Nanocavities created in Ge(111) by 5 keV Xe ion irradiation are characterized by ex situ transmission electron microscopy (TEM). Nanocavities with average diameter of 10 nm are observed at 500 degreesC, while nanocavities with average diameter of 2.9 nm are observed at 400 degreesC. The nanocavities grow beyond equilibrium size at 500 degreesC mainly due to absorption of vacancies produced during 5 keV Xe ion irradiation. The sink strengths of the nanocavities and the Ge surface for absorption of interstitials and vacancies are examined to elucidate the growth of the nanocavities in the absence of apparent biased sinks such as dislocations. (C) 2004 Elsevier B.V. All rights reserved.