The disorder produced by 0.3‐MeV D+random bombardment in Si and Ge crystal targets has been investigated with 1.5‐MeV D+channeling measurements. An increase of about 30–50% in the ⟨111⟩‐ and ⟨110⟩‐aligned yields of Ge samples has been found after a bombardment with a dose of 200–300 &mgr;C/cm2. No significant increase was observed in bombarded Si samples. Detailed angular scans suggest a ``spread‐out'' distribution of defects imbedded in the lattice structure.