Investigation of deep implanted carbon and oxygen channeling profiles in [110] silicon, using d-NRA and SEM

摘要

Ion implantation is one of the most important techniques used in the silicon-based semiconductor industry. Using the ion axial channeling effect, which occurs when an ion beam is oriented along a crystallo-graphic axis, it is theoretically possible to implant ions deeper in the crystal, in comparison with the 'random' ion beam-solid orientation, while - at the same time - minimizing the induced crystal lattice damage. In the present work, 4 MeV ~(12)C~(2+) and 5 MeV ~(16)O~(2+) ions were implanted in high-purity [110] Si crystal wafers at fluences of the order of ～10~(17) particles/cm~2, in both the channeling and random orientations. The resulting profiles were measured using d-NRA, i.e. implementing the ~(12)C(d,p_0) and ~(16)O(d,p_0,α_0) reactions respectively, at E_(d,lab) = 1.2-1.4 MeV. The results were validated using SEM (Scanning Electron Microscopy), while the extent of crystalline damage was monitored during the implantation via RBS/C (Rutherford Backscattering Spectrometry/Channeling) spectra. The resulting profiles seem to be in good agreement with those obtained in the past for fluorine and nitrogen ions implanted in silicon, and clearly demonstrate the capabilities of high-energy channeling implantations, as well as, the accuracy of d-NRA (Nuclear Reaction Analysis) profiling measurements.