Optical elements and reaction chambers

Abstract

The present invention relates to an optical element (10) for use with a reaction chamber (70), in particular a reaction chamber (70) of a thermal laser evaporation system, the reaction chamber (70) having a chamber wall (72) and a flange (80) of the reaction chamber (70) disposed in an opening (74) in the chamber wall (72). The present invention also relates to a reaction chamber (70), in particular a reaction chamber (70) of a thermal laser evaporation system, comprising a chamber wall (72) enclosing a reaction volume that is sealable, in particular sealable against an ambient atmosphere, the reaction volume being fillable with a reaction atmosphere (90), the reaction chamber (70) further comprising a flange (80) disposed in the opening (74) in the chamber wall (72).

Description

Technical Field

[0001] The present invention relates to an optical element for use with a reaction chamber, particularly a reaction chamber of a thermal laser evaporation system. The reaction chamber has a chamber wall, and a flange of the reaction chamber is disposed at an opening of the chamber wall. Further, the present invention relates to a reaction chamber, particularly a reaction chamber of a thermal laser evaporation system, having a chamber wall that surrounds a reaction volume that can be sealed, particularly sealed against the ambient atmosphere. The reaction volume can be filled with a reaction atmosphere, and the reaction chamber further includes a flange disposed at an opening of the chamber wall.

Background Art

[0002] Applications such as thermal laser epitaxy or synchrotron x-ray optics require active optical surfaces for mirrors, Bragg mirrors, absorbers and the like. FIG. 1 shows such an optical element 10 of the prior art disposed on a flange 80 of a reaction chamber 70. The optical element 10 is disposed at an opening 74 of the chamber wall 72.

[0003] As shown, for the prior art optical element 10, a reflector portion 200 for reflecting or absorbing electromagnetic radiation 100 is made of a first material, while the cooling tube 202 and the seal portion 206 are made of different materials. In the illustrated embodiment, the seal portion 206 forms an elastomer seal, and elastomeric ring seals 84, 88 seal a reaction volume that confines a reaction atmosphere 90 against the outside of the reaction chamber 7 that has an ambient atmosphere 94.

[0004] The use of different materials for the reflector section 200, the cooling tube 22, and the seal section 206, as described above, necessitates fixing these elements to each other, which in the illustrated embodiment is provided by welding 204. However, such joining of dissimilar materials, such as silicon and copper, tends to result in leaks under the high thermal stress imposed by high-power operation, thus requiring expensive non-standard solutions. In addition, due to the welding 204, there is usually no precise mechanical alignment between the seal section 206 and the reflector section 200, and additional measures are required to align the reflector section 200 within the reaction chamber 70.

[0005] In view of the above, an object of the present invention is to provide an improved optical element and an improved reaction chamber for use with a reaction chamber that do not suffer from the aforementioned drawbacks of the state of the art. Specifically, an object of the present invention is to provide an improved optical element and an improved reaction chamber for use with a reaction chamber that simultaneously enable particularly easy placement, especially alignment, of the optical surface of the optical element when it is placed inside the reaction chamber, and reliable sealing of the flange of the reaction chamber in which the optical element can be placed or is placed. [Overview of the project]

[0006] This objective is satisfied by each of the independent patent claims. Specifically, this objective is satisfied by the optical element for use with the reaction chamber described in independent claim 1, and by the reaction chamber described in independent claim 23. Dependent claims describe preferred embodiments of the present invention. Details and advantages described with respect to the optical element according to the first aspect of the present invention also refer to the reaction chamber according to the second aspect of the present invention, and vice versa, where there is technical significance.

[0007] According to a first aspect of the present invention, the objective is satisfied by a reaction chamber, in particular a reaction chamber for a thermal laser evaporation system, the reaction chamber having a chamber wall, and the flange of the reaction chamber being positioned at an opening in the chamber wall.

[0008] An optical element according to a first aspect of the present invention comprises an integrated body having a peripheral end and a chamber end arranged opposite to each other along a central body axis, wherein in the assembled state of the optical element, the peripheral end is located outside the reaction chamber and the chamber end is located inside the reaction chamber. The peripheral end of the body is provided with sealing means for sealing the flange of the reaction chamber, and the chamber end is provided with an optical surface for reflecting and / or shaping and / or absorbing electromagnetic radiation within the reaction chamber.

[0009] An optical element according to a first aspect of the present invention may be used in conjunction with a reaction chamber, and in particular in a flange surrounding an opening in the chamber wall of the reaction chamber. The chamber wall of the reaction chamber encloses a reaction volume that can be sealed to the ambient atmosphere and filled with a reaction atmosphere. The reaction atmosphere is 10 -4 hPa~10 -12 It may be a vacuum of hPa, or a pressure of 10 -8 The apparatus may contain or consist of one or more reaction gases, such as molecular oxygen, ozone, molecular hydrogen, or molecular nitrogen, with a maximum reaction temperature of 1 hPa between hPa and ambient pressure. The reaction gases may also be at least partially ionized, and in particular, they may be ionized by plasma ionization.

[0010] According to the present invention, the core of the optical element is formed by an integrated body. In other words, the integrated body is made of a single material and extends between the peripheral end and the chamber end, with the peripheral end supporting a sealing means and the chamber end supporting an optical surface. Specifically, in the assembled state of the optical element according to the first aspect of the present invention, the peripheral end of the optical element is located outside the reaction chamber, and the chamber end is located inside the reaction chamber, and therefore within the reaction volume.

[0011] The sealing means provided at the periphery end, in cooperation with the respective means of the flange, provide a seal over the opening in the chamber wall. Thus, the reaction atmosphere is contained within the reaction chamber, and the atmosphere present at the periphery end, which is in most cases the ambient atmosphere but is not limited to this, is reliably shut out.

