SEMICONDUCTOR SUBSTRATE AND METHOD FOR MANUFACTURING SAME

摘要

[PROBLEMS] To provide a semiconductor substrate having an alignment mark which can be used for alignment even after an impurity diffusion layer is formed by planarizing an epitaxial film. [MEANS FOR SOLVING PROBLEMS] A trench (11) is formed in an alignment region of an N⁺ substrate (1), and a void (3) is left after forming an N^- layer (2) by using the trench (11). The void (3) formed on the N⁺ substrate (1) can be used as an alignment mark. Thus, alignment in the subsequent semiconductor device manufacturing steps can be performed by using such semiconductor substrate, and each element constituting a semiconductor device can be accurately formed at a desired position.