Patent ID: 6399511
Filing Date: 2002-06-04
Classification: H01L

Abstract:
A multi-level dielectric etch method, comprising the steps of:placing into a plasma reactor a substrate containing a layered structure formed over a substrate and comprising sequentially, from a bottom thereof, a first stop layer, a first dielectric layer, a second stop layer, a second dielectric layer, and a first photomask patterned with at least one first aperture; a first flowing step of flowing a first gas mixture into said reactor and exciting it into a first plasma, said first plasma capable of etching both said second dielectric layer and said second stop layer through said at least one first aperture; continuing said first step at least until said second stop layer is etched through; and a second flowing step, performed without removing said substrate from said reactor after said first flowing step, of flowing a second gas mixture into said reactor and exciting it into a second plasma, said second plasma etching said first dielectric layer through said at least one first aperture selectively to said first stop layer.