[0012] Correspondingly, the optical surfaces provided at the chamber ends are configured for their intended purpose, namely to reflect and / or shape and / or absorb electromagnetic radiation within the reaction chamber. The electromagnetic radiation according to the present invention may preferably be provided as laser radiation and / or having wavelengths in the UV range and / or the visible range and / or the IR range. However, this list is not limiting, and for example, X-rays or microwaves are also electromagnetic radiation within the scope of the present invention. Such configurations of the optical surfaces may include coatings and / or surface treatments such as polishing or roughening to enhance the reflectivity or absorptivity of the optical surfaces.

[0013] Specifically, the aforementioned peripheral end and chamber end are opposing components of a single, integrated body. In other words, the optical element according to the first aspect of the present invention does not require the assembly of different elements to solve different tasks such as sealing or providing optical properties.

[0014] Furthermore, since the positions and orientations of the peripheral end and the chamber end are fixed relative to each other, aligning the sealing means provided by the peripheral end to the flange of the reaction chamber also determines the position and orientation of the optical surface provided by the chamber end. As a result, additional alignment of the optical surface supported by the chamber end is either not required or at least significantly simplified.

[0015] In summary, by providing an integrated body to the optical element according to the first aspect of the present invention, both tasks, namely sealing the reaction chamber and positioning and aligning the optical surface within the reaction chamber, can be simplified. At the same time, there is no concern about any drawbacks or disadvantages regarding tightness and alignment accuracy.

[0016] Furthermore, an optical element according to the first aspect of the present invention may be characterized in that the main body is made of aluminum, or an aluminum alloy, or copper, or a copper alloy. Both aluminum and copper are elements that have very high reflectivity to electromagnetic radiation. In addition, both materials also have high thermal conductivity, enabling operation under high-intensity electromagnetic radiation. At the same time, both materials are 10 -8 hPa~10 -12 It is suitable for use in high-purity environments, such as reaction atmospheres provided as a vacuum at a pressure of hPa. Using one of the alloys of the material allows for maintaining the aforementioned advantages and improving other characteristics, such as structural stability and / or thermal conductivity. Possible aluminum alloys include, for example, EN AW 6082 T6, a particularly high-strength aluminum alloy, or EN AW 6063, an aluminum alloy with high thermal conductivity exceeding 200 W / mK.

[0017] In addition, an optical element according to a first aspect of the present invention may include a sealing means that forms part of a knife-edge seal, particularly a circumferential knife edge, and / or a ring seal, preferably a circumferential receptacle for a metal ring seal, and / or one or more circumferential sealing surfaces. Preferably, a standardized sealing system such as ISO 3669 may be used. Specifically, a vacuum used as the reaction atmosphere, particularly 10 -8 hPa~10 -12 Knife-edge seals are most suitable for high vacuum pressures of hPa. By providing components for such knife-edge seals, especially all the necessary parts, the safe use of high vacuum as a reaction atmosphere becomes possible.

[0018] Alternatively, an optical element according to a first aspect of the present invention may be characterized in that the sealing means forms part of an elastomer seal, in particular an elastomer ring seal, preferably a circumferential receptacle for an O-ring, and / or one or more circumferential sealing surfaces. Such elastomer seals are one of the most common types of seals used with reaction chambers. By providing components of such elastomer seals, in particular all the necessary components, the optical element according to a first aspect of the present invention can be used with a wide variety of reaction chambers.

[0019] According to another embodiment of the optical element according to the first aspect of the present invention, the chamber end comprises a plane that forms at least a portion of an optical surface that specularly reflects the incident electromagnetic radiation. In other words, in this embodiment, each component of the optical element acts as a plane mirror for electromagnetic radiation, for example, for beam guidance of electromagnetic radiation within the reaction chamber. Thus, precise guidance can be provided in which there is no or at least essentially no dispersion and amplification of electromagnetic radiation within the reaction chamber.

[0020] Additionally or alternatively, an optical element according to a first aspect of the present invention may also be characterized in that the chamber end comprises a curved surface that reflects and shapes incident electromagnetic radiation, preferably focusing and / or defocusing, at least a portion of the optical surface. In other words, in this embodiment, each component of the optical element acts as a shaping element for electromagnetic radiation, for example, for beam guidance of electromagnetic radiation within the reaction chamber. Thus, precise shaping of electromagnetic radiation within the reaction chamber, particularly focusing or defocusing, can be provided.

[0021] According to a further improved embodiment of the optical element according to the first aspect of the present invention, the planar and / or curved surfaces consist of an exposed surface of the body, preferably a polished exposed surface of the body. As described above, aluminum and copper, in particular, already possess high reflectivity to electromagnetic radiation. Therefore, the exposed surface of the integrated body of the optical element according to the first aspect of the present invention can already provide good, or even very good, reflectivity. The reflectivity can be further improved by polishing this exposed surface, for example, using a diamond tool.

[0022] Alternatively, an optical element according to a first aspect of the present invention may also comprise a planar and / or curved surface coated with an active optical coating selected for electromagnetic radiation to be reflected, the active optical coating comprising, in particular, a metallic coating and / or a coating for forming a Bragg mirror as the optical surface. With a metallic coating, the reflectivity of the optical surface can be improved over a wide wavelength range, whereas a Bragg mirror enhances reflectivity only in a very narrow wavelength range and therefore also acts as a filter element. Specifically, the coating may comprise a single-film or multi-film structure, thereby providing adaptation of the optical surface to the specific needs of the intended operation and / or electromagnetic radiation.

[0023] In another alternative embodiment of the optical element according to the first aspect of the present invention, the chamber end comprises a surface covered with a roughened surface and / or an absorbing coating that absorbs incident electromagnetic radiation. In this embodiment, electromagnetic radiation incident on the optical surface should not be reflected, but rather absorbed. This intended absorption can be enhanced by providing a roughened surface and / or an absorbing coating on the optical surface. Roughening can be provided, for example, by sandblasting and / or bead blasting the optical surface.

