An evaluation method for evaluating an aberration of a projection optical system in an exposure apparatus is provided. A first prediction coefficient of a first prediction formula for an aberration that is symmetrical with respect to an optical axis of the projection optical system is obtained, and a second prediction coefficient of a second prediction formula for an aberration that is asymmetrical with respect to the optical axis of the projection optical system is obtained. The aberration of the projection optical system is evaluated using the first prediction coefficient in a case where the shape of the illuminated region is determined as symmetrical with respect to the optical axis, and the aberration of the projection optical system is evaluated using the first and the second prediction coefficients in a case where the shape of the illuminated region is asymmetrical with respect to the optical axis.

A method localizes assembly errors during the arrangement and/or the assembly of in particular vibration-isolated structural elements, in particular of components of optical arrangements, preferably of microlithographic projection exposure apparatuses.

Disclosed is gas delivery system which is suitable for a high harmonic generation (HHG) radiation source which may be used to generate measurement radiation for an inspection apparatus. In such a radiation source, a gas delivery element delivers gas in a first direction. The gas delivery element has an optical input and an optical input, defining an optical path running in a second direction. The first direction is arranged relative to the second direction at an angle that is not perpendicular or parallel. Also disclosed is a gas delivery element having a gas jet shaping device, or a pair of gas delivery elements, one of which delivers a second gas, such that the gas jet shaping device or second gas is operable to modify a flow profile of the gas such that the number density of the gas falls sharply.

Embodiments described herein relate to a dynamically controlled lens used in lithography tools. Multiple regions of the dynamic lens can be used to transmit a radiation beam for lithography process. By allowing multiple regions to transmit the radiation beam, the dynamically controlled lens can have an extended life cycle compared to conventional fixed lens. The dynamically controlled lens can be replaced or exchanged at a lower frequency, thus, improving efficiency of the lithography tools and reducing production cost.

Embodiments of the disclosure relate to techniques and apparatus for reducing out-of-plane distortion (OPD) in a substrate, as well as control of the effects of OPD and the effects that the modifications made to the substrate to correct for the OPD have on subsequent substrate processing operations performed on the substrate. The present embodiments employ novel techniques to reduce the OPD in a substrate without adding or modifying portions of the substrate that will create issues in subsequent substrate fabrication processes.

Apparatus for and method of cleaning an electrically conductive surface of an optical element in a system for generating extreme ultraviolet radiation in which electrically conductive surface is used as an electrode for generating a plasma which cleans the surface.

An evaluation method for evaluating an aberration of a projection optical system in an exposure apparatus is provided. A first prediction coefficient of a first prediction formula for an aberration that is symmetrical with respect to an optical axis of the projection optical system is obtained, and a second prediction coefficient of a second prediction formula for an aberration that is asymmetrical with respect to the optical axis of the projection optical system is obtained. The aberration of the projection optical system is evaluated using the first prediction coefficient in a case where the shape of the illuminated region is determined as symmetrical with respect to the optical axis, and the aberration of the projection optical system is evaluated using the first and the second prediction coefficients in a case where the shape of the illuminated region is asymmetrical with respect to the optical axis.

A method and apparatus for non-contact measurement of stress in a thin-film deposited on a substrate is disclosed. The method may include positioning a substrate on a plurality of support-elements, the substrate having a thin-film deposited thereupon. A first-polynomial may be defined for representing a surface of the substrate that is in contact with the support elements. A second-polynomial may be determined based on an optimization determination of potential-energy acting upon the substrate. A finite-order polynomial may be created by calculating a product of the first and second polynomials to represent a shape of the surface of the substrate as a model of the surface. Thereafter, stress in the substrate may be determined based on fitting the model of the surface with a measured topographical data of the surface.

A component for a projection exposure apparatus includes a printed circuit board arranged in an encapsulated housing and having electronic component parts, and a heat conducting structure for dissipating heat from the electronic component parts to an outer side of the housing.

A porous member is used in a liquid removal system of an immersion lithographic projection apparatus to smooth uneven flows. A pressure differential across the porous member may be maintained at below the bubble point of the porous member so that a single-phase liquid flow is obtained. Alternatively, the porous member may be used to reduce unevenness in a two-phase flow.