| abstract |
A semiconductor substrate having a trench groove in which an epitaxial film is buried and having a region whose surface is flattened, and an alignment mark forming region having a highly recognizable alignment mark and its manufacture Provide a method. An alignment pattern composed of trench grooves is formed in an alignment mark formation region A1, and a translucent film material 3a is formed so as to cover the alignment pattern. Next, a trench groove 22 is formed in the diffusion layer formation region A2, and the epitaxial film 4 is formed in a manner to fill the trench groove 22. Thereafter, the alignment mark M1a is formed by performing a planarization process on the substrate surface in a state where the alignment pattern is covered with the film material 3a. The alignment mark M1a formed in this way is used to perform mask alignment between the diffusion layer pattern and a mask pattern to be processed in a subsequent process. [Selection] Figure 2 |