In-Plane Grain Orientation Alignment of Polycrystalline Silicon Films by Normal and Oblique-Angle Ion Implantations

摘要

Random crystallographic orientations of polycrystalline silicon (poly-Si) grains in the films grown on a SiO_2 substrate by chemical vapor deposition were laterally aligned by maintaining the {110} restricted pillar texture through double Si~+ self-ion implantations. The in-plane X-ray diffraction pattern and rocking curve clearly indicate the lateral alignment. The oblique-angle Si~+ self-ion implantation was also found to be useful for increasing the amount of the {110} pillar texture. The electron backscatter diffraction (EBSD) pattern supports the increase in the amount of the {110} pillar texture and the lateral crystal orientation alignment. The transmission electron micrography and EBSD results also suggest that grain size is increased by double Si~+ self-ion implantations. Although further systematic optimization may be required, the technique will be useful for improving the electrical characteristics of poly-Si devices for future electronic systems on insulators.