Patent ID: 11960211
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 1:
2. A lithography system comprising:
an energy source;
a wafer chuck for holding a semiconductor wafer;
a mask chuck configured to support a photomask over the semiconductor wafer, wherein the mask chuck is also configured to allow gravitational effects to cause the photomask to sag at a center of the photomask such that a major patterned surface of the photomask has a first curvature, the first curvature having a first radius greater than zero, the wafer chuck having a top surface with a curvature matching the first curvature, the top surface of the wafer chuck being configured to hold the semiconductor wafer to have the first curvature; and
a light pipe used to direct energy from the energy source through the photomask to the wafer chuck, the light pipe being between the energy source and the photomask.