Next Article in Journal
Correlation between Defect Density and Corrosion Parameter of Electrochemically Oxidized Aluminum
Previous Article in Journal
Response of Optically Transparent pH Sensing Films to Temperature and Temperature Variations
Open AccessArticle

Accelerated Hermeticity Testing of Biocompatible Moisture Barriers Used for the Encapsulation of Implantable Medical Devices

Centre for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 126, 9052 Gent, Belgium
*
Authors to whom correspondence should be addressed.
Coatings 2020, 10(1), 19; https://doi.org/10.3390/coatings10010019
Received: 28 November 2019 / Revised: 20 December 2019 / Accepted: 25 December 2019 / Published: 26 December 2019
Barrier layers for the long-term encapsulation of implantable medical devices play a crucial role in the devices’ performance and reliability. Typically, to understand the stability and predict the lifetime of barriers (therefore, the implantable devices), the device is subjected to accelerated testing at higher temperatures compared to its service parameters. Nevertheless, at high temperatures, reaction and degradation mechanisms might be different, resulting in false accelerated test results. In this study, the maximum valid temperatures for the accelerated testing of two barrier layers were investigated: atomic layer deposited (ALD) Al2O3 and stacked ALD HfO2/Al2O3/HfO2, hereinafter referred to as ALD-3. The in-house developed standard barrier performance test is based on continuous electrical resistance monitoring and microscopic inspection of Cu patterns covered with the barrier and immersed in phosphate buffered saline (PBS) at temperatures up to 95 °C. The results demonstrate the valid temperature window to perform temperature acceleration tests. In addition, the optimized ALD layer in combination with polyimide (polyimide/ALD-3/polyimide) works as effective barrier at 60 °C for 1215 days, suggesting the potential applicability to the encapsulation of long-term implants. View Full-Text
Keywords: temperature acceleration test; valid temperature window; moisture barrier; biocompatible encapsulation; ALD HfO2/Al2O3/HfO2; polyimide temperature acceleration test; valid temperature window; moisture barrier; biocompatible encapsulation; ALD HfO2/Al2O3/HfO2; polyimide
Show Figures

Graphical abstract

MDPI and ACS Style

Li, C.; Cauwe, M.; Mader, L.; Schaubroeck, D.; Op de Beeck, M. Accelerated Hermeticity Testing of Biocompatible Moisture Barriers Used for the Encapsulation of Implantable Medical Devices. Coatings 2020, 10, 19.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop