Influence of the Chemical Activity of Implanted Ions on the Structure of the Damaged Si Layer in SIMOX Substrates

Abstract

High-resolution X-ray diffraction (HRXRD), X-ray reflectometry (XRR), X-ray photoelectron spectroscopy (XPS), and Atomic-force microscopy (AFM) were used to study the influence of the chemical activity of implanted ions (N+, O+, F+ or Ne+) on the structure of the damaged Si layer in SIMOX substrates. The implantation conditions were chosen so that the number of primary defects and the projected range were approximately the same for the implanted ions. HRXRD showed that the depth distribution of the residual damage depends on the chemical activity of the impurity. This may result from the quasi-chemical interaction between the radiation-induced point defects (VSi and Sii) and the impurity atoms. The shape of the density profiles and the thickness of the transition surface layer obtained from the XRR data are different for the implanted ions. The [100] faceted surface features of the samples prepared by SIMOX technology are preserved after implantation with the ions. AFM revealed a reduction of the lateral correlation length. The magnitude of this effect depends on the chemical activity of the implanted ions. Silicon oxidation at a depth of 10–15 nm is shown by XPS to change depending on the implanted ion.