Abstract
Surfaces which can accurately distinguish spatial and temporal changes in temperature are critical for not only flow sensors, microbolometers, process control, but also future applications like electronic skins and soft robotics. Realizing such surfaces requires the deposition of thousands of thermal sensors over large areas, a task ideally suited for printing technologies. Negative temperature coefficient (NTC) ceramics represent the industry standard in temperature sensing due to their high thermal coefficient and excellent stability. A drawback is their complex and high temperature fabrication process and high stiffness, prohibiting their monolithic integration in large area or flexible applications. As a remedy, a printable NTC composite that combines a rapid and scalable all-printed fabrication process with performances that are on par with conventional NTC ceramics is demonstrated. The composite consists of micrometer-sized manganese spinel oxide particles dispersed in a benzocyclobutene matrix. The sensor has a B coefficient of 3500 K, with a 4.0% change in resistance at 25 °C, comparable to bulk ceramics. The selected polymer binder yields a composite exhibiting less than a 1 °C change in resistance to changes in humidity. The sensor's scalability is validated by demonstration of a A4-sized temperature sensing sheet consisting of over 400 sensors.
| Original language | English |
|---|---|
| Article number | 1800605 |
| Number of pages | 7 |
| Journal | Advanced Electronic Materials |
| Volume | 5 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Feb 2019 |
Funding
D.K. acknowledges the financial support of the Stavros Niarchos Foundation within the framework of the project ARCHERS. D.K. also acknowledges support by the project “Electronics Beyond Silicon Era” (ELBESIER) Erasmus+ KA2 program. This work was supported by funding from the European Union’s Horizon 2020 research and innovation program under grant agreement 731671. The authors thank Roy LeClerc (Signify) for assistance in preparation of the ceramic powder, Cees van der Marel and Harry Wondergem (Signify) for XPS and XRD analysis and modeling, Richard Janssen (Signify) for assistance on reliability measurements in the climate chamber, Jack Hoppenbrouwer (Philips Innovation Services) for obtaining SEM images. The authors also thank Dr. Daniele Raiteri (Holst Centre/TNO) for valuable discussions. A small error in the abstract and in the acknowledgements were corrected on February 8, 2019, after publication on early view.
Keywords
- ceramics
- organic–inorganic composites
- printed electronics
- temperature sensors