Graphite base

The invention provides a graphite base, and belongs to the technical field of epitaxial growth. A first surface of the graphite base is provided with a plurality of openings, the first surface is further provided with at least one concave-convex structure, the concave-convex structure comprises an annular groove and an annular protrusion, the annular groove surrounds the multiple openings, and the annular protrusion surrounds the annular groove. According to the graphite base, the growth quality of an epitaxial wafer in the groove close to the edge of a reaction cavity in the graphite base can be improved, and the overall uniformity of the epitaxial wafer in the graphite base is improved. 本公开提供了一种石墨基座，属于外延生长技术领域。该石墨基座的第一表面具有多个开口，所述第一表面还具有至少一个凹凸结构，所述凹凸结构包括环形凹槽和环形凸起，所述环形凹槽围绕在所述多个开口外，所述环形凸起围绕在所述环形凹槽外。本公开能提高石墨基座中靠近反应腔边缘位置的凹槽内外延片的生长质量，改善石墨基座内外延片整体的均匀性。