Thermal evolution of surface blistering and exfoliation due to ion-implanted hydrogen monomers into Si < 1 1 1>

This study investigated the dependence of surface blistering and exfoliation phenomena on post-annealing time in H+-implanted Si. Czochralski-grown n-type Si wafers were room-temperature ion-implanted with 40 keV hydrogen monomers to a fluence of 5x10 super(16) cm super(-2), and followed by furnace annealing treatments at 400 and 500 [deg]C for various durations ranging from 0.25 to 3 h. The corresponding analysis results for Si [1] (Liang et al., 2008); [2] (Bai, 2007) were adopted in order to make comparisons. The evolution of blister formation and growth for Si at 400 [deg]C has a shorter characteristic time compared to Si. However, there is a longer characteristic time when annealing takes place at 500 [deg]C. In addition, no craters were observed for Si annealed at 400 [deg]C while the opposite is true for Si. The evolution of crater development for Si .annealed at 500 [deg]C has a longer characteristic time compared to Si. These results are attributed to the fact that compared to Si, Si has a smaller surface binding energy of silicon atoms and a larger areal number density of silicon atoms on the plane perpendicular to the incident-ion axis. Furthermore, Si has a greater areal number density, smaller diameter, and a similar covered-area fraction of optically-detectable blisters compared to Si. However, Si has a lower areal number density and a smaller covered-area fraction of craters than does Si. Increasing post-annealing temperature from low (e.g. 400 [deg]C) to high (e.g. 500 [deg]C) revealed that Si tends to create more blisters while Si tends to develop larger blisters as well as create more craters.