Fracture in Hydrogen‐Implanted Germanium

We have studied the mechanism of fracture in hydrogen‐implanted Ge. First, the as‐implanted Ge state and its evolution during subsequent annealing were characterized via TEM and FTIR‐MIR spectroscopy. Results showed that the extended defects formation and growth follow the same basic mechanism in Ge as in Si, which is the reference material. Nevertheless, the global damage level in the implanted Ge layer is higher compared to Si. Second, the fracture step was studied via the fracture kinetics analysis, SIMS and AFM on the transferred layer. An activation energy comparable to the reported data from blistering studies was obtained. Just like in Si, the Cmax of H in Ge measured via SIMS was found to decrease during the fracture anneal. This decrease is associated with the formation of gaseous H2 that pressurizes the internal cavities and then contributes to the fracture. Finally, a high roughness of the Ge transferred layer was measured, which results from the large thickness of the implantation damaged zone.