Tantalum, required for high-performance micro-capacitors, is viewed in the microelectronics industry as a material which is difficult to substitute, and to date it has not been possible to recover it from end-of-life products. Particularly worrying are the facts that tantalum is illegally mined in certain Central African countries under degrading conditions, and the profits from its sale are used to finance civil wars.
Swiss companies also need to think closely about how they can reduce this dependency and avoid the possibility of delivery bottlenecks, remarked Jean-Philippe Kohl, the head of Swissmem's Economic Policy Group. A recent survey of the industry association's members in the Swiss mechanical engineering, electrical and metal sectors showed that every single company contacted used at least one of the critical raw materials. In order to protect themselves from possible shortages many of the companies had signed long-term delivery contracts with their suppliers. The others are cooperating with research institutions, either to develop alternative raw materials and technologies, or to optimize existing processes.
Alternatives from research labs
As an example of this approach, Stephan Buecheler explained how Empa's Thin-Films and Photovoltaic laboratory was working to reduce the thickness of the critical tellurium layer in flexible solar cells which use cadmium telluride (CdTe) as the active material. Similarly, efforts are being made in solar cells based on copper-indium-gallium-diselenide (CIGS) to replace the critical indium oxide with zinc oxide. In making these changes no loss of performance is expected. Quite the opposite, in fact the aim is to increase the efficiency of these devices by optimal use of raw materials and
|Contact: Dr. Patrick Wger|
Swiss Federal Laboratories for Materials Science and Technology (EMPA)