Gas analysis device

Abstract

A gas analysis device 100, in order to reduce a moment of force in a gravitational direction with a mounting site or the like as a fulcrum, to suppress an optical axis shift as much as possible, by irradiating a laser to a gas, and detecting the laser transmitted through the gas, thereby analyzing a measured object component contained in the gas, and provided with: a gas cell 1 installed to a pipe H for a gas to flow to introduce the gas; and an optical cell 2 in a long strip shape, connected to the gas cell 1 from a predetermined connection direction X, and housing an optical system 6 supported by a pressure plate 10 in a state of being arranged on an optical path of a laser, the optical cell 2 standing with respect to the connection direction X.

Description

Technical Field

[0001] This invention relates to a gas analysis device. Background Technology

[0002] As a prior gas analysis device, there are known gas analysis devices that use infrared light absorption, as shown in Patent Document 1. The infrared light absorption method analyzes the target components contained in the gas by irradiating the gas introduced into the gas cell with a laser and detecting the laser light passing through the gas.

[0003] Such gas analysis devices have so far been used, for example, to analyze exhaust gases emitted from vehicles. In such applications, they are used, for example, placed in a predetermined location, and therefore, as a device structure, a light source, detector, optical system, etc., are mounted on a pressure plate and housed in a fixed optical unit.

[0004] On the other hand, recently, there has been a need to apply the aforementioned gas analysis device to the analysis of material gases and / or byproduct gases used in, for example, semiconductor manufacturing processes. In such applications, for example, to monitor the state within the process chamber as closely as possible without time lag, gas units are sometimes installed on the piping connected to the process chamber. In this case, the piping layout varies depending on the site conditions, and therefore the orientation of the installed gas analysis device also varies.

[0005] Therefore, as Figure 10 As shown, if the gas unit is mounted on an extending piping system, and the optical unit and / or pressure plate are connected to the gas unit in an inverted position, the following problem arises: The weight of the optical unit generates a torque in the direction of gravity, with the mounting point of the gas unit as the fulcrum. This torque causes the pressure plate to deflect, resulting in a misalignment of the laser's optical axis. This misalignment caused by the torque is not limited to the case where the gas unit is mounted on piping; it is also a common problem when the optical unit and / or pressure plate are mounted at a predetermined location.

[0006] It should be noted that the problems described above are particularly significant when using a multi-reflection unit as the gas element. This is because the incident angle of the laser incident on the gas element in the multi-reflection unit needs to be adjusted to within ±0.1 degrees. The slight optical axis shift caused by the deflection of the pressure plate will cause a decrease in signal intensity, thus compromising analytical accuracy.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2017-187468 Summary of the Invention

[0010] Technical issues

[0011] Therefore, the present invention was made to solve the aforementioned problems, and its main objective is to reduce the torque in the direction of gravity generated by the mounting part or other fulcrums, and to suppress optical axis deviation as much as possible.

[0012] Technical solution

[0013] That is, the gas analysis apparatus of the present invention is characterized in that it analyzes the target component contained in the gas by irradiating the gas with a laser and detecting the laser passing through the gas. The gas analysis apparatus comprises: a gas unit installed in a pipe for supplying the gas to introduce the gas; and an elongated optical unit connected to the gas unit from a predetermined connection direction and housed in an optical system supported by an elongated pressure plate in a state arranged in the optical path of the laser, wherein the optical unit and the pressure plate are erected relative to the connection direction.

[0014] In the case of such a gas analysis device, since the optical unit and pressure plate are erected, and the gas unit is installed on the vertically extending piping, the distance from the mounting point of the gas unit to the center of gravity of the optical unit is shorter compared to the previous structure where the optical unit and pressure plate are flat. This reduces the torque in the direction of gravity generated with the mounting point as the fulcrum, and suppresses optical axis deviation as much as possible.

[0015] Moreover, by making the optical unit stand up, it becomes a configuration of an optical system with a three-dimensional optical path, thus making effective use of the space within the optical unit, thereby achieving miniaturization and / or weight reduction.

[0016] The pressure plate is preferably configured facing the gas unit.

