Imprint lithography method

摘要

An imprint lithography apparatus and manufacturing method can lead to mechanical stress being formed in a substrate to which an imprint pattern is being applied. This may cause strain within the substrate leading to misalignment of a subsequent pattern with an earlier pattern in a part of the substrate, which is strained. An apparatus and method is disclosed which allows for stress relaxation in the substrate prior to further patterning to reduce, minimize or prevent such misalignment from residual strain. This is achieved by locally unclamping a portion of substrate (including optionally the entire substrate) from a corresponding portion of substrate holder so that mechanical stress leading to local strain may relax prior to further patterning. To overcome residual frictional force between the substrate and substrate holder, the substrate and substrate holder may be physically separated prior to further patterning.

主权项

1. A method of patterning a substrate, the method comprising:
patterning the substrate while the substrate is at least partially releasably clamped to a substrate holder, the substrate holder comprising at least three movable parts configured to contact the substrate, each movable part able to move separately and independently of the other movable parts; unclamping a first portion of the substrate from a corresponding portion of the substrate holder such that stress in the substrate is relaxed; displacing at least one of the three movable parts of the substrate holder to apply a force, or to remove application of a force, to directly cause the unclamped first portion of substrate to be separated by a gap from the corresponding portion of substrate holder prior to carrying out further patterning of the substrate; re-clamping the separated first portion of substrate to the substrate holder; and carrying out the further patterning of the substrate with the first portion of substrate clamped on the substrate holder, wherein the substrate does not come out of contact with the substrate holder after the separation of the first portion of the substrate until, and including, the further patterning.