Influence of indenter angle on cracking in Si and Ge during nanoindentation

The influence of indenter angle on the nanoindentation cracking behavior of single crystal Si and Ge was systematically explored through nanoindentation experiments with a series of triangular pyramidal indenters with different centerline-to-face angles in the range 35.3–85.0°. The relationships between indentation load, crack length and indentation size and their dependence on indenter angle were carefully examined and compared with previous indentation cracking studies. The results are discussed in terms of ways to estimate fracture toughness and indentation cracking threshold loads more precisely through nanoindentation.