Systems, devices, and methods for registering a superstrate of an imprint tool
AssigneeCanon Kabushiki Kaisha
InventorsXiaoming Lu, Jeffrey Dean Klein
Life of this patent
Estimating the term…
Abstract
Some devices, systems, and methods hold a periphery of a back surface of a plate with a flexible ring portion of a chuck assembly; apply a negative vacuum pressure to a central portion of the back surface of the plate to bow the central portion of the plate such that the back surface of the plate forms a convex surface and a front surface of the plate forms a concave surface; measure, at or near the periphery of the plate, distances between the plate and a reference location; and identify a location of a transition point of a tapered edge of the plate based on the measured distances.
Claims20
A method of measuring a tapered edge on a plate, the method comprising:
- holding a periphery of a back surface of a plate with a flexible ring portion of a chuck assembly;
- applying a negative vacuum pressure to a central portion of the back surface of the plate to bow the central portion of the plate such that the back surface of the plate forms a convex surface and a front surface of the plate forms a concave surface;
- measuring, at or near the periphery of the plate, distances between the plate and a reference location;
- and
- identifying a location of a transition point of a tapered edge of the plate based on the measured distances.
An imprint system comprising:
- a sensor;
- a vacuum pump;
- a superstrate chuck including a flexible ring portion, wherein the flexible ring portion is configured to hold a periphery of a back surface of a plate;
- one or more memories;
- and
- one or more processors, wherein the one or more processors and the one or more memories cooperate to cause the imprint system to perform operations that comprise:
- controlling the vacuum pump to generate an atmospheric pressure at a central portion of the back surface of the plate that is lower than an atmospheric pressure at the central portion of a front surface of the plate such that the back surface of the plate forms a convex surface and the front surface of the plate forms a concave surface;
- controlling the sensor to measure, at each measuring point of a plurality of measuring points at or near the periphery of the front surface the plate, a distance between the measuring point and a reference location;
- and
- identifying a respective location of each transition point of one or more transition points of a tapered edge of the plate based on the respective distance at each measuring point of the plurality of measuring points.
A method comprising:
- holding a periphery of a back surface of a plate with a flexible ring portion of a chuck, wherein the plate includes a front surface, wherein the front surface includes a contact surface that is surrounded by a sloping edge, and wherein, between the contact surface and an edge of the plate, the sloping edge slopes away from the contact surface toward the back surface;
- reducing an atmospheric pressure at a central portion of the back surface of the plate such that the back surface of the plate forms a convex surface and the front surface of the plate forms a concave surface;
- measuring, for each point of a plurality of points on the front surface of the plate that are at or near a periphery of the front surface of the plate, a respective distance between the point and a plane of the chuck;
- and
- identifying at least one transition point between the sloping edge and the contact surface based on the respective distances.
Dependencies are inferred from the claim text.