AVS 62nd International Symposium & Exhibition | |
MEMS and NEMS | Wednesday Sessions |
Session MN+AM-WeA |
Session: | Emerging Materials & Fabrication Technologies toward Scalable & Additive Nanomanufacturing II |
Presenter: | Roya Maboudian, University of California at Berkeley |
Authors: | S. Chen, University of California at Berkeley L.E. Luna, University of California at Berkeley Z. You, Tsinghua University C. Carraro, University of California at Berkeley R. Maboudian, University of California at Berkeley |
Correspondent: | Click to Email |
Micro- and nano-electromechanical systems (M/NEMS) technology enables a diverse range of physical and chemical sensing under conditions close to ambient. However, there is a growing interest in sensors that can operate under harsh environments, including high temperature, high pressure, extreme radiation and corrosive. Sensing within these environments necessitates a robust semiconductor platform, different from those employed in traditional Si-based M/NEMS. A robust material, such as silicon carbide (SiC) provides compelling advantages not achievable with Si-based devices. SiC is a wide bandgap semiconductor with excellent mechanical, chemical and electrical stability, and thus is well suited for designing devices capable of operation in many harsh environments. Yet, harsh-environment stable metallization remains one of the key challenges with SiC technology. Here, we present a novel metallization scheme, utilizing solid-state graphitization of SiC, to improve the long-term reliability of Pt/Ti contacts to polycrystalline n-type SiC at high temperature. The metallization scheme includes an alumina protection layer and exhibits low stable contact resistivity even after long-term (500 hr) testing in air at 450 ºc. This study provides a feasible fabrication method and discusses the role of induced graphitic layer on contact stability.