[0024] The electromagnetic radiation absorbed by the optical surface deposits its energy within the optical surface and thus within the body of the optical element according to the first aspect of the invention. Therefore, by measuring the temperature and / or temperature change of the body, the amount of energy absorbed from the electromagnetic radiation can be determined. In other words, the optical element according to the invention can be used as a bolometer. Based thereon, monitoring of the electromagnetic radiation within the reaction chamber can be provided.

[0025] Furthermore, the optical element according to the first aspect of the invention can be improved by the chamber end being slotted into two or more end segments by slots perpendicular to the body axis, in particular by the two or more end segments being arranged rotationally symmetrically around the body axis. In other words, the optical surface is divided into several parts, namely end segments, each of which comprises one of the parts of the optical surface. Since the slots are separate and isolated from each other on the optical surface, forming end segments, the energy deposition from the absorbed electromagnetic radiation described in the above paragraph also distributes across the end segments. By measuring the temperature and / or temperature change of each of the end segments, the amount of energy absorbed from the electromagnetic radiation in each of these end segments can be determined individually. Based thereon, monitoring of the electromagnetic radiation within the reaction chamber can be provided with improved spatial resolution.

[0026] Preferably, the optical element according to the first aspect of the invention is further improved by the slot extending 5% to 50% of the length of the body along the body axis from the chamber end towards the peripheral end. On the one hand, a slot with a large extension along the body axis provides improved insulation between the end segments, providing a minimum spatial resolution of crosstalk between the end segments with respect to electromagnetic radiation. On the other hand, a slot with a large extension along the body axis also weakens the structural stability of the integral body of the optical element. The extension of the slot along the body axis from the chamber end towards the peripheral end of 5% to 50% of the length of the body is a good trade-off that satisfies both of the aforementioned boundary conditions.

[0027] Further, the optical element according to the first aspect of the present invention may be characterized in that the main body includes one or more continuous cooling ducts for a coolant fluid, and each cooling duct includes an inlet opening and an outlet opening disposed at a peripheral end of the main body. By providing cooling of the integral main body, the optical surface of the optical element according to the first aspect of the present invention can be temperature stabilized, in particular. Since the optical element includes an integral main body as a central portion, this cooling can be provided without the need for additional elements such as cooling pipes. Thereby, continuous conditions in the reaction chamber can be provided for both reflection and absorption of electromagnetic radiation in the optical element according to the first aspect of the present invention.

[0028] Preferably, the optical element according to the first aspect of the present invention can be improved by threading the inlet opening and the outlet opening for the arrangement of the threaded terminals of the coolant fluid supply line. By providing a thread, especially a standardized thread, the connection of the cooling duct of the optical element according to the first aspect of the present invention to other elements of the cooling system can be provided more easily.

[0029] In particular, the optical element according to the first aspect of the present invention may include one or more cooling ducts that are V-shaped, and from each of the inlet opening and the outlet opening, linear legs of the cooling duct extend into the main body, and the two legs meet within the main body. In other words, the two legs of the cooling duct can be easily manufactured as holes, especially deep hole drilling. Thereby, the manufacture of the continuous cooling duct in the integral main body can be simplified.

[0030] The V-shaped cooling water channel has the additional advantage that the sharp direction change of the cooling water at the tip of the cooling duct promotes turbulent flow. Even in the case of a laminar coolant flow, the sharp direction change results in an additional pressure of the cooling water towards the tip of the V-shaped cooling duct. Both effects lead to the disappearance or thinning of the laminar flow layer and thus an increase in the cooling power at this position closest to the center of the optical surface, and in the case of a Gaussian beam, the power density of the electromagnetic radiation is also highest. This increases the efficiency of fluid cooling in this concept.

[0031] In addition, if the optical element according to the first aspect of the present invention is designed to reflect and / or shape the incident electromagnetic radiation on the optical surface, the maximum extending portion of the cooling duct along the body axis may be characterized in that it is at least 60%, preferably 75%, and most preferably 85% or more of the extending portion of the body from the peripheral end to the chamber end along the body axis.

[0032] When used as a reflective element, it is advantageous for the performance of the optical element that the temperature of the reflective optical surface remains constant or at least essentially constant, and is particularly close to the temperature of the coolant fluid. Optimal cooling of the optical surface and, consequently, the aforementioned constant or at least essentially constant, and particularly low, temperature of the optical surface can be provided by providing a cooling duct that terminates near or at least in the vicinity of the optical surface, which can be achieved by ensuring that the maximum extension portion of the cooling duct along the main axis is at least 60%, preferably 75%, and most preferably 85% or more.

[0033] According to an alternative embodiment of the optical element according to a first aspect of the present invention, when the optical surface is designed to absorb incident electromagnetic radiation, the maximum extended portion of the cooling duct along the body axis is 20% to 65%, preferably 35% to 55%, of the extended portion of the body from the peripheral end to the chamber end along the body axis.

[0034] In contrast to the embodiments described in the previous paragraph, when used as an absorbing element, it is advantageous for the performance of the optical element that its absorption capacity and absorption volume are sufficient to absorb the incident electromagnetic radiation. In particular, when the temperature or temperature change of the absorption region of an integrated body is measured to monitor electromagnetic radiation, excessive cooling of the absorption region would be disruptive or even counterproductive. In such a bolometer configuration, the measured temperature is a function of the absorbed power due to finite heat conduction between the measurement point near the absorption surface and the cooling duct. Therefore, a larger distance between the measurement point and the cooling duct, or reduced heat conductivity, for example by reducing the cross-sectional area of ​​the body material between the measurement point and the cooling duct, increases the temperature range for a given absorbed power range and, consequently, increases the sensitivity of the measurement. In addition, by appropriately selecting the coolant fluid temperature, an improved and optimized range of temperature measurement that fits a given temperature range of the temperature sensor can also be provided.

