Patent ID: 11952656
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Surface technology, coating (Chemistry)
Classification: CPC C  H | IPC C  H

Claim 7:
8. A method of using a physical vapor deposition (PVD) system, the method comprising:
holding a semiconductor wafer with a pedestal;
holding a target with a cover plate;
with a first plurality of passages of a collimator, passing source material travelling from the target toward the pedestal at an angle less than a first threshold angle with respect to a line perpendicular to a surface of the pedestal facing the cover plate;
with a second plurality of passages of the collimator, passing source material travelling from the target toward the pedestal at an angle less than a second threshold angle with respect to the line;
with a first plurality of sidewall sheets of the collimator, blocking source material travelling from the target toward the pedestal at an angle greater than the first threshold angle with respect to the line; and
with a second plurality of sidewall sheets of the collimator, blocking source material travelling from the target toward the pedestal at an angle greater than the second threshold angle with respect to the line,
wherein the first threshold angle is greater than the second threshold angle;
a central portion of the collimator has a cross sectional shape defined by a rectangle from which a trapezoid has been subtracted to form a cutout, wherein the first plurality of passages are in the central portion and the second plurality of the passages are outside the central portion.