Method of forming alignment mark and method of manufacturing semiconductor device

摘要

A method of forming an alignment mark for specifying an optimum exposing position includes the steps of: preparing a substrate having a semiconductor element and an insulation film covering the semiconductor element; forming a resist pattern having a first opening on the insulation film, the first opening having a first width which is 1.25 times or less than a second width of a contact plug; forming a second opening with the first width in the insulation film; removing the resist pattern; forming a first conductive film on the insulation film and inside the second opening; and removing the first conductive film on the insulation film while leaving a portion of the first conductive film inside the second opening as an alignment mark.