[0035] Therefore, by selecting a cooling duct having a maximum extension portion of 20% to 65%, preferably 35% to 55%, of the extension portion of the body along the body axis from the peripheral end to the chamber end, it can be ensured that sufficient cooling of the integrated body of the optical element can be provided, on the one hand, without interfering with the measurement of energy deposited by absorbed electromagnetic radiation, on the other hand. In other words, in this embodiment, the optical element according to the present invention can act as a bolometer for measuring the energy of absorbed electromagnetic radiation.

[0036] Preferably, the optical element according to the first aspect of the present invention can be further improved by equipping one or more cooling ducts with means for measuring the flow of a coolant fluid and / or means for measuring the absolute temperature of the coolant fluid and / or means for measuring the temperature change of the coolant fluid between an inlet opening and an outlet opening. In this embodiment, the cooling of the optical element itself is used to measure the amount of energy deposited within the integrated body of the optical element. In particular, since the cooling is intended to remove or eliminate the deposited energy, this is a very indirect, but nevertheless very accurate and quantitative method of measuring the amount of energy deposited by incident electromagnetic radiation, especially when the flow rate of the coolant fluid per unit time is also measured in addition to the temperature difference between the inlet and outlet.

[0037] Another alternative or additional embodiment of the optical element according to the first aspect of the present invention is that the body comprises one or more holes for arranging means for measuring the temperature of the body, in particular thermocouples, the one or more holes beginning at the periphery end of the body and ending within the body along the body axis at at least 75%, preferably 85%, most preferably 95% or more of the extended portion of the body along the body axis from the periphery end to the chamber end.

[0038] In contrast to the embodiments described in the preceding paragraph, this embodiment may provide direct measurement of the temperature or temperature change of the integrated body caused by incident electromagnetic radiation. For this purpose, the means for measuring the temperature should be located near or at least near the optical surface. This requirement can be particularly easily met by providing a hole that starts at the peripheral end of the body and ends within the body along the body axis at at least 75%, preferably 85%, and most preferably 95% or more of the extended portion of the body along the body axis from the peripheral end to the chamber end.

[0039] According to a particular embodiment of the optical element according to a first aspect of the present invention, the body is provided with a hole in each of the end segments, each hole terminating within its respective end segment. As described above, the end segments can be used to provide or improve spatial resolution for monitoring electromagnetic radiation incident on an optical surface. For this purpose, measuring the deposited energy for each of the end segments is highly advantageous. Providing a dedicated hole for each end segment, terminating within its respective segment, is a simple but nevertheless effective method for enabling the aforementioned measurements.

[0040] Furthermore, the optical element according to the first aspect of the present invention may be provided with mounting means at the chamber end for attaching and / or securing additional components within the reaction chamber. In other words, in addition to its use as an optical component for reflecting and / or absorbing electromagnetic radiation, the optical element according to the first aspect of the present invention can also be used as a platform for additional components. In particular, precise alignment of the integrated body and optical surface of the optical element according to the first aspect of the present invention for additional components attached and / or secured to the mounting means of the optical element may also be provided.

[0041] In addition, an optical element according to a first aspect of the present invention may be characterized in that the body comprises one or more feedthroughs for providing electrical and / or fluid connections from the peripheral end to the chamber end. An optical element according to a first aspect of the present invention is used to seal an opening in the chamber wall of a reaction chamber. Such an opening may also be used to provide a feedthrough for electrical and / or fluid connections between the reaction volume and the outside of the reaction chamber. By providing this feedthrough with an optical element according to a first aspect of the present invention, some additional openings in the chamber wall of the reaction chamber may be reduced and / or other openings may be used for other purposes.

[0042] According to a preferred improvement of the optical element according to a first aspect of the present invention, one or more feedthroughs terminate at the mounting means to provide electrical and / or fluid connections for additional components that can be positioned and / or fixed to the mounting means. Additional components mounted and / or fixed to the mounting means of the optical element according to a first aspect of the present invention may require electrical and / or fluid connections for their operation. By providing each feedthrough as part of the optical element, the setup of the additional components, and by extension the setup of the entire reaction chamber, can be simplified.

[0043] According to a second aspect of the present invention, the objective is satisfied by a reaction chamber having a chamber wall that encloses a sealable, in particular sealable to an ambient atmosphere, reaction chamber in a thermal laser evaporation system, wherein the reaction volume is fillable with a reaction atmosphere, and the reaction chamber further comprises a flange positioned at an opening in the chamber wall. The reaction chamber according to the second aspect of the present invention is characterized in that the optical element according to the first aspect of the present invention is positioned on the flange and seals the opening in the chamber wall.

[0044] A reaction chamber according to a second aspect of the present invention comprises an optical element according to a first aspect of the present invention. Therefore, a reaction chamber according to a second aspect of the present invention can provide all the advantages described above with respect to the optical element according to a first aspect of the present invention.

[0045] During operation, particularly in reaction chambers used in thermal laser evaporation systems, optical surfaces may be covered by materials evaporated and / or sublimated in the reaction chamber. Therefore, the optical properties of the optical element may change, and in particular, deteriorate. Thus, as a special advantage, since the optical element according to the first aspect of the present invention is positioned in the flange of the reaction chamber according to the second aspect of the present invention, the optical element can be replaced by another, preferably identical, optical element according to the first aspect of the present invention.

[0046] Furthermore, a reaction chamber according to a second aspect of the present invention may include a flange comprising a flange rim for arranging an optical element, wherein the flange rim is connected to the chamber wall by a bellows section. In other words, the flange rim, and by extension the optical element according to the first aspect of the present invention arranged on the flange rim, can be moved slightly because the bellows section can be locally compressed or expanded. This can provide precise alignment and / or correction of the optical element according to the first aspect of the present invention, and by extension the optical surface, within the reaction chamber.

[0047] Furthermore, a reaction chamber according to a second aspect of the present invention may be improved by providing a means for adjusting the relative position of the optical surfaces of the optical elements within the reaction chamber by moving the optical elements within a range of motion provided by a bellows. Such an adjustment means may be, for example, manually driven and / or comprise one or more actuators. This makes it easier to provide the precise alignment and / or correction of the optical surfaces as described above. In addition, the adjustment means may preferably comprise a fixing device for fixing the completed adjustment.

