We have developed the zone-heating recrystallization (ZHR) method, the high-speed scanning lamp heating below the melting point of Si, for the selective heat treatment of the Si surface (Fig. 2) . By applying ZHR to the epitaxy and layer transfer process on DLPS by RVD, we obtained the 9 µm-thick monocrystalline Si thin film with only 1-min epitaxy .
In this work, we controlled nanometer-size roughness of DLPS surface by ZHR and investigated the properties of Si thin film grown with RVD. To investigate the quality of thin film Si by both XRD and electron spin resonance (ESR), RVD were carried out with intrinsic Si wafer as Si source to avoid the signal of electron from the dopant. ~9 µm intrinsic Si thin films were grown and they could be easily detached by transferring to scotch tape. The Si films with different root mean square roughness (Rms), pore size and pore number density which were grown on DLPS with/without ZHR in several condition were picked up and analyzed.
DLPS were formed on p-type monocrystalline Si (100) wafer by two-step anodization. ZHR were carried out with different input power into bottom heater and scanning rate of top lamp heater, and DLPS with different Rms (0.23-0.39 nm) observed by AFM were obtained as described in the previous report . In Si film grown by RVD on the DLPS by each ZHR condition, in-plane XRD Φ-scan of (022) diffraction showed clear four fold symmetry, which proves that the epitaxial monocrystalline film of Si(100) obtained regardless of ZHR conditions. The effect of the surface roughness of DLPS on the crystallographic quality of epitaxial Si films will be discussed.
In summary, the epitaxial monocrystalline film by RVD was obtained by the selective heat treatment of Si surface of DLPS by ZHR. The intrinsic monocrystalline film with 9 µm by RVD on DLPS could be easily detached from Si wafer to evaluate crystallographic quality by ESR.
 Y. Yamasaki et al., CrystEngComm 18, 2016. 3404.
 A. Lukianov et al., Appl. Phys. Lett. 108, 2016, 1.