Lateral diffusion epitaxy (LDE) of single crystal silicon with downward facing substrate

An increase in the aspect ratio of silicon platelets grown by Lateral Diffusion Epitaxy (LDE) is achieved. Epitaxial growth is achieved by a compound graphite slider boat in which an oxidized silicon plate is placed above the seed line on the substrate. The function of the plate is to i) favor side wall growth by limiting vertical nucleation on the platelets, and ii) to enhance the surface smoothness by restricting diffusion of silicon to a horizontal direction. We have studied layer growth from the In-Si liquid phase by reducing the gap between substrate and plate. By reducing the gap, it allows for a more uniform growth of silicon from the side wall of the strip. In addition, we investigate repositioning the silicon seed line to a downward orientation. In this case, the diffusion rate increases due to a gravity effect.