Abstract

This Letter describes the shock-induced amorphization of single-crystal Si bombarded by nanodroplets. At impact velocities of several kilometers per second, the projectiles trigger strong compression pulses lasting tens of picoseconds. The phase transition, confirmed via transmission electron microscopy and electron backscatter diffraction, takes place when the projectile’s stagnation pressure is approximately 15 GPa. We speculate that the amorphization results either from the decompression of the
beta-Sn phase or during the compression of the diamond phase.