Dual damascene structure employing laminated intermediate etch stop layer

A method for forming a dual damascene aperture comprising:

• providing a substrate having formed therein a contact region;
• forming upon the substrate and the contact region a blanket first etch stop layer;
• forming upon the blanket first etch stop layer a patterned first dielectric layer having formed aligned thereupon a patterned second etch stop layer in turn having formed thereupon a patterned second dielectric layer which leaves exposed a top surface portion of the patterned second etch stop layer, the foregoing series of patterned layers defining an aperture aligned above the contact region and having as bottom surfaces exposed top surface portions of the patterned second etch stop layer and the blanket first etch stop layer;
• and
• etching completely through the blanket first etch stop layer to reach the contact region while not etching completely through the patterned second etch stop layer to reach the patterned first dielectric layer to thus form from the aperture a dual damascene aperture, wherein:
• the blanket first etch stop layer is formed of a first etch stop material;
• and
• the blanket second etch stop layer is formed as a laminate of a second etch stop material having formed thereupon a third etch stop material.