Comparative Study on Metallization and Passivation Materials for High Temperature Sensor Applications

Abstract:

We investigated the performance of different metallization/passivation systems for high temperature applications. The metallizations comprised a 150 nm sputtered Pt or a 150 nm e-beam evaporated PtRh layer on Ti/TiN underlayers, respectively. The passivation coatings consisted of amorphous PECVD SiOx, of amorphous stress-reduced PECVD SiNy, and of a SiOx/ SiNy stack. For samples with SiOx and SiOx/ SiNy passivation layers the electrical properties changed after a short high temperature anneal at 600 °C but then remained stable during further annealing. This was attributed to the formation of PtTi alloys, which stabilized the metallization stack. In samples with SiNy passivation a significant Pt out-diffusion into the passivation layer was observed. This led to a degradation of the electrical and mechanical properties. The best performance was achieved with Pt-based metallizations and SiOx or SiOx/SiNy passivations.

• Periodical: Materials Science Forum (Volumes 679-680)
• Pages: 449-452
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.679-680.449
• Online since: March 2011
• Authors: Walter Daves, A. Krauss, Martin Le-Huu, S. Kronmüller, Volker Haeublein, Anton J. Bauer, Lothar Frey
• Keywords: High-Temperature, Metallization, Passivation, PECVD, Platinum, Platinum-Rhodium

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