[0017] With this structure, the pressure plate can be placed closer to the gas unit side, thus further reducing the torque in the direction of gravity compared to the previous structure where the pressure plate collapsed.

[0018] Furthermore, the gas analysis apparatus of the present invention is characterized in that it analyzes the target component contained in the gas by irradiating the gas with a laser and detecting the laser passing through the gas. The gas analysis apparatus comprises: a gas unit installed in a pipe for supplying the gas to introduce the gas; and an optical unit connected to the gas unit from a predetermined connection direction and comprising an optical system supported by a pressure plate in a state arranged in the optical path of the laser, wherein the pressure plate is arranged facing the gas unit.

[0019] In the case of such a gas analysis device, the pressure plate and the gas unit are arranged facing each other. In other words, the pressure plate is upright relative to the connection direction between the gas unit and the optical unit. Therefore, for example, when the gas unit is installed on the vertically extending piping, the distance from the installation point of the gas unit to the center of gravity of the optical unit is shortened compared to the previous structure where the pressure plate is tilted. This reduces the torque in the direction of gravity generated with the installation point as the fulcrum and suppresses optical axis deviation as much as possible.

[0020] As an embodiment that more significantly exerts the effects described above, the following configurations can be listed: a light source emitting the laser, a detector detecting the laser, an optical system guiding the laser emitted from the light source to the light-emitting side of the gas unit, and an optical system guiding the laser passing through the gas to the light-receiving side of the detector are supported by the pressure plate.

[0021] With this structure, since many components such as the light source, detector, and various optical systems are supported by the pressure plate, the torque reduction effect obtained by placing the pressure plate on the gas unit side can be more significantly realized.

[0022] Gas analysis devices used in semiconductor manufacturing typically include a heating mechanism for heating a gas cell and / or a heat-insulating component covering the gas cell. In this structure, if the optical unit is to be positioned relative to the gas cell, the gas cell itself is covered by the heat-insulating component, etc. Therefore, it is possible to mount the optical unit on the peripheral components of the gas cell. However, due to the complexity of the peripheral structure of the gas cell, in the mounting configuration described above, there is a risk of accumulated positional offset of the peripheral components leading to optical axis misalignment.

[0023] Therefore, it is preferable that the structure having a heating mechanism for heating the gas unit and a heat insulation member covering the gas unit further includes: a beam member, one end of which is connected to the optical unit, and the other end of which is located inside the heat insulation member and connected to the gas unit, thereby connecting the optical unit and the gas unit.

[0024] With this type of structure, since the optical unit and the gas unit are connected via beam members, even if a structure that allows for temperature regulation of the gas unit is used, the effect of the positional offset of the peripheral components of the gas unit on the optical axis can be minimized as much as possible.

[0025] Furthermore, by placing the beam member between the gas unit and the optical unit, the optical unit and the gas unit can be arranged at a distance, thereby reducing the thermal impact of the gas unit on the optical unit.

[0026] Furthermore, if the optical unit is pre-positioned on the beam member, the optical unit is positioned relative to the gas unit by positioning the beam member relative to the gas unit. This eliminates the need to adjust the optical system even after removing the beam member and optical unit from the gas unit, thus improving maintainability.

[0027] To prevent a reduction in thermal insulation performance caused by the beam member, it is preferable that the beam member has a thermal insulation performance that is at least higher than that of the pressure plate.

[0028] The optical system that guides the laser to the projection side of the gas unit is preferably equipped with at least two reflectors that reflect the laser.

[0029] Thus, since the optical axis of the laser can be adjusted with high precision in the appropriate direction, the incident angle of the laser relative to the gas unit can be set with high precision, and by supporting multiple mirrors with a pressure plate, the torque reduction effect obtained by placing the pressure plate on the gas unit side can be significantly achieved.

[0030] In a structure that includes an adjustment mechanism for adjusting the position or orientation of the optical system, it is preferable that the operating part for operating the adjustment mechanism is on the opposite side of the central part of the optical unit.

[0031] With this structure, the laser's optical axis can be adjusted after the device is assembled. Since the operating part faces the outside of the optical unit, the operation is easy to perform during adjustment.

[0032] If the gas unit has a pair of reflectors inside to reflect the laser multiple times, the torque reduction effect based on the present invention can be more significantly achieved.