[0048] The present invention will be described in detail below by means of embodiments and with reference to the drawings. The drawings show the following: [Brief explanation of the drawing]

[0049] [Figure 1] This is a schematic side view of optical elements arranged in a reaction chamber according to the level of technology. [Figure 2] This is a schematic side view of a first embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 3] This is a schematic side view of a second embodiment of the optical element according to the present invention. [Figure 4] This is a schematic side view of a third embodiment of the optical element according to the present invention. [Figure 5]This is a schematic side view of a fourth embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 6] This is a schematic side view of a fifth embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 7] This is a schematic side view of a sixth embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 8] This is a schematic side view of a seventh embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 9] This is a schematic side view of an eighth embodiment of an optical element arranged in a reaction chamber according to the present invention. [Figure 10] This is a semi-transparent perspective view of a ninth embodiment of the optical element according to the present invention. [Figure 11] This is a semi-transparent perspective view of a tenth embodiment of the optical element according to the present invention. [Figure 12] This is a semi-transparent perspective view of an eleventh embodiment of the optical element according to the present invention. [Modes for carrying out the invention]

[0050] Figure 2 schematically illustrates one possible embodiment of the optical element 10 according to the present invention, positioned on a flange 80 surrounding an opening 74 in the chamber wall 72 of the reaction chamber 70 according to the present invention. The reaction chamber 70 encloses a reaction volume filled with a reaction atmosphere 90, and outside the reaction chamber 70, there is, in most cases, an ambient atmosphere 94. However, the chamber wall 72 of the reaction chamber 70 can also completely or partially isolate the reaction atmosphere 90 from another atmosphere different from the ambient atmosphere 94.

[0051] As can be clearly seen in Figure 2, the central element of the optical element 10 is an integrated body 12 comprising a peripheral end 30 and a chamber end 40 arranged opposite to each other along the central body axis 14. Preferably, the integrated body 12 is made of aluminum, or an aluminum alloy, or copper, or a copper alloy. In particular, in the arrangement of the optical element shown, the chamber end 40 is located inside the reaction chamber 70, and the peripheral end 30 is located outside the reaction chamber 70.

[0052] Specifically, the peripheral end 30 includes a sealing means 32 for sealing the flange 80 of the reaction chamber 70. In the illustrated example, the sealing means 32 forms an elastomer seal comprising elastomer ring seals 84, 88, the sealing means 32 provides, in particular, a receptacle 36 for the elastomer ring seals 84, 88, and additionally, a sealing surface 38.

[0053] At the opposite end of the integrated body 12, the chamber end 46 supports the optical surface 46. In the illustrated embodiment, the optical surface 46 is further coated with an optical coating 48 to improve reflectivity. This allows for effective reflection of the incident electromagnetic radiation 100. Since the optical surface 46 is provided as a plane, the reflection of the electromagnetic radiation 100 is provided as specular reflection.

[0054] The main advantage of the optical element 10 according to the present invention lies in the fact that the optical element 10 comprises an integrated body 12 that provides both the peripheral end 30 and the chamber end 40 described above. Thereafter, both the sealing means 32 and the optical surface 46 are positioned, located, and oriented in the optical element 10 according to the present invention in a fixed, and in particular, known relationship with respect to each other. Thus, by positioning the sealing means 32 on the flange 80 of the reaction chamber 70 according to the present invention, the position, orientation, and alignment of not only the peripheral end 30 but also the chamber end 40 of the optical element 10 according to the present invention are determined. This makes it possible to avoid additional alignment of the optical surface 46 after placement.

[0055] Several modifications of the embodiment of the optical element 10 are described below. All of these share the inventive concept of an integrated body 12 that includes both the peripheral end 30 and the chamber end 40, and thus share the aforementioned advantages. Accordingly, the differences between each embodiment will be highlighted below in particular. With regard to features shared by different embodiments, the above description, particularly with respect to Figure 2, will be referenced, even if not explicitly mentioned.

[0056] In contrast to the embodiment of the optical element 10 shown in Figure 2, the optical elements 10 in Figures 3 and 4 are intended to absorb incident electromagnetic radiation 100. However, the optical elements 10 in Figures 3 and 4 offer different approaches to enhance their respective absorption capabilities.

[0057] In the embodiment illustrated in Figure 3, the chamber end 40 and, consequently, the optical surface 46 formed on the chamber end 40 are covered with an absorption coating 50. In contrast, Figure 4 shows an optical element 10 having a roughened surface, for example, by sandblasting and / or bead blasting. Although different embodiments are shown, these measures may be combined.

[0058] All other elements of the optical element 10 illustrated in Figures 3 and 4, particularly the integrated body 12 that forms the core of the optical element 10, are configured similarly to those of the embodiment shown in Figure 2. That is, for example, the embodiments of Figures 3 and 4 also include sealing means 32 provided at the peripheral end 30 of the integrated body 12. Therefore, the aforementioned advantage of simplifying the alignment process can still be provided.

[0059] The emphasis of the embodiments of the optical element 10 and reaction chamber 70 according to the present invention shown in Figure 5 lies in the sealing means 32, respectively. Specifically, this sealing means 32 forms part of a knife-edge seal. The circumferential knife edge 34 cuts deeply into the metal ring seals 84, 86 located on the circumferential receptacle 36 of the sealing means 32. The circumferential sealing surface 38 completes the sealing means 32, ensuring a tight seal of the opening 74 in the chamber wall 72 of the reaction chamber 70 (see Figure 2). Specifically, using such a knife-edge seal, the reaction atmosphere 90 inside the reaction chamber 70 is 10 -12 Ultra-high vacuums below hPa can be achieved.

[0060] Here again, for a description of all other elements, in particular the optical surface 46 on the chamber end 40, please refer to the above description of other embodiments of the optical element 10.

