Patent ID: 11948835
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 17:
18. A device comprising:
a first metal structure;
a dielectric structure over the first metal structure, the dielectric structure having a stepped sidewall structure, the stepped sidewall structure comprising a lower sidewall and an upper sidewall laterally set back from the lower sidewall;
a second metal structure extending through the dielectric structure, the second metal structure comprising a metal via laterally surrounded by the lower sidewall of the stepped sidewall structure of the dielectric structure, and a metal line laterally surrounded by the upper sidewall of the stepped sidewall structure of the dielectric structure; and
a dielectric residue located between the metal via and the lower sidewall of the stepped sidewall structure of the dielectric structure, and absent between the metal line and the upper sidewall of the stepped sidewall structure of the dielectric structure, wherein the dielectric structure forms an interface with an entire bottom surface of the dielectric residue at a position higher than a bottom surface of the metal via.