The damage production in the Si9Ge6 superlattices (SLs) upon implantation of 150 keV Ar+ ions at 300 K was studied my means of the cross-sectional transmission electron microscopy (XTEM) and electron microdiffraction. It was found that the amorphization occurs in a narrow dose range of (1 – 2) × 1014 cm-2 via accumulation of point defects. The conclusion drawn earlier (Mater. Sci. Forum 248-249, 289 (1997)) on the coherent amorphization of the Si and Ge layers in the SLs was confirmed. Possible mechanisms of the layer interaction leading to the observed behavior are discussed.