A method for operating an optical apparatus (100A, 100B, 200), having a structural element (201) which is arranged in a residual gas atmosphere (RGA) of the apparatus and which is formed at least partly from an element material subjected to a chemical reduction process and/or an etching process with a plasma component (PK) present in the residual gas atmosphere includes: feeding (S2) a gas component (GK) that at least partly suppresses the reduction process depending on a detected suppression extent (UM) for a suppression of the etching process and/or reduction process by the suppressing gas component in the residual gas atmosphere; and detecting (S1) the suppression extent with a sensor unit (208) arranged in the residual gas atmosphere. The sensor unit includes a sensor material section (211) composed of a sensor material and exhibiting a sensor section property that is measurable under the influence of the suppressing gas component.

A lithographic projection apparatus is disclosed in which a space between the projection system and a sensor is filled with a liquid.

An objective lens protection device, objective lens system and lithographic device. The objective lens protection device includes a main structure provided with, oppositely disposed, an air supply unit and extraction unit. The air supply unit is used to output air. The extraction unit extracts air output by the air supply unit to form at least one layer of air curtain between the air supply unit and extraction unit. The objective lens protection device can effectively control the flow rate of wind discharge, controlling wind in a laminar flow state and ensuring uniform flow field of the air curtain, and can effectively block organic matters volatilized from the bottom up, eliminate opportunity for a direct contact of the organic matters with the lens, and prevent objective lens from contamination by the volatilization of the organic matters of photoresist, thus ensuring the imaging quality of the objective lens.

The present application is directed to an improved immersion grating assembly that provides additional wavelength dispersion and higher optical efficiency at ultraviolet wavelengths relative to prior art devices. More specifically, the immersion grating disclosed herein may be used to narrow the spectrum of light emitted by excimer laser systems. Narrower spectral linewidth of excimer laser systems may enable the creation of smaller feature sizes in semiconductor structures manufactured using UV photolithography processes.

Extreme ultraviolet (EUV) exposure apparatuses and methods, and methods of manufacturing a semiconductor device by using the exposure method, which minimize an error caused by a mirror in an EUV exposure process to improve an overlay error, are provided. The EUV exposure apparatus includes an EUV source configured to generate and output EUV, first illumination optics configured to transfer the EUV to an EUV mask, projection optics configured to project the EUV, reflected from the EUV mask, onto an exposure target, a laser source configured to generate and output a laser beam for heating, and second illumination optics configured to irradiate the laser beam onto at least one mirror included in the projection optics.

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.

Disclosed is 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 pump radiation source is operable to emit pump radiation at a high harmonic generation gas medium thereby exciting the high harmonic generation gas medium within a pump radiation interaction region so as to generate the high harmonic radiation and an ionization radiation source is operable to emit ionization radiation at the high harmonic generation gas medium to ionize a gas at an ionization region between the pump radiation interaction region and an optical output of the illumination source.

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.

An optical system can include an optical arrangement supported by an optical chassis. A flexure arrangement can support the optical chassis relative to a separate structure to maintain a calibrated distance between optical components of the optical arrangement.

The present invention relates to a lithographic apparatus, comprising: a projection system configured to project a patterned radiation beam onto a substrate, comprising optical elements, a sensor frame, a first position measurement system configured to measure a position of an optical element relative to the sensor frame, comprising a sensor adapted to monitor an optical element, with a sensor element mounted to the sensor frame, a sensor frame support supporting the sensor frame on a reference, a force measurement device adapted to generate force measurement data relating to force exerted on the sensor frame by the sensor frame support, a position control device adapted to control the relative position of the substrate and the patterned radiation beam wherein the position control device is configured to receive the force measurement data and to control said relative position based on at least the force measurement data.