[0061] Figure 6 illustrates one embodiment each of the optical element 10 and the reaction chamber 70 according to the present invention, which includes a measuring means 60, in particular a means 60 for measuring the temperature of the integrated body 12. Specifically, this measuring means 60 may be provided as a thermocouple. By measuring the temperature of the body 12, it is possible to measure the energy deposited in the body 12 by electromagnetic radiation 100 incident on the optical surface 46. For this purpose, a hole 16 is provided that starts at the peripheral end 30 and extends into the body 12, and the measuring means 60 is positioned inside the hole 16, preferably at the inner end of the hole 16.

[0062] As shown in Figure 6, for reflected electromagnetic radiation 100, it is advantageous to measure the temperature as close as possible to the optical surface 46. This also applies to reflected electromagnetic radiation 100 (see Figure 11). However, since accidental melting of the chamber end 40 caused by the accumulated energy of electromagnetic radiation 100 cannot be completely eliminated, it was found that an extension of the holes 16 along the main axis 14 of approximately 75% to 95% or more is appropriate.

[0063] Here again, for a description of all other elements, in particular the optical surface 46 on the chamber end 40, please refer to the above description of other embodiments of the optical element 10.

[0064] Figure 7 shows another possible feature of the optical element 10 and the reaction chamber 70 according to the present invention, i.e., equipped with a cooling duct 18 located within a single body 12. The cooling duct 18 extends between an inlet opening 20 and an outlet opening 22, respectively, located at the peripheral end 30 of the body 12. This allows the coolant fluid 92 to flow through the body 12 and remove excess energy resulting from the absorption of electromagnetic radiation 100 incident on the optical surface 46 at the end of the chamber. Preferably, the inlet opening 20 and the outlet opening 22 are threaded for the arrangement of threaded terminals 24 (Figures 11, 12) for the coolant fluid 92 supply line.

[0065] The cooling duct 18, and therefore the optical element 10, may be equipped with means 60 for measuring the flow of the coolant fluid 92, and / or the absolute temperature of the coolant fluid 92, and / or the temperature change of the coolant fluid 92 between the inlet opening 20 and the outlet opening 22. Thus, the amount of cooling, and therefore the amount of energy deposited in the body 12 by the incident electromagnetic radiation 100, can be measured.

[0066] In the embodiment shown in Figure 7, the reflection and / or shaping of electromagnetic radiation 100 on the optical surface 46 is intended. In particular with respect to the temperature of the body 12 near the optical surface 46, in order to provide stable conditions, it is advantageous that the maximum extension portion of the cooling duct 18 along the body axis 14 is at least 60%, preferably 75%, and most preferably 85% or more of the extension portion of the body 12 along the body axis 14 from the peripheral end 30 to the chamber end 40.

[0067] This can be counterproductive, especially for embodiments involving simultaneous temperature measurement of the main body 12 (see Figure 12 and the accompanying description), if the optical surface 46 is designed to absorb the incident electromagnetic radiation 100. Therefore, for these embodiments, the maximum extension of the cooling duct 18 along the main body axis 14 is preferably 20% to 65%, more preferably 35% to 55%, of the extension of the main body 12 from the peripheral end 30 to the chamber end 40 along the main body axis 14, in order to enable sufficient temperature fluctuation and measurement accuracy using the amount of absorbed electromagnetic radiation 100.

[0068] Figure 8 illustrates a further improvement to the reaction chamber 70 according to the present invention. In this embodiment, the flange 80 of the reaction chamber 70 is provided with a flange rim 82 connected to the chamber wall 72 of the reaction chamber 70 by a bellows section 76. The optical element 10 according to the present invention is positioned with its sealing means 32 located on this rim 82.

[0069] As shown in Figure 8, the bellows section 76 allows for some degree of movement of the rim 82 and, consequently, of the optical element 10 positioned and fixed on the rim 82. As a result, alignment of the position and / or orientation of the optical surface 46 on the chamber end 40 of the optical element 10 can be provided more easily by aligning the peripheral end 30 of the optical element 10, and therefore more easily as a whole.

[0070] Specifically, the reaction chamber 70 according to the present invention, for example, the optical element 10, may further include means 78 for adjusting the relative position of the optical surface 46 of the optical element 10 within the reaction chamber 70 by moving the optical element 10 within a range of motion provided by a bellows section 76. This adjustment means 78 may preferably be fixed to the chamber wall 72 and move the peripheral end 30 of the optical element 10 (as shown in Figure 8), or alternatively, the rim 82. The reverse arrangement, in which the adjustment means 78 is fixed to the optical element 10 or the rim 82 and the movable support is fixed to the chamber wall 72, also provides the same advantages.

[0071] In addition, as shown in Figure 9, the optical element 10 and reaction chamber 70 according to the present invention may also be equipped with a feedthrough 64 connecting the chamber end 30 to the surrounding end 40. A sealing means is provided for sealing the opening of the feedthrough 64, but is not shown or referenced in Figure 9, and the feedthrough 64 is used to provide an electrical connection and / or fluid connection from the surrounding end 30 to the chamber end 40.

[0072] In particular, the integrated body 12 may also be provided with mounting means 62 at the chamber end 40 for mounting and / or securing additional components within the reaction chamber 70. In particular, in embodiments having these mounting means 62, each feedthrough 64 may be used to provide the necessary electrical and / or fluid connections for the additional components mounted and / or secured to the mounting means 62.

[0073] Figures 10 to 12 show semi-transmissive perspective views of three different embodiments of the optical element 10 according to the present invention, the first two of which are intended for reflection of electromagnetic radiation 100 at an optical surface 46, and the last one is intended for absorption of electromagnetic radiation 100. All three embodiments of the optical element 10 include a V-shaped cooling duct 18. Two linear legs 26 extend from inlet openings 20 and outlet openings 22, respectively, into the integrated body 12 of each optical element 10, where they meet to form a continuous cooling duct. The embodiments in Figures 11 and 12 further include terminals 24 located at each of the inlet openings 20 and outlet openings 22 for easy and convenient connection of each cooling duct 18 to a coolant fluid 92 supply line.