[0033] As a more specific implementation, the following configuration can be listed: the gas unit is disposed in a piping connected to a chamber in which a semiconductor manufacturing process is performed.

[0034] To reduce the weight of the optical unit, the gas analysis apparatus preferably includes, in addition to the optical unit, a second optical unit. The second optical unit is connected to the gas unit from a predetermined connection direction and houses an optical system supported by a pressure plate in a state arranged in the optical path of the laser. The pressure plate of the second optical unit is arranged facing the gas unit.

[0035] With this structure, various optical systems can be housed in both the optical unit and the second optical unit, thus reducing the weight of each optical unit.

[0036] Furthermore, the pressure plate of the second optical unit is also arranged facing the gas unit, so the distance from the mounting part of the gas unit to the center of gravity of the second optical unit is shortened, thereby reducing the torque in the direction of gravity generated with the mounting part as the fulcrum.

[0037] Technical effect

[0038] According to the present invention described above, the torque in the direction of gravity generated with the mounting part as a fulcrum can be reduced, and the optical axis offset can be suppressed as much as possible. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a semiconductor manufacturing apparatus that assembles a gas analysis device according to one embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram showing the internal structure of the gas analysis apparatus according to this embodiment.

[0041] Figure 3 This is a schematic diagram showing the internal structure of the optical unit in the gas analysis apparatus of this embodiment.

[0042] Figure 4 This is a schematic diagram showing the overall structure of the gas analysis apparatus according to this embodiment.

[0043] Figure 5 This is a schematic diagram showing the internal structure of a gas analysis apparatus according to another embodiment.

[0044] Figure 6 This is a schematic diagram showing the internal structure of a gas analysis apparatus according to another embodiment.

[0045] Figure 7 This is a schematic diagram illustrating the configuration of the second optical unit in a gas analysis apparatus according to another embodiment.

[0046] Figure 8 This is a schematic diagram showing the structure of a gas analysis apparatus according to another embodiment.

[0047] Figure 9 This is a schematic diagram showing the structure of a gas analysis apparatus according to another embodiment.

[0048] Figure 10 This is a schematic diagram showing the structure of a previous gas analysis device.

[0049] Symbol Explanation

[0050] 100: Gas Analysis Device

[0051] 200: Chamber

[0052] H: Piping

[0053] 1: Gas Unit

[0054] 2: Optical Unit

[0055] 3: Heating mechanism

[0056] 4: Thermal insulation components

[0057] 5: Laser source

[0058] 6: Optical System

[0059] 7: Photodetector

[0060] 8: Signal Processing Department

[0061] 9: Outer shell

[0062] 10: Pressure plate

[0063] 11: Beam components

[0064] F1: Flange

[0065] F2: Flange

[0066] X: Connection direction

[0067] Y: Pipe axis direction

[0068] M: Long side direction

[0069] N: Short side direction Detailed Implementation

[0070] Hereinafter, a gas analysis apparatus according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0071] <Device Structure>

[0072] For example, Figure 1 As shown, the gas analysis apparatus 100 of this embodiment is an apparatus used to be assembled into a semiconductor manufacturing apparatus. It measures the concentration or partial pressure of halides, which are components to be measured, contained in materials gases used in semiconductor manufacturing processes or by-product gases generated by semiconductor manufacturing processes (hereinafter referred to as "gases"). Here, fluorides, chlorides, bromides, etc., can be considered as halides. However, the gas analysis apparatus 100 can also measure components other than halides, and it is not necessary to assemble it into a semiconductor manufacturing apparatus.

[0073] The gas analysis device 100 analyzes the target components in the gas by irradiating it with a laser and detecting the laser light passing through the gas using infrared absorption. Specifically, for example... Figure 1As shown, the gas analysis device 100 includes: a gas unit 1, which introduces gas; and an optical unit 2, which houses various optical systems arranged in the optical path of a laser.

