[Zurück]

S. Barth, L. Hrachowina, J. Sama, G. Domènech-Gil, J. Prades, A. Romano-Rodriquez, I. Gracia, C. Cane:
"Site-Specific Growth and In Situ Integration of Nanowires for Sensing Applications";
Vortrag: 2016 MRS Fall Meeting & Exhibit, Boston (eingeladen); 27.11.2016 - 02.12.2016; in: "2016 MRS Fall Meeting & Exhibit", (2016).

Nanostructured, porous oxides are prominent sensing materials due to the reversible change in resistivity upon changes in the surrounding atmosphere. Nanowires have gained considerable attention in gas sensing devices due to their high surface to volume ratio and high crystallinity. However, the cost effective integration of nanowires in functional devices is usually challenging and costly.
We present a cost effective and simple growth strategy using CMOS-compatible micromembranes containing a buried heating element, which is used for thermally induced chemical vapour growth of SnO2, WO3 and Ge. In addition, the buried heater can be used as the heating source for the effective operation as sensor. The small membrane volume and area requires low power (few mW) for both the growth and the operation of the resulting devices. The actual devices contain a porous network of nanowires bridging interdigitated electrodes on top of the membrane for the electrical readout. Secondary deposition products should be negligible, which can be demonstrated by cross-sectioning of the active part of the device. The devices have been successfully used in monitoring changes in CO [1], ammonia [2] and humidity [3] concentrations and show long-term stability. This contribution will address growth strategies and specific considerations for three different materials in regards to their applicability for sensor applications.