[0074] In addition, in all three embodiments of the illustrated optical element 10, the sealing means 32 comprises a receptacle 36, a sealing surface 38, and a knife edge 34 of a knife-edge seal.

[0075] Figure 10 shows an optical element 10, whose optical surface 46 is inclined at a particular angle of 45° with respect to the body axis 14 at the chamber end 40. Preferably, the optical element 10 can be used to reflect electromagnetic radiation 100 between a direction parallel to the body axis 14 of the body 12 of the optical element 10 and a direction perpendicular to this body axis 14. The integrated body 12 can preferably be manufactured from a high-strength aluminum alloy such as EN AW 6082 T6. In addition, the optical surface 46 may be machined to a smooth mirror finish using a diamond tool, eliminating the need for further coating.

[0076] In contrast to the embodiments described in the preceding paragraph, Figure 11 shows an optical element 10 having an optical surface 46 perpendicular to the main axis 14 and therefore parallel to the orientation of the flange 80 (not shown; see, for example, Figure 2). This allows for a shorter overall design of the optical element 10 compared to the embodiment with an inclined optical surface 46 described in the preceding paragraph with respect to Figure 10. In addition, the cooling duct 18 can be brought closer to the center of the optical surface 46 and therefore to the point with the highest electromagnetic power density of the incident electromagnetic radiation 100. Furthermore, the higher symmetry of this geometry leads to a more symmetrical temperature distribution on the optical surface 46. This, in turn, reduces the risk of low symmetric distortion of the reflected beam due to non-uniform thermal expansion of the optical surface 46 under high load.

[0077] Figure 12 shows an optical element 10 according to the present invention acting as an absorber with bolometer function. In contrast to the embodiments described with respect to Figures 10 and 11, the optical surface 46 at the chamber end 40 is here roughened by sandblasting or bead blasting to maximize its absorption. The cooling duct 18 terminates around the middle of the portion of the integrated body 12 that extends along the body axis 14, particularly at a significant distance from the optical surface 46. This creates a thermal gradient between the absorbing optical surface 46 and the cooling duct 18 that carries away heat, resulting in a temperature rise even at some distance from the optical surface 46 in the direction of the body axis 14.

[0078] Four long, narrow holes 16 extend into this heating region, allowing for the insertion of narrow temperature measuring means 60 (not shown), preferably thermocouple junctions, at the ends of these four holes 16 to measure the temperature. At the same time, the ends of the holes 16 are far enough away from the absorbing optical surface 46 to provide some safety distance in case of overloading of the optical element 10, which involves melting of the material of the integrated body 12 that is close to the optical surface 46 where the electromagnetic beam is absorbed. The narrow holes 16 are preferably 4 mm in diameter to allow the use of various different temperature sensors.

[0079] Such a setup acts as a bolometer, allowing for the measurement of radiant intensity absorbed through temperatures close to the absorption optical surface 46 while maintaining the peripheral edges 30 of the device at the cooling water temperature. In addition, the absorbed power can be quantitatively determined by measuring the volumetric flow rate per unit time of the coolant fluid 92, in this case the cooling water, and the temperature difference between the coolant fluid 92 at the inlet opening 20 and the outlet opening 22, respectively.

[0080] Furthermore, the illustrated optical element 10 has slots in the optical surface 46 of the chamber end 40, dividing the absorbing optical surface 46 into four end segments 42 of equal size. Each end segment 42 is equipped with a means 60 for measuring temperature located within its own hole 16 at symmetrically equal positions, so that the distribution of absorbed radiant energy among these four end segments 42 can be determined.

[0081] This enables spatially resolved detection of the beam position of the electromagnetic radiation 100 incident on the optical surface 46. The beam is located at the center of the device when equal energy is absorbed in all four end segments 42, and therefore equal temperatures are measured by all four thermocouple sensors 60. Deviations from this equilibrium state provide information about the direction of the deviation, which can therefore be used to steer the beam of electromagnetic radiation 100 and to reposition the beam to the center of the optical element 10. [Explanation of symbols]

[0082] 10 Optical elements 12 Main unit 14 Main shaft 16 holes 18 Cooling duct 20 Entrance opening 22 Exit opening 24 terminals 26 Legs 30 Peripheral end 32 sealing means 34 Knife Edge 36 Receptacles 38 sealing surface 40 Chamber end 42 End segments 44 slots 46 Optical surface 48 Optical Coatings 50 Absorbent Coating 60 Measurement means 62 Mounting means 64 Feedthrough 70 Reaction Chamber 72 Chamber Wall 74 Aperture 76 Bellows 78 Adjustment means 80 flange 82 rim 84 Ring Seals 86 Metal ring seal 88 Elastomer Ring Seals 90 Reaction atmosphere 92 Coolant fluid 94. Surrounding atmosphere 100 Electromagnetic radiation 200 Reflector section 202 Cooling pipe 204 Welding 206 Seal part

Claims

1. A reaction chamber (70) comprising a chamber wall (72) surrounding a sealable reaction volume and a flange (80) positioned at an opening (74) in the chamber wall (72), The reaction volume can be filled with the reaction atmosphere (90), The optical element (10) is positioned on the flange (80) to seal the opening (74) of the chamber wall (72), The optical element (10) comprises an integrated body (12) having peripheral ends (30) and chamber ends (40) arranged opposite to each other along a central body axis (14), In the assembled state of the optical element (10), the peripheral end (30) is located outside the reaction chamber (70), and the chamber end (40) is located inside the reaction chamber (70). The peripheral end (30) of the integrated body (12) is provided with sealing means (32) for sealing the flange (80) of the reaction chamber (70), The chamber end (40) is provided with an optical surface (46) for reflecting and / or shaping and / or absorbing electromagnetic radiation (100) within the reaction chamber (70), The integrated body (12) is provided with one or more holes (16) for arranging means (60) for measuring the temperature of the integrated body (12), A reaction chamber characterized in that the one or more holes (16) begin at the peripheral end (30) of the integrated body (12) and end within the integrated body (12) along the central body axis (14) at least 75% of the extension of the integrated body (12) from the peripheral end (30) toward the chamber end (40) along the central body axis (14).

