Fully Inkjet-Printed Flexible Wheatstone Bridge Temperature Sensors (Printed Electronics Europe 2015)

We present a fully inkjet-printed flexible Wheatstone bridge used for temperature sensing. For this purpose, we used a carbon nanoparticle ink as PTC-material (positive temperature coefficient) and a mixture of poly(3,4-ethylenedioxythophene):poly(4-styrenesulfonate) (PEDOT:PSS) with dimethyl sulfoxide (DMSO) as NTC-material (negative temperature coefficient). We evaluated different ink compositions in order to optimize the temperature coefficient of resistance (TCR), the stability and the reliability of the used materials. The Wheatstone bridge sensors show good linearity and little hysteresis within a temperature range of 20°C to 70°C.

Siemens AG, Corporate Technology, Research and Technology Center, Munich, Germany

 Institute for Print and Media Technology of Chemnitz University of Technology (pmTUC), Chemnitz, Germany

 PhD thesis: "Use of the coffee ring effect for the realization of all-inkjet printed organic field effect transistors with small channel length"

Siemens AG (Berlin and Munich) is a global technology powerhouse that has stood for engineering excellence, innovation, quality, reliability and internationality for more than 170 years. The company is active around the globe, focusing on the areas of electrification, automation and digitalization. One of the largest producers of energy-efficient, resource-saving technologies, Siemens is a leading supplier of efficient power generation and power transmission solutions and a pioneer in infrastructure solutions as well as automation, drive and software solutions for industry. With its publicly listed subsidiary Siemens Healthineers AG, the company is also a leading provider of medical imaging equipment - such as computed tomography and magnetic resonance imaging systems - and a leader in laboratory diagnostics as well as clinical IT. In fiscal 2018, which ended on September 30, 2018, Siemens generated revenue of €83.0 billion and net income of €6.1 billion. At the end of September 2018, the company had around 379,000 employees worldwide. Further information is available on the Internet at www.siemens.com .