Patent · US Active

Method and apparatus for forming self-aligned via with selectively deposited etching stop layer

US9659864B2 · kind B2 · utility

21Cited by
16References
20Claims
0Family size

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Key dates

Filing dateOct 20, 2015
Grant dateMay 23, 2017
Priority date
Expiry dateOct 20, 2035

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L23/532
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A layer of an interconnect structure is formed over a substrate. The layer contains an interlayer dielectric (ILD) material and a metal line disposed in the ILD. A first etching stop layer is formed on the ILD but not on the metal line. The first etching stop layer is formed through a selective atomic layer deposition (ALD) process. A second etching stop layer is formed over the first etching stop layer. A high etching selectivity exists between the first and second etching stop layers. A via is formed to be at least partially aligned with, and electrically coupled to, the metal line. The first etching stop layer prevents the ILD from being etched through during the formation of the via.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.