2. The reaction chamber (70) according to claim 1, characterized in that the integrated body (12) is made of aluminum, or an aluminum alloy, or copper, or a copper alloy.

3. The reaction chamber (70) according to claim 1 or 2, characterized in that the sealing means (32) forms a part of a knife-edge seal and / or a circumferential receptacle (36) for a ring seal (84), and / or one or more circumferential sealing surfaces (38).

4. The reaction chamber (70) according to claim 1 or 2, characterized in that the sealing means (32) forms a part of the elastomer seal and / or one or more circumferential sealing surfaces (38).

5. The reaction chamber (70) according to claim 1, characterized in that the chamber end (40) has a plane that forms at least a portion of the optical surface (46) that specularly reflects the incident electromagnetic radiation (100).

6. The reaction chamber (70) according to claim 5, characterized in that the plane is an exposed surface of the integrated body (12).

7. The reaction chamber (70) according to claim 5, characterized in that the plane is covered with an active optical coating (48) selected for the electromagnetic radiation (100) that is intended to be reflected.

8. The reaction chamber (70) according to claim 1, characterized in that the chamber end (40) has a curved surface that reflects the incident electromagnetic radiation (100) and simultaneously forms at least a portion of the optical surface (46) that shapes it.

9. The reaction chamber (70) according to claim 8, characterized in that the curved surface is an exposed surface of the integrated body (12).

10. The reaction chamber (70) according to claim 8, characterized in that the curved surface is covered with an active optical coating (48) selected for the electromagnetic radiation (100) that is intended to be reflected.

11. The reaction chamber (70) according to claim 1, characterized in that the chamber end (40) has a surface covered with a roughened surface and / or an absorbing coating (50) that absorbs incident electromagnetic radiation (100).

12. The reaction chamber (70) according to claim 11, characterized in that the chamber end (40) is slotted into two or more end segments (42) by slots (44) perpendicular to the central body axis (14).

13. The reaction chamber (70) according to claim 12, characterized in that the slot (44) extends from the chamber end (40) toward the peripheral end (30) along the central body axis (14) for 5% to 50% of the length of the integrated body (12).

14. The integrated body (12) is equipped with one or more continuous cooling ducts (18) for the coolant fluid (92), The reaction chamber (70) according to claim 1, characterized in that each cooling duct (18) is provided with an inlet opening (20) and an outlet opening (22) located at the peripheral end (30) of the integrated body (12).

15. The reaction chamber (70) according to claim 14, characterized in that the inlet opening (20) and the outlet opening (22) are threaded for arranging threaded terminals (24) for supply lines of the coolant fluid (92).

16. The reaction chamber (70) according to claim 14, characterized in that the one or more cooling ducts (18) are V-shaped, and straight legs (26) of the cooling ducts (18) extend into the integrated body (12) from both the inlet opening (20) and the outlet opening (22), and the two legs (26) meet within the integrated body (12).

17. The reaction chamber (70) according to claim 14, wherein the optical surface (46) is designed to reflect and / or shape incident electromagnetic radiation (100), the maximum extending portion of the cooling duct (18) along the central body axis (14) is at least 60% of the extending portion of the integrated body (12) extending along the central body axis (14) from the peripheral end (30) to the chamber end (40).

18. The reaction chamber (70) according to claim 14, wherein the optical surface (46) is designed to absorb incident electromagnetic radiation (100), and the maximum extending portion of the cooling duct (18) along the central body axis (14) is 20% to 65% of the extending portion of the body (12) from the peripheral end (30) to the chamber end (40) along the central body axis (14).

19. The reaction chamber (70) according to claim 14, characterized in that one or more cooling ducts (18) are equipped with means (60) for measuring the flow of the coolant fluid (92), and / or means (60) for measuring the absolute temperature of the coolant fluid (92), and / or means (60) for measuring the temperature change of the coolant fluid (92) between the inlet opening (20) and the outlet opening (22).

20. The reaction chamber (70) according to claim 1, characterized in that the one or more holes (16) terminate within the integrated body (12) along the central body axis (14) at least 85% of the extended portion of the integrated body (12) extending from the peripheral end (30) to the chamber end (40) along the central body axis (14).

21. The integrated body (12) is provided with holes (16) in each of the end segments (42), The reaction chamber (70) according to claim 12, characterized in that each of the holes (16) terminates within each of the end segments (42).

22. The reaction chamber (70) according to claim 1, characterized in that the integrated body (12) is provided with mounting means (62) at its chamber end (40) for attaching and / or fixing additional components within the reaction chamber (70).

23. The reaction chamber (70) according to claim 1, characterized in that the integrated body (12) comprises one or more feedthroughs (64) for providing electrical and / or fluid connections from the peripheral end (30) to the chamber end (40).

24. The integrated body (12) is provided with mounting means (62) at the chamber end (40) for attaching and / or fixing additional components within the reaction chamber (70), The reaction chamber (70) according to claim 23, wherein the one or more feedthroughs (64) terminate at the mounting means (62) to provide electrical and / or fluid connections for the additional components that can be positioned and / or fixed to the mounting means (62).

25. The flange (80) is provided with a flange rim (82) for arranging the optical element (10), The reaction chamber (70) according to claim 1, characterized in that the flange rim (82) is connected to the chamber wall (72) by a bellows section (76).

26. The reaction chamber (70) according to claim 25, further comprising means (78) for adjusting the relative position of the optical surface (46) of the optical element (10) within the reaction chamber (70) by moving the optical element (10) within a range of motion provided by the bellows section (76).

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