Test structure for testing the depth of trench etchings in SOI wafers has a row of connected islands after etching insulating trenches, in which each island is surrounded by a trench which has a different width from island to island

摘要

Test structure has a row of connected islands (A-E) after etching insulating trenches, in which each island is surrounded by a trench which has a different width from island to island while including a trench that appears in the form of an insulating trench in an active circuit. A section of the surrounding trench (a-e) of each island forms a common piece with the trench of adjacent islands. The respective section has, in the inner islands, the width of the adjacent trench having the next larger or next smaller measure of width in the row. An independent claim is also included for a process for testing the depth of trench etchings in SOI wafers using the above structure.