Hydrogen-induced delayed propagation of indentation crack in silicon single crystal

Stress corrosion crackings in humid air, hydrogen induced-cracking during dynamic charging in silicon single crystal have been investigated using sustained-load sample with indentation cracks. The possibility of hydrogen-induced delayed propagation induced by residual stress has been also studied using an unloaded indentation crack. The results show that there is no stress corrosion cracking in humid air at sustained load when the stress intensity factor ahead of the surface indentation crack is near to the fracture toughness K-IC, however, hydrogen-induced delayed propagation occurs during dynamic charging at sustained load with K-I=K-IC, and the normalized threshold stress intensity factor of crack arrest is K-IH/K-IC approximate to 0.9. Hydrogen-induced delayed propagation induced by the residual stress in an unloaded indentation crack can occur during charging, and the normalized threshold stress intensity factor K-IH/K-IC is also about 0.9.