We report the first study of the effect of in situ ultrasound treatment during ion implantation on amorphization and transient enhanced diffusion (TED) in silicon. Rutherford backscattering spectroscopy, ion channeling, and Raman spectroscopy measurements show that amorphization of Si during Ar ion implantation is increased by ultrasound treatment, especially at ultrasound frequencies around 2 MHz. By secondary ion mass spectroscopy we investigate the influence of ultrasound treatment on TED of B atoms. Our data show that TED is reduced due to the influence of ultrasound treatment. The results are discussed in terms of the interaction of ultrasound waves with point defects and the ultrasound stimulated enhanced diffusion of interstitials.