[0074] In this embodiment, the gas unit 1 is a unit that guides gas introduced into or from the chamber 200 where a semiconductor manufacturing process is performed. Here, for example... Figure 1 As shown, the gas unit 1 is installed on a pipe H connected to the exhaust port of the chamber 200. A pressure control valve CV for controlling the pressure of the chamber 200 and a vacuum pump CP for evacuating the chamber 200 are sequentially installed on the pipe H. Furthermore, the gas unit 1 is positioned closer to the chamber 200 than the vacuum pump CP, with its inlet connected upstream of the pressure control valve CV and its outlet connected downstream of the pressure control valve CV. This allows the gas unit 1 to be depressurized to a predetermined pressure lower than atmospheric pressure. However, the configuration of the gas unit 1 is not limited to this; for example, the inlet may also be connected downstream of the pressure control valve CV.

[0075] Specifically, such as Figure 2 As shown, the gas unit 1 has a laser inlet La and an outlet Lb, and is provided with an inlet Pa for introducing gas into the interior and an outlet Pb for discharging gas from the interior. Furthermore, the gas unit 1 is a multi-reflection unit with a pair of reflectors MR inside, performing multiple reflections of the laser. Specifically, in the gas unit 1, a laser beam incident from one of the reflectors MR exits from the same side of the same reflector MR after multiple reflections; in other words, the laser inlet La and outlet Lb are located on the same side.

[0076] In addition, a heating mechanism 3, such as a heater using an electric heating wire, is provided around the gas unit 1 to heat the interior of the gas unit 1 to a predetermined temperature (e.g., 200°C), and a heat insulation member 4, such as a resin, is provided around it in a manner that surrounds the gas unit 1.

[0077] like Figure 2 and Figure 3 As shown, the optical unit 2 includes: a light source 5 that irradiates a laser beam onto the gas unit 1; an optical system 6 disposed in the optical path of the laser beam; a photodetector 7 that detects the laser beam transmitted through the gas; a signal processing unit 8 that uses the light absorption signal obtained from the output signal of the photodetector 7 to calculate the concentration or partial pressure of the component to be measured; and a housing 9 that houses these components. It should be noted that in... Figure 3 In order to explain the internal structure of the optical unit 2, the description of the outer shell 9, etc., is omitted, and is related to... Figure 2 The directions were recorded differently.

[0078] Light source 5 is a laser tube that emits wavelength-modulated laser light, causing laser oscillation, for example, in the mid-infrared range (2.5μm to 25μm). The light source 5 can modulate the oscillation wavelength within a predetermined wavelength modulation range by providing a current (or voltage). It should be noted that other types can be used as long as the oscillation wavelength is variable, and the temperature can also be changed to alter the oscillation wavelength. Furthermore, the light source 5 can be a quantum cascade laser (QCL), a type of semiconductor laser, and is not limited to emitting wavelength-modulated laser light; it can also emit laser light of a specific wavelength. Additionally, the light source 5 can be a light source that emits infrared light or ultraviolet light, or light of various wavelengths. Specifically, it is not limited to laser light sources; various types of light sources can be used, such as thermal light sources, LED light sources, deuterium lamps, xenon lamps, etc. It should be noted that when using the aforementioned multiple reflection unit as the gas unit, the light source 5 should preferably be a light source that emits laser light with high intensity and does not easily attenuate even after multiple reflections.

[0079] The optical system 6 is divided into a projection-side optical system 6 (hereinafter also referred to as projection-side optical system 61) that guides the laser emitted from the light source 5 to the gas unit 1, and a receiving-side optical system 6 (hereinafter also referred to as receiving-side optical system 62) that guides the laser that has passed through the gas unit 1 to the photodetector 7. The projection-side optical system 61 has at least two reflectors that reflect the laser, and the receiving-side optical system 62 has at least two reflectors that reflect the laser. Here, the projection-side optical system 61 has three reflectors, and the receiving-side optical system 62 has two reflectors; specifically, these reflectors are plane mirrors or concave mirrors, etc.

[0080] Furthermore, the optical unit 2 in this embodiment includes an adjustment mechanism 63 for adjusting the position or orientation of the reflector that serves as the optical system 6. Here, the adjustment mechanism 63 is provided in a one-to-one correspondence with the reflector, and the operation part 631 of the adjustment mechanism 63 is configured so that the user operates it in a manner opposite to the central portion of the optical unit 2, that is, in a manner facing outwards and away from the central portion.

