US-20260125304-A1 - APPARATUS AND METHOD FOR THERMALLY TREATING A BODY TO BE THERMALLY TREATED

US20260125304A1US 20260125304 A1US20260125304 A1US 20260125304A1US-20260125304-A1

Abstract

An apparatus ( 100 ) for thermally treating a body ( 101, 102, 103 ) to be thermally treated, in particular for thermally connecting a first partial body ( 101 ) to a second partial body ( 102 ) to form a composite body ( 103 ) at an interface ( 104 ) between the partial bodies. The apparatus also includes a jacket ( 105 ), a temperature-controllable space ( 108 ) within a temperature-control unit ( 106 ) and a heating element ( 109 ), with the jacket contactlessly surrounding the body to be thermally treated before, during and after the thermal treatment. Also disclosed are a method for thermally treating a body to be thermally treated, e.g., for high-temperature bonding of a first partial body to a second partial body ( 102 ) to form a composite body ( 103 ), an optical element ( 609 ), e.g., a reflective optical element, e.g., one ( 609 ) which is temperature-controlled with a channel ( 208 ) through which media flow.

Inventors

Uwe Schellhorn

Assignees

CARL ZEISS SMT GMBH

Dates

Publication Date: 20260507
Application Date: 20260105
Priority Date: 20230706

Claims (20)

