AN INSPECTION TOOL, METHOD AND LITHOGRAPHIC APPARATUS

摘要

[0007] According to a first aspect of the invention, there is provided a tool for assessing a hole property of one or more holes in a component of a lithographic apparatus, the tool comprising: an assessment substrate; a fluid supply configured to supply a jet of fluid from each of the one or more holes to a first surface of the assessmeni substrate, wherein the fluid is supplied at a fluid temperature such that the one or more jets of fluid cause local temperature variations in at least part of the assessment substrate; and an infrared sensor configured to sense a temperature distribution of the assessment substrate in dependence on the local temperature variations. [0008] According to a second aspect of the invention, there is provided a method of assessing a hole property of one or more holes in a component of a lithographic apparatus, the method comprising: providing an assessment substrate; supplying a jet of fluid from each of the one or more holes to a first surface of the assessment substrate, wherein the fluid is supplied at a fluid temperature such that the one or more jets of fluid cause local temperature variations in at least part of the assessment substrate; sensing, by an infrared sensor, a temperature distribution of the assessment substrate in dependence on the local temperature variations; assessing the hole property in dependence on the sensed temperature distribution.[0009] Further embodiments, features and advantages of the present invention, as well as the structure and operation of the various embodiments, features and advantages of the present invention, are described in detail below with reference to the accompanying drawings.