The fluence effect in hydrogen-ion cleaving of silicon at the sub-100-nm scale

• DOI: 10.1007/s00339-004-3094-z
• Publication Date: 2004-12-03T05:51:09Z
• Authors: O. Moutanabbir; B. Terreault; M. Chicoine; F. Schiettekatte
• Keywords: Channelling; Cleavage (geology); radiation damage

The implementation at the sub-100-nm scale of ion cleaving requires ion beams of ∼5 keV/amu or less. The blistering efficiency in 5-keV H-ion-implanted and annealed Si has been found to peak and vanish in a narrow range of ion fluence of (1.5–3.5)×1016 H/cm2. In order to understand this effect, the defect profiles in 5-keV H-irradiated Si were studied by Rutherford backscattering/channelling, while the Si-H bonding configurations during annealing were investigated by Raman scattering spectroscopy. Three types of defects play major roles: the ‘broad-band’ monohydride multivacancy complexes, the fully or partially passivated monovacancy VHn, and H-terminated internal surfaces Si(100):H. Blister absence at high fluence is characterised by the persistence up to 550 °C of the Si(100):H structures, which are blister embryos that failed to coalesce and grow. Radiation-induced stresses and fracture toughening may play roles in inhibiting cleavage at high fluence; however, widening towards the surface of the zone of high H and defect concentration is the likely major factor.