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The international standard ISO 6336-3 defines a calculation method for the tooth root capacity of standard gears with basic rack profile according to ISO 53. However, the results of this method may become too optimistic for non-standard gears with custom root fillets, large pressure angles or asymmetric teeth, since the effect of general mean stresses on the local tooth root strength are neglected. Therefore, a more generic calculation method is suggested, which considers the mean stress influence by utilizing the Haigh diagram. Both approaches are then used as basis of root fillet shape optimizations. A comparison of results demonstrates significant differences in the safety assessment and the resulting root geometry.
Compositional characterization of interfaces in Si-cap/SixGe1-x/Si heterostructures is an important topic in SiGe based advanced microelectronics and in quantum wells. Extremely high depth resolution is required to detect and optimize near-interface compositional gradients which are crucial for high circuit performance. We report on non-destructive, high-resolution, near-interface depth profiling using SR photoelectron spectroscopy at an undulator beamline. We measured the Ge content at the SixGe1-x interface towards the native SiO2 layer and investigated the influence of additional (1nm and 2nm) Si capping layers (Si-cap). For the uncapped samples we found near the oxide/ SiGe interface region a strong mixing of Ge-oxides and SiOx. This indicates a high instability of the Ge atoms at those interfaces while silicon capped (1nm, 2nm) SixGe1-x films are more stable. We detect sharp Ge concentration gradients within the first 1nm at the Si/SixGe1-x interface. These results open new possibilities for Ge profile optimization in Si-cap/SixGe1-x/Si heterostructures. In the Ge3d spectra we differentiate the Ge atoms to occupy three different lattice sites and are able to follow their relative occupation within the Ge gradient.