When a reticle is first used, the reticle is loaded in a projection exposure device and measured by either oblique measurement or random measurement, thereby avoiding the fear of uneven sampling and determining the reticle transmittance of the entire reticle as the parent population, without increasing the sampling count. The same effect can be obtained by making the measurement spot size, which is fixed in general, variable and by changing the angle of incidence in relation to the measurement spot size.

A partial section of an aerial image measuring unit is arranged at a wafer stage and part of the remaining section is arranged at a measurement stage, and the aerial image measuring unit measures an aerial image of a mark formed by a projection optical system. Therefore, for example, when the aerial image measuring unit measures a best focus position of the projection optical system, the measurement can be performed using the position of the wafer stage, at which a partial section of the aerial image measuring unit is arranged, in a direction parallel to an optical axis of the projection optical system as a datum for the best focus position. Accordingly, when exposing an object with illumination light, the position of the wafer stage in the direction parallel to the optical axis is adjusted with high accuracy based on the measurement result of the best focus position.

A sensor for use in lithographic apparatus of an immersion type and which, in use, comes into contact with the immersion liquid is arranged so that the thermal resistance of a first heat path from a transducer of the sensor to a temperature conditioning device is less than the thermal resistance of a second heat flow path from the transducer to the immersion liquid. Thus, heat flow is preferentially towards the temperature conditioning device and not the immersion liquid so that temperature-induced disturbance in the immersion liquid is reduced or minimized.

A partial section of an aerial image measuring unit is arranged at a wafer stage and part of the remaining section is arranged at a measurement stage, and the aerial image measuring unit measures an aerial image of a mark formed by a projection optical system. Therefore, for example, when the aerial image measuring unit measures a best focus position of the projection optical system, the measurement can be performed using the position of the wafer stage, at which a partial section of the aerial image measuring unit is arranged, in a direction parallel to an optical axis of the projection optical system as a datum for the best focus position. Accordingly, when exposing an object with illumination light, the position of the wafer stage in the direction parallel to the optical axis is adjusted with high accuracy based on the measurement result of the best focus position.

A lithographic apparatus includes a substrate table capable of holding a substrate, a projection system that projects a patterned beam of radiation onto the substrate held by the substrate table, and a sensor table that is not capable of holding a substrate but that includes a sensor capable of sensing a property of the patterned beam of radiation. In addition, a first positioning system is connected to the substrate table and displaces the substrate table into and out of a path of the patterned beam of radiation, and a second positioning system is capable of positioning the sensor table into the path of the patterned beam of radiation when the substrate table is displaced out of the path of the patterned beam of radiation.

An analysis system that includes a processor and an memory module; wherein the memory module is arranged to store aerial images of an area of a mask, each aerial image corresponds to focus value out of a set of different focus values; wherein the processor is arranged to find weak points by processing the aerial images using different printability thresholds; and wherein the processor is arranged to determine focus and exposure values for generating a Process Window Qualification (PWQ) wafer to be manufactured using the mask in response to focus and exposure values associated with the weak points.

The problem of the presence of excess flare in maskless photolithography systems is addressed by systems and methods that utilize an aerial imaging system to monitor flare associated with the maskless photolithography systems.

A method for determining process window limiting patterns based on aberration sensitivity associated with a patterning apparatus. The method includes obtaining (i) a first set of kernels and a second set of kernels associated with an aberration wavefront of the patterning apparatus and (ii) a design layout to be printed on a substrate via the patterning apparatus; and determining, via a process simulation using the design layout, the first set of kernels, and the second set of kernels, an aberration sensitivity map associated with the aberration wavefront, the aberration sensitivity map indicating how sensitive one or more portions of the design layout are to an individual aberrations and an interaction between different aberrations; determining, based on the aberration sensitivity map, the process window limiting pattern associated with the design layout having relatively high sensitivity compared to other portions of the design layout.

A positioning apparatus in a lithographic apparatus for projecting a patterned beam of radiation onto a substrate has a first table connected to a first positioning system that displaces the first table into and out of a path of the patterned beam, and a second table connected to a second positioning system that displaces the second table into the path of the patterned beam when the first table is displaced out of the path of the patterned beam. The first and second tables, one of which is positioned in the path of the patterned beam of radiation, are moved relative to an immersion region formed with the supplied liquid under the projection system such that the immersion region is maintained under the projection system by the other of the first and second tables positioned in the path of the patterned beam in place of the one table.

The present invention relates to a method for simulating aspects of a lithographic process. According to certain aspects, the present invention uses transmission cross coefficients to represent the scanner data and models. According to other aspects, the present invention enables sensitive data regarding various scanner subsystems to be hidden from third party view, while providing data and models useful for accurate lithographic simulation.