Formation of SIMOX-SOI structure by high-temperature oxygen implantation

We have performed oxygen ion implantation in silicon at very high substrate-temperatures (<= 1000 degrees C) for the purpose of forming silicon-on-insulator (SOI) structure. We have expected that the hightemperature implantation can effectively avoids ion-beam-induced damages in the SOI layer and simultaneously stabilizes the buried oxide (BOX) and SOI-Si layer. Such a high-temperature implantation makes it possible to reduce the post-implantation annealing temperature. In the present study, oxygen ions with 180 key are incident on Si(001) substrates at various temperatures from room temperature (RT) up to 1000 degrees C. The ion-fluencies are in order of 10(17)-10(18) ions/cm(2). Samples have been analyzed by atomic force microscope, Rutherford backscattering, and micro-Raman spectroscopy. It is found in the AFM analysis that the surface roughness of the samples implanted at 500 degrees C or below are significantly small with mean roughness of less than 1 nm, and gradually increased for the 800 degrees C-implanted sample. On the other hand, a lot of dents are observed for the 1000 degrees C-implanted sample. RBS analysis has revealed that stoichiometric SOI-Si and BOX-SiO2 layers are formed by oxygen implantation at the substrate temperatures of RT, 500, and 800 degrees C. However, SiO2-BOX layer has been desorbed during the implantation. Raman spectra shows that the ion-beam-induced damages are fairly suppressed by such a high-temperatures implantation. (C) 2015 Elsevier B.V. All rights reserved.