Study of high-temperature Smart Cut™: Application to thin films of single crystal silicon and silicon-on-sapphire films

This paper presents results introducing a novel method of fabrication of thin silicon films based on combination of film separation by Smart Cut™ technology and a high temperature liquid phase epitaxy. The separation kinetics of the substrate is characterized for silicon, implanted with a dose of 5.0×10¹⁶ H×cm^-2 and an implantation energy of 60 keV, over a range of temperature from 450°C to 700°C. The out-diffusion of hydrogen is studied by Energy Recoil Detection Analysis and a model of diffusion of hydrogen in silicon, taking into account the implantation damages, is proposed. Based on this kinetics analysis, Smart Cut™ separation is proceeded at temperature superior to 1100°C, considering an implanted silicon wafer bonded with a sapphire wafer, through which, a laser beam anneals the structure. Finally, this article presents results of liquid silicon deposition onto an implanted silicon substrate. The last ones show the possibility to detach the grown film and the upper part of the implanted substrate by Smart Cut™ during the step of liquid phase epitaxy. Electron Backscattering Diffraction Pattern analysis is considered in order to demonstrate the occurrence of epitaxy of the deposited liquid onto the implanted substrate.