Patent ID: 11966170
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Optics (Instruments)
Classification: CPC G  H | IPC G  H

Claim 13:
14. A method comprising:
receiving a wafer;
measuring a surface topography of the wafer;
calculating a topographical variation based on the surface topography measurement;
determining to perform a single-zone alignment compensation when the topographical variation is less than a predetermined value, and alternatively, to perform a multi-zone alignment compensation when the topographical variation is greater than the predetermined value; and
performing a wafer alignment according to the single-zone alignment compensation or the multi-zone alignment compensation,
wherein the single-zone alignment compensation further comprises:
defining an edge zone over the wafer, wherein the edge zone includes a plurality of fields; and
performing the single-zone alignment compensation by a controller for the edge zone;

wherein the multi-zone alignment compensation further comprises:
defining a plurality of zones over the wafer, wherein the plurality of zones includes a first zone, a second zone and an Nth zone, and each of the first zone, the second zone and the Nth zone includes a plurality of fields;
performing a first multi-zone alignment compensation by the controller to obtain a first compensation value for the fields in the first zone, wherein the first multi-zone alignment compensation includes an equation (1), and the equation (1) is:

dX1=α1*Z1+β1*Z2+γ1*Z3+ . . . ω1*Zn  (1)

wherein dX1 indicates the first compensation value for the fields in the first zone, Z1 to Zn indicate the first zone to the Nth zone of the plurality of zones, α1 indicates a weighting for the fields in the first zone in the first multi-zone alignment compensation, β1 indicates a weighting for the fields in the second zone in the first multi-zone alignment compensation, γ1 indicates a weighting for the fields in the third zone in the first multi-zone alignment compensation, and ω1 indicates a weighting for the fields in the Nth zone in the first multi-zone alignment compensation; and
performing a second multi-zone alignment compensation by the controller to obtain a second compensation value for the fields in the second zone, wherein the second multi-zone alignment compensation includes an equation (2), and the equation (2) is:

dX2=α2*Z1+β2*Z2+γ2*Z3+ . . . ω2*Zn  (2)

wherein dX2 indicates the second compensation value for the fields in the second zone, α2 indicates a weighting for the fields in the first zone in the second multi-zone alignment compensation, β2 indicates a weighting for the fields in the second zone in the second multi-zone alignment compensation, γ2 indicates a weighting for the fields in the third zone in the second multi-zone alignment compensation, and ω2 indicates a weighting for the fields in the Nth zone in the second multi-zone alignment compensation.