Epitaxial structure with pattern mask layers for multi-layer epitaxial buffer layer growth

摘要

An epitaxial structure including an epitaxial substrate, a first buffer layer, a first pattern mask layer, a second buffer layer and a second pattern mask layer. The first buffer layer is disposed on the epitaxial substrate. The first pattern mask layer is disposed on the first buffer layer. The second buffer layer is disposed on the first pattern mask layer and a part of the first buffer layer. The second pattern mask layer is disposed on the second buffer layer. A projection of the first pattern mask layer projected on the first buffer layer and a projection of the second pattern mask layer projected on the first buffer layer cover at least 70% of the total area of the first buffer layer.