[0081] The photodetector 7 here uses a relatively inexpensive thermal detector such as a thermopile, but other types of detectors can also be used, such as quantum optoelectronic elements with good responsiveness, such as HgCdTe, InGaAs, InAsSb, PbSe, etc.

[0082] The signal processing unit 8 includes: analog circuits including buffers, amplifiers, etc.; digital circuits including CPU, memory, etc.; and AD converters, DA converters, etc., which mediate between these analog / digital circuits. The CPU and / or its peripheral devices cooperate according to a predetermined program stored in a predetermined area of ​​the memory, thereby performing the functions of a light source control unit as a control unit for the output of the light source 5 and an arithmetic unit. The arithmetic unit receives the output signal from the photodetector 7 and performs arithmetic processing on the value to calculate the concentration or partial pressure of the component to be measured.

[0083] The outer casing 9 houses the various components described above and is elongated. This is because one or more components, such as the circuit board constituting the signal processing unit 8, are elongated, and thus the optical unit 2 is also elongated. In this embodiment, the outer casing 9 is generally cuboid in shape, and the thickness of one wall along its long side is greater than the thickness of the other walls, thereby functioning as a pressure plate 10 supporting the various components.

[0084] The pressure plate 10 supports at least the optical system 6 positioned in the optical path of the laser, and is a long, flat plate extending along the long side of the optical unit 2. In this embodiment, the pressure plate 10 supports the light-emitting optical system 61 and the light-receiving optical system 62 described above, and also supports the light source 5 and the photodetector 7, thereby supporting most of the total weight of the optical unit 2.

[0085] like Figure 2 and Figure 4 As shown, the optical unit 2 configured in this way is connected to the gas unit 1 from a predetermined connection direction X. More specifically, the connection direction X between the optical unit 2 and the gas unit 1 is a direction that intersects the flow direction Y of the gas introduced into the gas unit 1, i.e., the pipe axis Y of the pipe H connecting the gas unit 1. Here, it is set to be a direction orthogonal to both the gas flow direction Y and the pipe axis Y of the pipe H. That is, in this embodiment, the optical unit 2 is connected from the horizontal direction to the gas unit 1 mounted on the pipe H extending in the vertical direction.

[0086] Furthermore, in this embodiment, the optical unit 2 is erected relative to the connection direction X with the gas unit 1. It should be noted that the state of being erected relative to the connection direction X here refers not only to an upright (orthogonal) state relative to the connection direction X, but also to a state that is slightly tilted from the upright state.

[0087] To explain in more detail, the optical unit 2 is connected to the gas unit 1 in an orientation where its long side direction M intersects the connecting direction X, where the long side direction M and the connecting direction X are orthogonal. Furthermore, in this embodiment, as... Figure 3As shown, the laser tube serving as the light source 5 is arranged along its tube axis in a direction orthogonal to the long side direction M of the optical unit 2, i.e., the short side direction N. In other words, the emission direction of the laser immediately after being emitted from the light source 5 is the short side direction N of the optical unit 2. As the light source 5, various types can be used as described above, so the direction emitted from the light source 5 is not limited to the short side direction N of the optical unit 2.

[0088] In the structure described, the pressure plate 10 is arranged facing the gas unit 1. That is, the pressure plate 10 is positioned closer to the gas unit 1 than the central portion of the optical unit 2 as a whole. In this embodiment, the pressure plate 10 is directly or indirectly connected to the gas unit 1.

[0089] To explain in more detail, such as Figure 2 and Figure 4 As shown, in this embodiment, a beam member 11 connecting the gas unit 1 and the optical unit 2 is interposed between the gas unit 1 and the optical unit 2, and more specifically between the gas unit 1 and the pressure plate 10.

[0090] One end of the beam member 11 is connected to the optical unit 2, and the other end is located inside the heat insulation member 4 and connected to the gas unit 1. More specifically, the flange F2 on the optical unit 2 side, which is one end, is threaded onto the pressure plate 10, and the flange F1 on the gas unit 1 side, which is the other end, is threaded onto the wall of the gas unit 1. Furthermore, a light-passing hole Lc for laser light to pass through is formed inside the beam member 11. Additionally, the beam member 11 has at least higher heat insulation than the pressure plate 10, and is made of the same or different type of resin as the heat insulation member 4, and is provided to penetrate the heat insulation member 4 with its other end located inside the heat insulation member 4.

