Lateral growth of diamond based on precise seeding patterns using electron-beam lithography

A method is reported to produce patterns of diamond using electron-beam lithography, polymer-assisted seeding, and hot filament chemical vapor deposition (HFCVD). Seeded stripes range from 200 nm to 9 µm in width. Separation is varied to examine isolated and merged lateral growth. Scanning transmission electron microscopy (STEM) images confirm the growth of micron-scale polycrystals that grow vertically over the seeded areas and extend laterally over unseeded regions. The resulting diamond was studied using scanning electron and atomic force microscopies. The vertical diamond growth rates range between 0.46 and 0.56 µm/h. Lateral growth rates show decreasing trend, from 0.48 to 0.20 µm/h, as initial seeding stripe widths increase. The results show that decreasing the initial seeding stripe width increases the lateral growth rate with comparable crystal quality. The effect of the gap between seeding stripes on the growth rates has been investigated in the range where separations are “large” for producing substrate coverage that is primarily direct growth on the unseeded substrate area. Ultraviolet (UV) micro-Raman line scans were used to examine the diamond grown directly on the seeded regions and the lateral growth over the unseeded substrate. Micro-Raman stress maps confirm the grown diamond to be directly bonded to the substrate where lateral overgrowth has taken place.