Patent ID: 11914288
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Optics (Instruments)
Classification: CPC G  H | IPC G  H

Claim 12:
13. A method comprising:
providing a wafer comprising a photoresist layer;
exposing the photoresist layer to a pattern of radiation using a photomask, wherein the photomask comprises:
a substrate having a first recess and a second recess;
a first opaque main feature, a second opaque main feature, and a third opaque main feature over the substrate, wherein the first recess is between the first opaque main feature and the second opaque main feature, the second recess is between the second opaque main feature and the third opaque main feature, and a width of the second recess is greater than a width of the first recess and smaller than a width of the first opaque main feature; and
an opaque filling in one of the first recess and the second recess, wherein a top surface of the opaque filling is substantially coplanar with a top surface of the first opaque main feature; and

developing the photoresist layer after exposing the photoresist layer to the pattern of radiation.