1 . A thermal treatment apparatus, comprising: a body to be thermally treated being embodied as a monolithic body, or a composite body, or an arrangement of a first partial body and a second partial body which contact each other at an interface, a jacket, a temperature-controllable space within a temperature-control unit, and one or more heating elements, wherein the jacket contactlessly surrounds the body to be thermally treated before, during and after the thermal treatment and the jacket consists of a same material as the body to be thermally treated.
2 . The apparatus as claimed in claim 1 , wherein an outside of the jacket is cylinder-shaped and has an elliptical shape and a numerical eccentricity ranging between 0.0 and 0.1 in cross section of the cylinder.
3 . The apparatus as claimed in claim 1 , wherein each surface of the jacket is distanced at least 0.1 mm and at most 30 mm from a nearest surface of the body to be thermally treated.
4 . The apparatus as claimed in claim 1 , wherein the body to be thermally treated comprises an amorphous silicon-containing glass and/or a semicrystalline ceramic.
5 . The apparatus as claimed in claim 1 , wherein the body to be thermally treated comprises a titanium-doped quartz glass.
6 . A method for thermally treating a body to be thermally treated with the apparatus as claimed in claim 1 , comprising: providing the body to be thermally treated, arranging the body to be thermally treated and the jacket in the temperature-controllable space such that the jacket contactlessly surrounds the body to be thermally treated, thermally treating the arranged body to be thermally treated and the arranged jacket in the temperature-controllable space.
7 . The method as claimed in claim 6 , wherein said thermally treating comprises: an annealing method and/or a high-temperature bonding method or stack-sealing.
8 . The method as claimed in claim 6 , wherein the body to be thermally treated is formed from amorphous silicon-containing glass and/or from a semicrystalline ceramic.
9 . The method as claimed in claim 6 , wherein the body to be thermally treated is formed from titanium-doped quartz glass.
10 . The method as claimed in claim 6 , wherein said providing of the body to be thermally treated precedes a processing on a surface of the body to be thermally treated by a physical and/or chemical processing method.
11 . The method as claimed in claim 6 , wherein the body to be thermally treated is embodied as the arrangement, and further comprising: forming the interface between the first partial body and the second partial body as a planar interface, a concave or convex interface, a free-form surface.
12 . The method as claimed in claim 11 , wherein said forming of the interface comprises: forming a first structure having a groove and a ridge in a first surface of the first partial body by physical and/or chemical processing, and/or forming a second structure having a groove and a ridge in a second surface of the second partial body by physical and/or chemical processing, and forming at least one continuous channel in an interior of the composite body from the structure situated on the first surface and/or from the structure situated on the second surface when the first partial body and the second partial body are thermally connected to form the composite body.
13 . The method as claimed in claim 12 , further comprising: joining together a plurality of the partial bodies to form the composite body through a stack-sealing method, wherein respective ones of the first partial bodies and the second partial bodies from the plurality of partial bodies contact each other at the interface.
14 . The method as claimed in claim 6 , wherein within the body to be thermally treated a first local temperature of an arbitrary first infinitesimal area element within an arbitrary first sectional plane of a first constant height and a second local temperature of an arbitrary second infinitesimal area element also within the arbitrary first sectional plane of the first constant height differ by no more than 1 K, and the first local temperature and a third local temperature of an arbitrary third infinitesimal area element within an arbitrary second sectional plane of a second constant height have a non-zero temperature difference.
15 . The method as claimed in claim 14 , wherein within the body to be thermally treated starting from the arbitrary first infinitesimal area element with the first local temperature within the arbitrary first sectional plane of the first constant height, a gradient of a first local temperature profile at an arbitrary height, the gradient being along a first normal of the arbitrary first sectional plane of the first constant height toward the arbitrary third infinitesimal area element with the third local temperature within the arbitrary second sectional plane of the second constant height, differs by no more than 5% from an averaged temperature gradient which is calculated over a corresponding temperature profile over an entire height, and starting from the arbitrary second infinitesimal area element with the second local temperature within the arbitrary first sectional plane of the first constant height, a gradient of a second local temperature profile at an arbitrary height, the gradient being along a second normal of the arbitrary first sectional plane of the first constant height toward an arbitrary fourth infinitesimal area element with a fourth local temperature within the arbitrary second sectional plane of the second constant height, differs by no more than 5% from the averaged temperature gradient which is calculated over a corresponding temperature profile over the entire height, wherein the temperature gradient averaged over the first local temperature profile and the temperature gradient averaged over the second local temperature profile differ by no more than 5% from each other.
16 . The method as claimed in claim 6 , further comprising temperature profile phases as follows: a heating phase starting from a first temperature to a second temperature, during which the body to be thermally treated is heated with a temporal heating temperature ramp, a holding phase, during which the body to be thermally treated is held at the second temperature, which is at least approximately time-constant, and a cooling phase starting from the second temperature to the first temperature, during which the body to be thermally treated is cooled with a temporal cooling temperature ramp.
17 . The method as claimed in claim 16 , wherein the body to be thermally treated is embodied as the arrangement, and the first partial body and the second partial body are connected to each other with high-temperature bonding or stack-sealing during the heating phase and/or the holding phase and/or the cooling phase.
18 . The method as claimed in claim 16 , wherein in the body to be thermally treated and the jacket, the cooling temperature ramp is applied with a temporally non-linear profile.
19 . The method as claimed in claim 16 , wherein the cooling temperature ramp comprises a superposition of components as follows: a first component having a continuously falling temperature profile from a first temperature to a second temperature, and a second component having a periodic temperature change starting from a third temperature to a fourth temperature with an amplitude, a period, a phase and an attenuation and/or an amplification.
20 . The method as claimed in claim 19 , wherein within the arbitrary first sectional plane of a first constant height, the cooling temperature ramp generates, at least once, a first spatial temperature profile at an arbitrary first time and, at least once, a second spatial temperature profile at an arbitrary second time, with, at the arbitrary first time or the arbitrary second time, the first local temperature at the first infinitesimal area element being greater than the second local temperature at the second infinitesimal area element, and with the first infinitesimal area element having a smaller distance from the surface than the second infinitesimal area element.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This is a Continuation of International Application PCT/EP2024/065995 which has an international filing date of Jun. 10, 2024, and the disclosure of which is incorporated in its entirety into the present Continuation by reference. This Continuation also claims foreign priority under 35 U.S.C. § 119 (a)-(d) to and also incorporates by reference, in its entirety, German Patent Application DE 10 2023 206 431.6 filed on Jul. 6, 2023. FIELD The invention relates to an apparatus for thermally treating a body to be thermally treated, in particular for thermally connecting a first partial body to a second partial body to form a composite body, further particularly for high-temperature bonding. The invention furthermore relates to a method for thermally treating a body to be thermally treated, in particular for thermally connecting a first partial body to a second partial body to form a composite body, further particularly for high-temperature bonding, at an interface formed between the first partial body and the second partial body. Furthermore, the invention relates to an optical element, in particular a reflective optical element for reflecting extreme ultraviolet (EUV) radiation, furthermore in particular an element temperature-controlled with a channel through which media flow, in particular an element temperature-controlled with a channel through which media flow, further particularly an optical element temperature-controlled with a channel through which media flow, further particularly a reflective optical element temperature-controlled with a channel through which media flow. Furthermore, the invention relates to a semiconductor technology apparatus having at least one optical element, further particularly a reflective optical element which is temperature-controlled by one of the temperature-control devices with a channel, further particularly a projection exposure apparatus for EUV semiconductor lithography or a mask inspection apparatus or a wafer inspection apparatus. BACKGROUND In microlithography, microstructured and nanostructured elements are for example produced as integrated circuits, wherein the structuring properties are defined by irradiation of a substrate with a directed radiation source that for example utilizes light. To this end, use is made of projection exposure apparatuses in particular which inter alia comprise a radiation source, an illumination system, a photomask (known as a reticle) and a projection system. Such partial systems of a projection exposure apparatus are in each case constructed from separate optical units which, starting from a radiation source, initially transmit the radiation used for the lithography via an illumination system to a photomask and which, from there, generate a corresponding image of the photomask on a photosensitive layer of the substrate with the projection system. The photosensitive layer can be a photoresist, and the substrate can be a silicon wafer. In order to be able to generate the smallest possible structures on a substrate with microlithography in projection exposure apparatuses, equipment has been utilized for several years that uses particularly short-wave light from the so-called extreme ultraviolet (EUV) wavelength range with wavelengths between 0.1 nm and 30 nm, in particular 13.5 nm, as radiation. For such radiation, it is not possible to use transmission optics units in a beam path of a projection exposure apparatus consisting of multiple units on account of the inherent radiation absorption of matter in this wavelength range. Therefore, in the case of EUV radiation, only reflection optics units, for example mirrors, are used. In order to continually reduce the structural size of integrated circuits, projection exposure apparatuses that use optical elements with large numerical aperture (high-NA) or with very large numerical aperture (hyper-NA) have recently been proposed or entered production. As the numerical aperture increases, the surface of an optical element required and used to reflect the radiation becomes correspondingly larger. SUMMARY Elements, in particular optical elements, further particularly reflective optical elements, for use in EUV semiconductor lithography in a projection exposure apparatus, e.g. EUV mirrors, need to withstand high thermal loads since the EUV radiation sources in the projection exposure apparatuses for EUV semiconductor lithography emit EUV radiation with high radiant power, and some of this radiant power is absorbed by the reflective coating of the optical element. The thermal energy is accordingly transferred to all elements in direct or indirect contact with the optical element. This effect leads to heating of all elements in direct or indirect contact with the optical element, and these elements may in turn lead to deformations of the optical elements within a projection exposure apparatus for EUV semiconductor lithography. In the beam path of a projection ex