Andrea Urban and Dr. Franz Lärmer, two Bosch Group researchers, have been named European Inventors of the Year – an award sponsored by the EU Commission and the European Patent Office (EPO).
Urban and Dr. Lärmer developed a special plasma etching process for silicon, and it was only as a result of the process that it was possible to mass-produce MEMS sensors cost-effectively. The process, now known commonly as the “Bosch Process,” is now used to make nearly all MEMS. The process has more or less completely replaced other processes, such as the wet etching of silicon in potassium solution.
The basic patent on the technology dates back to 1992, and has been constantly further developed and refined since then. Today, there are roughly 40 patent families associated with the technology, and more than 350 individual patents have now been granted.
As a result of the plasma etching process, deep structures with vertical walls can be etched into silicon wafers with extreme precision and at high speed. Before this process, micro-structures could only be produced on a metal base using the expensive “LIGA” (lithography, electroplating, and moulding) process. For broad industrial applications, however, this process is far too complex and expensive.
One example of a sensor based on MEMS technology is the SMB 360, a triaxial acceleration sensor that has been developed specifically for consumer electronics. It can be used in areas such as entertainment electronics, mobile phones, and computer technology, but also in the areas of security and medicine. The sensor can for example trigger a radio alarm if someone falls or remains motionless on the ground, or if a notebook is removed without permission.
At the Bosch Reutlingen plant alone, more then 130 million sensors are produced every year using the Bosch Process.