Beams

Beams are an important mechanical basic element in microtechnique. They are the microscopic correspondence to macroscopic bearings and springs. They can be made of nearly every rigid material such as silicon, oxides, nitrides, glasses, polymers, and metals. Their thickness typically is in the range of 1–500 μm. Beams which are thinner than 1 μm are very hard to manufacture and are not strong enough, in general. The upper limit is given by the fact that thicker beams are no longer a microscopic element. The width of beams is not much smaller than their thickness but may become a factor of 100 larger than it. When it is bent transversally, the dimension of the beam in the direction of bending is called its thickness and the dimensions perpendicular to this are called width and length. The length of beams typically is in the range between 10 μm and 20 mm. Again the lower limit is defined by the possibilities of fabrication, while the upper limit is approximately the limit to the macroscopic world. However, all equations discussed here are valid in the macroscopic world also.