A projection exposure apparatus for semiconductor lithography comprises an optical element and a temperature recording device for detecting a temperature on a surface of the optical element via electromagnetic radiation emanating from the surface of the optical element. The temperature recording device can comprise a filter for filtering the electromagnetic radiation.

A component of an optical system comprises an optical element and a first channel system outside the optical element and through which a cooling fluid can flow, such that, during operation of the optical system, heat generated by electromagnetic radiation incident on the optical element is absorbed and drawn off via the cooling fluid in the first channel system. The component also includes a second channel system through which a cooling fluid can flow to at least partially thermally shield a region of the component from the heat absorbed by the cooling fluid in the first channel system. The second channel system is outside the first channel system in the radial direction relative to the center of the optical element.

The invention provides a method for thermo-mechanical control of a heat sensitive element (Ml) subject to a heat load, comprising: -providing a non-linear thermo-mechanical model of the heat sensitive element describing a dynamical relationship between characteristics of the heat load and deformation of the heat sensitive element; -calculating a control signal on the basis of an optimization calculation of the non-linear model, -providing an actuation signal to a heater (HE), wherein the actuation signal is at least partially based on the control signal, -heating the heat sensitive element by the heater on the basis of the actuation signal.

An adaptive optical element for microlithography comprises at least one manipulator for changing the shape of an optical surface of the optical element. The manipulator comprises a one-piece dielectric medium which is deformable by applying an electric field, electrodes that are arranged in interconnection with the one-piece dielectric medium, and a voltage generator which is wired to the electrodes and configured to apply to the electrodes, firstly, a control voltage that serves to change a longitudinal extent of the dielectric medium and, secondly, an AC voltage that serves to heat the dielectric medium.

An adaptive optical element for microlithography comprises at least one manipulator for changing the shape of an optical surface of the optical element. The manipulator comprises a dielectric medium which is deformable via an electric field, work electrodes for generating the electric field in the dielectric medium, and a measuring electrode for measuring temperature. The measuring electrode is arranged in a direct assemblage with the dielectric medium. The measuring electrode has a temperature-dependent resistance.

A light source for EUV radiation is provided. The light source includes a target droplet generator, a laser generator, and a controller. The target droplet generator is configured to provide target droplets to a source vessel. The laser generator is configured to provide a plurality of first laser pulses according to a control signal to irradiate the target droplets in the source vessel to generate plasma as the EUV radiation. The controller is configured to provide the control signal according to the temperature of the source vessel and droplet positions of the target droplets. When the temperature of the source vessel exceeds a temperature threshold value and a standard deviation of the droplet positions of the target droplets exceeds a first standard deviation threshold value, the controller is configured to provide the control signal to the laser generator, so as to stop providing the first laser pulses.

A device (20) for detecting a temperature on a surface (15) of an optical element (14) for semiconductor lithography. The device includes an optical element (14) having a face (16) irradiated with electromagnetic radiation (7, 8, 43), a temperature recording device (21), and a temperature controlled element (22) configured to be temperature-controlled and arranged so that the predominant proportion of the intensity of the thermal radiation (25.2) detected by the temperature recording device and reflected by reflection at the surface of the optical element is emitted by the temperature-controlled element.

Also disclosed are an installation (1) for producing a surface (15) of an optical element (14) for semiconductor lithography and a method for producing a surface (15) of an optical element (14) of a projection exposure apparatus (30), wherein the surface is temperature-controlled and the surface temperature is detected during the temperature control.

A method of processing a substrate, includes emitting light including vacuum ultraviolet light to a front surface of the substrate, which has a resist film formed thereon from a resist material for EUV lithography, before an exposure process in an interior of a processing container.

A system and method for dynamically controlling a temperature of a thermostatic reticle. A thermostatic reticle assembly that includes a reticle, temperature sensors located in proximity to the reticle, and one or more heating elements. A thermostat component that is in communication with the temperature sensors and the heating element monitors the current temperature of the reticle relative to a steady-state temperature. In response to the current temperature of the reticle being lower than the steady-state temperature, the heating elements are activated to preheat the reticle to the steady-state temperature.

A method of manufacturing a semiconductor device by using an exposure apparatus having a reticle stage and a projection optical system includes a first period in which substrates are exposed by using a first reticle arranged on the reticle stage, a second period in which substrates are exposed by using a second reticle arranged on the reticle stage, and a third period which is between the first and second periods. The method includes changing, in at least part of the third period, the first reticle arranged on the reticle stage to the second reticle, and performing control, in the first and second periods, to adjust temperature distribution of an optical element of the projection optical system so as to reduce change in aberration of the projection optical system. The third period is shorter than the first period.