The new CD lab produces more expensive semiconductor materials

Silicon semiconductors can only be used at relatively low voltages; Other materials, such as silicon carbide, are needed for higher currents. However, its production is very energy intensive and therefore the materials are very expensive. The Christian Doppler Laboratory (CD), which opened on Thursday at the Technical University (TU) in Vienna, now wants to make available solutions for the sustainable use of semiconductors by producing thin wafers from it.

Electronic components that can also control high currents are used in electric vehicle charging stations, in photovoltaic converters, or in wind power plants. “For voltages above 650 volts, silicon carbide is indeed the optimal material,” Georg Pfusterschmied of the Institute for Sensor and Actuator Systems at the Vienna University of Technology explained in a broadcast by the Christian Doppler Society (CDG). He heads the “New CD Laboratory for Sustainable Silicon Carbide Technology”.

However, silicon carbide has drawbacks: Wafers made of this material, which requires a lot of energy to produce, require a thickness of 350 to 500 micrometers “to ensure mechanical stability during manufacturing processes,” Pfusterschmied explained to APA. However, electronic components made from it often only need a fraction of this thickness, and much of the material is not used at all.

Making silicon carbide “smaller”.

The researchers at the new CD lab want to use a proprietary method to solve these problems with their business partners. Etching transforms silicon carbide into a porous structure in a precisely controlled manner so that a thin film can be separated. If this is then heated, a single, complete crystal is created with no holes again.

In this way, silicon carbide wafers can be produced with a thickness of only 20 microns, which is a quarter of the thickness of a human hair. By repeating this procedure, up to 20 thin sheets of silicon carbide wafer can be separated and used to fabricate components. “In the first pilot project, we were able to show that this process works on a small scale” on an industrial scale, says Pfusterschmied, who now wants to develop a basic understanding of the process as part of the CD Lab and support the company’s partners in scaling it up.

At CD Labs, which has been CDG-approved for seven years, scientists collaborate with companies on application-oriented basic research. Half of the budget comes from the public sector and commercial partners – in this particular case, the Upper Austria EV Group and the Belgian group Umicore.

service: https://www.cdg.ac.at/