Self-aligned eetching process

摘要

The invention describes a self-aligned etching process. A conductive layer and a first insulating layer are formed on a substrate in sequence, and then the conductive layer and the first insulating layer are patterned to form a plurality of stacks on desired regions. Subsequently, spacers are formed on sidewalls of each stack, and a stop layer is then formed on the substrate. A second insulating layer is formed on the substrate and is planarized. Portions of the second insulating layer are removed to form a plurality of openings and to expose portions of the stop layer located between spacers. The exposed stop layer is removed.