TEM in situ test on micromechanical parts

The microstructural behaviour of mechanically loaded components from sensors or actuators has been investigated using transmission electron microscopy (TEM) in situ bending experiments. Therefore two different bending devices were developed. Samples were prepared from a silicon micromechanical pressure sensor and from a Si-wafer coated with different thin films. To achieve the required electron transparency in well defined areas, a modified cross section preparation technique was applied. Additionally to the observation of mechanically induced dynamical processes it is shown for the first time that silicon exhibits a slight plastic behaviour by dislocation emission from moving cleavage even at room temperature.