[0091] <Effects of this implementation method>

[0092] According to the gas analysis apparatus 100 of this embodiment configured in this way, the optical unit 2 is erected relative to the connection direction X, and the pressure plate 10, which accounts for most of the total weight of the optical unit 2, is arranged on the side of the gas unit 1. Therefore, for example, when the gas unit 1 is mounted on the vertically extending pipe H, compared with the previous structure where the optical unit 2 is folded down, the distance from the mounting position of the gas unit 1 to the center of gravity of the optical unit 2 is shortened, thereby reducing the torque in the direction of gravity generated with the mounting position as the fulcrum, and suppressing the optical axis deviation as much as possible.

[0093] In particular, the gas unit 1 in this embodiment is a multi-reflection unit, and the incident angle of the laser incident on the gas unit 1 needs to be adjusted to less than ±0.1 degrees. The optical axis offset of a few micrometers caused by the deflection of the pressure plate 10 will cause signal error, thus making the torque reduction effect mentioned above more significant.

[0094] Furthermore, by making the optical unit 2 stand upright, it becomes an optical system 6 with a three-dimensional optical path, thus effectively utilizing the space within the optical unit 2, thereby achieving miniaturization and / or weight reduction.

[0095] Furthermore, the projection-side optical system 61 includes at least two mirrors, thus allowing the optical axis of the laser to be adjusted with high precision in the appropriate direction, thereby enabling the laser to be set with high precision at the incident angle relative to the gas unit 1.

[0096] Furthermore, since the laser tube 5, which serves as the light source, is arranged with its tube axis along the short side direction N of the optical unit 2, the long side direction M of the optical unit 2 can be made more compact compared to the case where the tube axis is arranged along the long side direction M of the optical unit 2.

[0097] Furthermore, since the adjustment mechanism 63 is included to adjust the position or orientation of the optical system 6, the optical axis of the laser can be adjusted after the device is assembled. The operation part 631 faces the outside of the optical unit 2, so the operability during adjustment is good.

[0098] Furthermore, since it includes a heating mechanism 3 for heating the gas unit 1 and a heat insulation component 4 surrounding the gas unit 1, the temperature of the gas unit 1 can be regulated, thereby preventing, for example, the deterioration of the gas being measured.

[0099] Moreover, as described above, in the structure including the heating mechanism 3 and the heat insulation component 4, if the optical unit is mounted on the peripheral component (e.g., the heat insulation component 4) of the gas unit, the peripheral structure of the gas unit 1 becomes complex, and there is a risk of positional displacement of the peripheral component accumulating and causing optical axis displacement. In this embodiment, the gas unit 1 and the optical unit 2 are connected via the beam component 11. Therefore, even if a structure that can adjust the temperature of the gas unit 1 is adopted, the influence of positional displacement of the peripheral component of the gas unit 1 on the optical axis can be minimized as much as possible.

[0100] Furthermore, by positioning the beam member 11 between the gas unit 1 and the optical unit 2, the optical unit 2 and the gas unit 1 can be arranged at a distance, thereby reducing the thermal impact of the gas unit 1 on the optical unit 2.

[0101] Furthermore, if the optical unit 2 is installed with the beam member 11 pre-positioned, the optical unit 2 is positioned relative to the gas unit 1 by positioning the beam member 11 relative to the gas unit 1. Therefore, even if the beam member 11 and the optical unit 2 are removed from the gas unit 1, there is no need to adjust the optical system 6, thus improving maintainability.

[0102] Furthermore, the beam member 11 has the same thermal insulation properties as the thermal insulation component 4, thus more reliably reducing the thermal impact of the gas unit 1 on the optical unit 2, and also preventing the reduction of thermal insulation properties caused by the beam member 11.

[0103] Furthermore, the larger the cross-sectional area of ​​the beam member 11, the greater the moment of inertia of the cross section, thereby reducing the deflection of the beam member 11 and further reducing the optical axis offset.

