In Si and Ge, H-implantation induced blistering is a complex phenomenon involving various mechanisms, from the nucleation and growth of gas-vacancies complexes, at the nanometer scale, to the mechanical buckling of the materials at the microscopic scale. The pressure due to the diffusion and absorption of H in the cavities during post-implantation thermal treatments has been identified as a relevant parameter to understand the blistering phenomenon. Analytical models based on the elastic theory of thin plates have been proposed to evidence its influence on buckling and recently, finite element simulations have allowed to derive the amount of gas accumulated in the cavities on implanted W. However, a number of issues still remain unexplored, among which is the effect of the internal stress on blistering.

We explore the coupling effect on blistering between the pressure in the cavities and the internal stress in H-implanted Si and Ge (001) wafers. An analytical model based on the Föppl-von Karman elastic theory of thin plates is developed to determine the pressure in the cavity as a function of the internal stress in the implanted layer. This model is then combined to experimental observations. Si and Ge samples are implanted with H at high fluence and the internal stress is measured by the classic curvature method. The samples are then annealed at low thermal budget leading to the formation of blisters distributed all over the material surface. The morphology of the blisters is characterized by atomic force microscopy. The internal pressure in the cavities is then estimated for several blisters in both materials and the mechanical behaviour of Si and Ge with respect to H-implantation is compared.