ALIGNMENT PATTERN AND ITS FORMING METHOD

摘要

PURPOSE: To provide an alignment pattern and its forming method in which a peak can be read out readily by detecting a level difference surely through scanning even when planarization is performed by CMP without requiring any extra process. CONSTITUTION: The alignment pattern used for patterning wiring of an aluminum film 15 comprises a planar shape of an inclining face formed between the upper edge of an alignment hole 12 opened in a BPSG film 20 on a silicon substrate 18, and the surface of a tungsten plug 14 filling the alignment hole 12 wherein the alignment hole 12 is formed deeper than the thickness of the BPSG film 20. The alignment hole 12 enters or penetrates a field oxide film 13 formed on the silicon substrate 18.