[0104] <Other Implementation Methods>

[0105] For example, in the embodiment described above, the gas unit 1 and the optical unit 2 are connected by a single beam member 11, but it can also be as follows: Figure 5 As shown, they are connected by two or more beam members 11.

[0106] Thus, by setting multiple beam members 11, the heat insulation component 4 can be thickened, thereby further ensuring the temperature regulation function.

[0107] Furthermore, as the gas analysis apparatus 100 of the present invention, such as Figure 6 As shown, it is not necessarily necessary to include a temperature regulating mechanism for the gas unit 1. In this case, the heating mechanism 3 and / or heat insulation component 4 in the above embodiment may not be required. In this case, the gas unit 1 and the optical unit 2 may also be directly connected without passing through the beam member 11, etc.

[0108] Furthermore, in the described embodiment, the configuration in which a single optical unit 2 is connected to the gas unit 1 has been explained, but it is also possible to do so as described above. Figure 7 As shown, one or more second optical units 2' are connected to the gas unit 1.

[0109] In other words, the gas analysis device 100 of the present invention may include a second optical unit 2' in addition to the optical unit 2. The second optical unit 2' is connected to the gas unit 1 from a predetermined connection direction and is an optical system supported by the pressure plate 10' in a state of being arranged in the optical path of the laser.

[0110] With this structure, various optical systems can be housed in both the optical unit and the second optical unit, thus reducing the weight of each optical unit.

[0111] Specifically, for example, the following configuration can be listed: one of the optical units 2 or the second optical unit 2' houses the light source 5 and the light-projecting optical system, and the other houses the photodetector 7 and the light-receiving optical system.

[0112] In this case, it is possible to... Figure 7 As shown in (A), the optical unit 2 and the second optical unit 2' are arranged facing each other in a manner that sandwiches the gas unit 1, or as shown in (A). Figure 7 As shown in (B), the optical unit 2 is arranged in a manner that intersects the connection direction between the optical unit 2 and the gas unit 1 and the connection direction between the second optical unit 2' and the gas unit 1.

[0113] In the structure, the pressure plate of the second optical unit 2' is preferably arranged facing the gas unit 1. By means of this arrangement, the distance from the mounting part of the gas unit 1 to the center of gravity of the second optical unit 2' is shortened, thereby reducing the torque in the direction of gravity generated with the mounting part as the fulcrum.

[0114] It should be noted that the specific shape of the second optical unit 2' can be a roughly rectangular strip or a roughly cubic shape. It should also be noted that when the second optical unit 2' is a strip, it is preferable that the second optical unit 2' is also upright relative to the connection direction of the gas unit 1.

[0115] Furthermore, as the gas analysis apparatus 100 of the present invention, such as Figure 8 As shown, multiple light sources 5 can be used, or a single light source 5 (not shown) can be branched using a beam splitter to create multiple optical paths that pass through the gas and are guided to the photodetector 7.

[0116] In this case, for example, one of the optical paths can be made into a long optical path by performing multiple reflections as described in the embodiment, while the other optical path can be made into a short optical path that is shorter than one of the optical paths by performing multiple reflections.

[0117] Furthermore, as the gas analysis apparatus 100 of the present invention, such as Figure 9 As shown in (A), if the pressure plate 10 constituting the optical unit 2 is arranged facing the gas unit 1, the optical unit 2 does not need to be a long strip shape such as, for example, a roughly cubic shape.

[0118] According to this structure, the pressure plate 10 is arranged facing the gas unit 1. In other words, the pressure plate 10 is upright relative to the connection direction X between the gas unit 1 and the optical unit 2. Therefore, for example, when the gas unit is installed on the vertically extending pipe H, the distance from the installation part of the gas unit 1 to the center of gravity of the optical unit 2 is shorter compared to the previous structure where the pressure plate 10 is flat. This reduces the torque in the direction of gravity generated with the installation part as the fulcrum and suppresses optical axis deviation as much as possible.

[0119] In addition, such as Figure 9 As shown in (B), in the gas analysis apparatus 100 of the present invention, if the elongated optical unit 2 is erected relative to the connection direction X with the gas unit 1, the pressure plate 10 is, for example, pre-positioned on the opposite side of the gas unit 1, and does not necessarily need to be facing the gas unit 1.

