The influences of sharp notches on the strength of silicon components

V-notches, which may frequently occur in micromechanical components made of single-crystalline silicon due to the manufacturing process, may be the failure focus under mechanical loading. The failure can be predicted by comparing the notch tip stress intensity factor A(1) with the notch toughness A(1C). By means of the experimentally determined notch toughness values the V-notched silicon structural components can be designed, which is demonstrated for an acceleration sensor. The influence of an isotropic etching process which leads to round notches on the strength of the components is discussed.