation of thin-film parylene-C/platinum probes in saline solution through encapsulation in multilayer ALD ceramic films.
Biomed Microdevices
; 20(3): 61, 2018 07 26.
Article
em En
| MEDLINE
| ID: mdl-30051149
ABSTRACT
The long-term electrical leakage performance of parylene-C/platinum/parylene-C (Px/Pt/Px) interconnect in saline is evaluated using electrochemical impedance spectroscopy (EIS). Three kinds of additional ceramic encapsulation layers between the metal and Px are characterized 50 nm-thick alumina (Al2O3), 50 nm-thick titania (TiO2), and 80 nm-thick Al2O3-TiO2 nanolaminate (NL). The Al2O3 and TiO2 encapsulation layers worsen the overall insulation properties. The NL encapsulation layer improves the insulation when combined with a TiO2 outer layer to promote adhesion to the Px. Experiments are performed with various insulation promotion treatments A-174 silane (A174) treatment before Px deposition (to promote adhesion); SF6 plasma treatment (F) after Px deposition (to increase hydrophobicity); and ion-milling descum (IM) after Px deposition (to prevent parylene oxidation). A174 and F treatments do not have a significant impact, while IM leads to worse insulation performance. A circuit model elucidates the insulation characteristics of Px-ceramic-Pt-ceramic-Px interconnect. These studies provide a foundation for processing ultra-compliant neural probes with long-term chronic utility.
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Base de dados:
MEDLINE
Assunto principal:
Platina
/
Polímeros
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Xilenos
/
Cerâmica
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article