Integrated circuit interconnect having dual dielectric intermediate layer

Claim 1

A method for forming an integrated circuit having a multilevel conductive interconnection comprising the following steps: providing an appropriate semiconductive integrated circuit substrate; forming a first metal pattern on said substrate; forming a blanket first dielectric layer of a first dielectric material on said first metal pattern so that said first dielectric material layer completely covers said first metal pattern; patterning said first dielectric layer to form an opening that exposes a selected surface portion of said first metal pattern; forming a blanket second dielectric layer of a second dielectric material on said first patterned dielectric layer so as to form a dual layer dielectric coating consisting of said first dielectric layer and said second dielectric layer, said second dielectric material being an organic material resistant to degradation at elevated temperatures; and patterning said second dielectric layer to form an opening in the second dielectric layer that wholly surrounds said opening in said first dielectric layer, effective to expose a surface of said first dielectric layer contiguous said exposed part of said selected portion of said first metal pattern, forming a second metal pattern upon said dual layer dielectric coating, said second metal pattern having a portion covering said opening in said second dielectric layer, so that said second metal pattern contacts said first metal pattern at said exposed part of said first metal pattern; effective to form a multilevel conductive interconnect having said dual dielectric coating intermediate said different levels of metal conductor everywhere except at said exposed part of said first metal pattern, where said metal patterns contact each other.

Claim 2

A method for forming an integrated circuit having a multilevel conductive interconnection comprising the following steps: providing an appropriate semiconductive integrated circuit substrate; forming a first metal pattern on said substrate; forming a blanket first dielectric layer of a first dielectric material on said first metal pattern so that said first dielectric material layer completely covers said first metal pattern; patterning said first dielectric layer to form an opening that exposes a selected surface portion of said first metal pattern; forming a blanket second dielectric layer of a second dielectric material on said first patterned dielectric layer so as to form a dual layer dielectric coating consisting of said first dielectric layer and said second dielectric layer, said second dielectric material being an organic material resistant to degradation at elevated temperatures; and patterning said second dielectric layer to form an opening in the second dielectric layer that wholly surrounds said opening in said first dielectric layer, effective to expose a surface of said first dielectric layer contiguous said exposed part of said selected portion of said first metal pattern, forming a second metal pattern upon said dual layer dielectric coating, said second metal pattern having a portion covering said opening in said second dielectric layer, so that said second metal pattern contacts said first metal pattern at said exposed part of said first metal pattern; effective to form a multilevel conductive interconnect having said dual dielectric coating intermediate said different levels of metal conductor everywhere except at said exposed part of said first metal pattern, where said metal patterns contact each other.

Claim 4

A method for forming an integrated circuit having a multilevel conductive interconnection comprising the following steps: providing a silicon integrated circuit substrate; forming a first metal pattern on said substrate; forming a blanket first dielectric layer of a first dielectric material chosen from the group consisting of silicon oxide or silicon nitride on said first metal pattern so that said first dielectric layer completely envelops said first metal pattern; patterning said first dielectric layer to form an opening that exposes a selected surface portion of said first metal pattern; forming a second dielectric layer of a photosensitive polyimide dielectric material on said first patterned dielectric layer so as to form a dual layer dielectric coating consisting of said first dielectric material and said polyimide, said dual dielectric coating having a substantially planarized surface; patterning said second dielectric layer to from an opening in the second dielectric layer that wholly surrounds the opening in said first dielectric layer, effective to expose a surface of said first dielectric layer surrounding said opening therein and form an exposed ring of said first dielectric layer surrounding said exposed part of said selected portion of said first metal pattern; forming a second metal pattern upon said substantially planarized surface of said dual layer dielectric coating, said second metal pattern having a portion covering said opening in said second dielectric layer, so that said second metal pattern contacts said first metal pattern at said exposed part of said first metal pattern; and depositing a third blanket layer of protective dielectric material upon said second metal conductor and any exposed regions of said second dielectric material; effective to form a multilevel conductive interconnect having said dual dielectric layer intermediate between said different levels of metal conductor everywhere except at said exposed part of said first metal pattern, where said metal patterns contact each other.

Claim 5

A method for forming an integrated circuit having a multilevel conductive interconnection comprising the following steps: providing a silicon integrated circuit substrate; forming a first metal pattern on said substrate; forming a blanket first dielectric layer of a first dielectric material chosen from the group consisting of silicon oxide or silicon nitride on said first metal pattern so that said first dielectric layer completely envelops said first metal pattern; patterning said first dielectric layer to form an opening that exposes a selected surface portion of said first metal pattern; forming a second dielectric layer of a photosensitive polyimide dielectric material on said first patterned dielectric layer so as to form a dual layer dielectric coating consisting of said first dielectric material and said polyimide, said dual dielectric coating having a substantially planarized surface; patterning said second dielectric layer to from an opening in the second dielectric layer that wholly surrounds the opening in said first dielectric layer, effective to expose a surface of said first dielectric layer surrounding said opening therein and form an exposed ring of said first dielectric layer surrounding said exposed part of said selected portion of said first metal pattern; forming a second metal pattern upon said substantially planarized surface of said dual layer dielectric coating, said second metal pattern having a portion covering said opening in said second dielectric layer, so that said second metal pattern contacts said first metal pattern at said exposed part of said first metal pattern; and depositing a third blanket layer of protective dielectric material upon said second metal conductor and any exposed regions of said second dielectric material; effective to form a multilevel conductive interconnect having said dual dielectric layer intermediate between said different levels of metal conductor everywhere except at said exposed part of said first metal pattern, where said metal patterns contact each other.