[0120] In addition, the gas unit 1 can be in various shapes such as approximately cuboid, approximately cubic, or approximately cylindrical, and the gas flow direction and the dimensions (length) along the direction orthogonal to it can also be appropriately changed.

[0121] Furthermore, the gas analysis apparatus 100 of the present invention may, for example, be an analysis apparatus that uses Fourier transform infrared spectroscopy (FTIR), non-dispersive infrared absorption spectroscopy (NDIR), etc.

[0122] In addition, various modifications and / or combinations of embodiments are possible as long as they do not violate the spirit of the present invention.

[0123] Industrial availability

[0124] According to the present invention, the torque in the direction of gravity generated with the mounting part or the like as a fulcrum can be reduced, and optical axis offset can be suppressed as much as possible.

Claims

1. A gas analysis device, characterized in that, The gas analysis apparatus analyzes the target component contained in the gas by irradiating it with a laser and detecting the laser light transmitted through the gas. A gas unit, which is installed in a piping supplying the gas to introduce the gas; and A long, narrow optical unit is connected to the gas unit from a predetermined connection direction, and a reflector supported by a long, narrow pressure plate is housed within the optical path of the laser. The optical unit and the pressure plate are erected relative to the connection direction. The structure, which includes a heating mechanism for heating the gas unit and a heat-insulating member covering the gas unit, further includes: A beam member, one end of which is connected to the optical unit, and the other end located inside the heat insulation component and connected to the gas unit, thereby connecting the optical unit and the gas unit. The pressure plate supports most of the total weight of the optical unit and is positioned closer to the gas unit than the central part of the optical unit as a whole.

2. The gas analysis apparatus according to claim 1, characterized in that, The beam component has a thermal insulation performance that is at least higher than that of the pressure plate.

3. A gas analysis device, characterized in that, The gas analysis apparatus analyzes the target component contained in the gas by irradiating it with a laser and detecting the laser light transmitted through the gas. A gas unit, which is installed in a piping supplying the gas to introduce the gas; and An optical unit is formed by connecting to the gas unit in a predetermined connection direction and housing a reflector supported by a pressure plate in a state arranged in the optical path of the laser. The pressure plate is arranged facing the gas unit. The structure, which includes a heating mechanism for heating the gas unit and a heat-insulating member covering the gas unit, further includes: A beam member, one end of which is connected to the optical unit, and the other end located inside the heat insulation component and connected to the gas unit, thereby connecting the optical unit and the gas unit. The pressure plate supports most of the total weight of the optical unit and is positioned closer to the gas unit than the central part of the optical unit as a whole.

4. The gas analysis apparatus according to claim 1 or 3, characterized in that, The light source emitting the laser, the detector detecting the laser, the reflector guiding the laser emitted from the light source to the projection side of the gas unit, and the reflector guiding the laser passing through the gas to the receiving side of the detector are supported by the pressure plate.

5. The gas analysis apparatus according to claim 1 or 3, characterized in that, The reflector, which guides the laser to the projection side of the gas unit, has at least two reflectors that reflect the laser.

6. The gas analysis apparatus according to claim 1 or 3, characterized in that, In a structure equipped with an adjustment mechanism for adjusting the position or orientation of the reflector, The operating part for operating the adjustment mechanism is located on the opposite side of the central part of the optical unit.

7. The gas analysis apparatus according to claim 1 or 3, characterized in that, The gas unit has a pair of reflectors inside to reflect the laser multiple times.

8. The gas analysis apparatus according to claim 1 or 3, characterized in that, The gas unit is located in a chamber where a semiconductor manufacturing process is carried out or in piping connected to that chamber.

9. The gas analysis apparatus according to claim 1 or 3, characterized in that, In addition to the optical unit, the gas analysis device further includes: a second optical unit, which is connected to the gas unit from a predetermined connection direction and houses a reflector supported by a second pressure plate in a state arranged in the optical path of the laser. The second pressure plate is positioned closer to the gas unit than the central portion of the second optical unit as a whole.

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