Method for forming an alignment mark

A method, comprising:

• forming a trench structure with a first trench in a first section of a semiconductor body;
• forming a second trench that is wider than the first trench in a second section of the semiconductor body;
• and
• forming a semiconductor layer on a surface of the semiconductor body in the first section and the second section and in the first trench and the second trench, such that the semiconductor layer has a substantially planar surface above the first section and a residual trench remains above the second section,
• wherein forming the semiconductor layer comprises forming a first epitaxial layer in a first epitaxial growth process and a second epitaxial layer on top of the first epitaxial layer in a second epitaxial growth process,
• wherein the semiconductor body is a semiconductor wafer comprising a plurality of die sites and a kerf region, wherein the kerf region separates each of the die sites from one another, wherein the first trench is formed in one of the die sites, and wherein the second trench is formed in the kerf region,
• wherein the first epitaxial layer is a layer of monocrystalline semiconductor material, and
• wherein the monocrystalline semiconductor material of the first epitaxial layer completely fills the second trench.