... technology 'made in Germany' was also used: the design and electronics of the high-tech camera installed in Rosetta come from Tecnotron in Weißensberg. The particular challenge in developing the circuit boards for the camera was mounting the 15 x 30 mm unhoused CCD chip. The different thermal expansion coefficients of the chip and the conventional circuit board would have generated too much mechanical stress on Mars, which would have destroyed the sensor. Only by using a very special multilayer composite structure made of polyimide and molybdenum and an additional compensation surface made of Invar between the PCB surface and the CCD chip was it possible to shift the mechanical stress to the 'inside' of the PCB - away from the CCD sensor.