Abstract:
Disclosed is a cleaning apparatus configured to clean a radiation transmission assembly (such as a viewport), or part thereof. The radiation transmission assembly provides for radiation transmission to and/or from a low pressure chamber. The cleaning apparatus comprises, a hydrogen radical generator configured to generate hydrogen radicals for use in cleaning said radiation transmission assembly or part thereof, and a connection assembly for connection to said radiation transmission assembly.
Abstract:
The invention relates to a method for at least partially removing a contamination layer (15) from an optical surface (14a) of an EUV-reflective optical element (14) by bringing a cleaning gas, preferably comprising atomic hydrogen, into contact with the contamination layer (15), the method comprising the steps of: directing a jet (20) of cleaning gas to the contamination layer (15) for removing material from the contamination layer (15), monitoring the contamination layer (15) for generating a signal indicative of the thickness of the contamination layer (15), and controlling the jet (20) of cleaning gas by moving the jet (20) of cleaning gas relative to the optical surface (14a) using the signal indicative of the thickness of the contamination layer (15) as a feedback signal, and to a corresponding cleaning arrangement (19 to 24). The invention further relates to a method for generating a jet (20) of cleaning gas, as well as to a corresponding cleaning gas generation arrangement.
Abstract:
The invention relates to an optical element (50), comprising: a substrate (52), an EUV radiation reflecting multilayer system (51) applied to the substrate (52), and a protective layer system (60) applied to the multilayer system (51) and having at least a first and a second layer (57, 58), wherein the first layer (57) is arranged closer to the multilayer system (51) than the second layer (58). The first layer (57) serves as a diffusion barrier for hydrogen and has a lower solubility for hydrogen than the second layer (58), which serves for absorbing hydrogen. The invention also relates to an optical system for EUV lithography which comprises at least one such optical element (50), and to a method for treating an optical element (50) in order to remove hydrogen incorporated in at least one layer (57, 58, 59) of the protective layer system (60) and/or in at least one layer (53, 54) of the multilayer system (51).
Abstract:
The invention relates to a method for optimizing a protective layer system (59) for an EUV radiation (6) reflecting multilayer system (51) of an optical element (50), comprising the following steps: selecting a material for a topmost layer (57) of the protective layer system (59) from a group of chemical compounds comprising: oxides, carbides, nitrides, silicates and borides, wherein selecting the material for the topmost layer (57) is effected depending on an enthalpy of formation of the respective chemical compound. The invention also relates to an optical element (50), comprising: an EUV radiation (6) reflecting multilayer system (51), and a protective layer system (59) having a topmost layer (57) composed of a material selected from a group of chemical compounds comprising: oxides, carbides, nitrides, silicates and borides, wherein the protective layer system (59) either consists of the topmost layer (57) having a thickness (d) of between 5 nm and 15 nm, or the protective layer system (59) has at least one further layer (58) below the topmost layer (57), the thickness (d 2 ) of which is greater than the thickness (d 1 ) of the topmost layer (57), and wherein the topmost layer (57) has a thickness (d-i) of not more than 5 nm and a thickness (d2) of the further layer (58) or of the further layers is greater than 5 nm.
Abstract:
An apparatus comprising: a radiation receiving apparatus provided with an opening operable to receive radiation from a radiation source through the opening; wherein the radiation receiving apparatus comprises a deflection apparatus arranged to change a trajectory of a particle through the opening arriving at the radiation receiving apparatus.
Abstract:
Die Erfindung betrifft ein EUV-Lithographiesystem (1), umfassend: mindestens ein optisches Element (13, 14) mit einer optischen Oberfläche (13a, 14a), die in einer Vakuum-Umgebung (17) des EUV-Lithographiesystems (1) angeordnet ist, sowie eine Zuführungseinrichtung (27) zur Zuführung von Wasserstoff in die Vakuum-Umgebung (17), in der mindestens eine Silizium enthaltende Oberfläche (29a) angeordnet ist. Die Zuführungseinrichtung (27) ist zur zusätzlichen Zuführung eines Sauerstoff enthaltenden Gases in die Vakuum- Umgebung (17) ausgebildet und weist eine Dosiereinrichtung (28) zur Einstellung eines Sauerstoff-Partialdrucks (P02) an der mindestens einen Silizium enthaltenden Oberfläche (29a) und/oder an der optischen Oberfläche (13a, 14a) auf.