Modern cars are full of sensors. The optimum quantity of air in the intake tract of a combustion engine is regulated by thermoelectric flow sensors, for instance.
They measure which quantities of a gas or a liquid flow in a particular direction. Another application for sensors like these is in medicine, where they regulate tiny quantities of drugs.
These thermoelectric sensors depend for their correct function on the right contact: The measuring sensors, consisting of a silicon wafer and a membrane, are embedded in a printed circuit board. So that the necessary current can flow between the contacts of the sensor and the printed circuit board, a conductor path has to be created – experts speak of ‘contacting’. Researchers at the Fraunhofer Institute for Manufacturing Engineering and Applied Materials Research IFAM in Bremen are working on a special technique: “Up to now, contacting was usually done with wire bonds – thin wires, that is,” explains IFAM project manager Christian Werner. “But wire bonds stick out, and thus impair the flow behavior of the gases and liquids.
That can affect high-precision measurements.” The researchers have therefore developed a new technique: INKtelligent printing®. What is different about this technique is that the researchers print the conductor paths instead of wiring them. This is basically a contactless aerosol printing method. The secret lies in the ink: “The suspension contains nano silver particles in a special solvent,” says Werner. “This enables us to print extremely thin-layered conductor paths.” Subsequent thermal treatment activates the electrical conductivity of the paths.
The researchers have tried and tested these conductor paths together with colleagues from the Institute for Microsensors, -actuators and -systems IMSAS in Bremen. Altogether, the engineers have solved one of the main problems of thermoelectric sensors. In contrast to wire bonds, which have an overall height of 1 to 1.5 millimeters, the printed conductor paths are a mere 2 to 3 micrometers high, or almost five hundred times thinner than wire bonds.
This enables the sensors to make far more accurate measurements. Fraunhofer researchers will be presenting the novel technology platform INKtelligent printing® at the Sensor and Test fair in Nuremberg from May 6 to 8 (Hall 7, Stand 331).
New materials: Growing polymer pelts
19.11.2018 | Karlsruher Institut für Technologie (KIT)
Why geckos can stick to walls
19.11.2018 | Jacobs University Bremen gGmbH
Max Planck researchers revel the nano-structure of molecular trains and the reason for smooth transport in cellular antennas.
Moving around, sensing the extracellular environment, and signaling to other cells are important for a cell to function properly. Responsible for those tasks...
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
19.11.2018 | Event News
09.11.2018 | Event News
06.11.2018 | Event News
20.11.2018 | Life Sciences
20.11.2018 | Life Sciences
20.11.2018 | Physics and Astronomy