Optical path stabilizing control device and photolithography machine

Abstract

The application provides a light path stability control device and a photoetching machine, the light path stability control device comprises an air inlet, a wind baffle, a flow guide grid and a porous component; wherein the air inlet is used for passing in compressed gas; the wind baffle is used for dividing the gas into two paths, the first path of the gas passes through the flow guide grid, and the second path of the gas passes through the porous component; the flow guide grid is used for homogenizing the first path of the gas to dissipate heat for an interferometer; and the porous component is used for homogenizing the second path of the gas to maintain pressure stability of the light path of the interferometer. The light path stability control device provided by the application improves the stability of the light path of the interferometer, and solves the measurement deviation caused by the self-heating of the interferometer, thereby improving the measurement precision of the interferometer.

Description

Technical Field

[0001] This invention relates to the field of lithography machine technology, and in particular to an interferometer optical path stabilization control device and a lithography machine. Background Technology

[0002] As the most precise, advanced, and expensive specialized equipment in the semiconductor industry, lithography machines are subject to particulate contamination and numerous heat sources during operation. The cleanliness of the internal environment and the temperature of the components significantly impact lithography accuracy. Gas baths are a crucial method for suppressing overall contamination and a primary means of temperature and pressure control. Gas bath devices deliver a constant-temperature, constant-pressure airflow to key areas and components such as the workpiece stage, mask stage, wafer transfer device, and interferometer, thereby controlling the space, particle count, and temperature of the components.

[0003] As an instrument for testing optical components and detecting displacement, the interferometer has relatively high requirements for its working environment. According to fluid mechanics theory, fluids generally flow towards regions of lower pressure resistance. This can lead to excessively high flow velocities in the high-speed region of the interferometer's air bath, while the low-speed region often experiences low or no airflow, resulting in reduced stability of the interferometer's optical path. Furthermore, the interferometer generates heat during its tooling operation, which can affect its measurement accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide an optical path stabilization control device and a lithography machine to maintain the stability of the interferometer's optical path, ensure the interferometer's heat dissipation, solve the measurement deviation caused by the interferometer's own heat generation, and improve the interferometer's measurement accuracy.

[0005] To solve the above-mentioned technical problems, the present invention provides an optical path stabilization control device, comprising: an air inlet, a baffle plate, a flow guide grille, and a porous component, wherein,

[0006] The air inlet is used to introduce compressed gas;

[0007] The wind deflector is used to divide the gas into two paths: the first path of gas passes through the flow guide grille, and the second path of gas passes through the porous component.

[0008] The flow guide grille is used to homogenize the first gas stream to dissipate heat from the interferometer;

[0009] The porous component is used to homogenize the second gas path to maintain pressure stability in the interferometer's optical path.

[0010] Optionally, the number of the flow guide grilles is not less than 10, and the angle between the flow guide grilles and the horizontal plane of the cavity they are located is less than 30°.

[0011] Optionally, the number of the flow guide grilles is 11, and the included angle is 25°.

[0012] Optionally, the first gas flows out of the air outlet after passing through the guide grille, the width of the guide grille being equal to the width of the air outlet, and the length of the guide grille being greater than the length of the air outlet.

[0013] Optionally, the flow guide grille is in the form of a plate or a cylinder.

[0014] Optionally, the wind deflector is perpendicular to the horizontal plane of the cavity in which it is located, and the number of wind deflectors is 2, with the height of the first wind deflector closer to the air inlet being greater than the height of the second wind deflector farther away from the air inlet.

[0015] Optionally, the height of the wind deflector is greater than half the height of the cavity in which the wind deflector is located.

[0016] Optionally, the second wind deflector is located at one end edge of the air guide grille away from the air inlet, the first wind deflector is located above the air guide grille, and the length of the first wind deflector is less than the length of the second wind deflector.

[0017] Optionally, the cavity containing the flow guide grille and the cavity containing the porous component form an L-shaped structure.

[0018] Optionally, the porous component is a perforated plate, a filter screen, or a filter cloth; the perforation rate of the perforated plate is not less than 30%.

[0019] Optionally, the optical path stabilization control device further includes a perforated plate, which is disposed above the flow guide grid.

[0020] Optionally, the optical path stabilization control device further includes a high-speed zone grid, which is used to homogenize a portion of the second-path gas that has not passed through the porous assembly to purge the objective lens.

[0021] Optionally, the optical path stabilization control device further includes a perforated plate, which is located between the wind deflector and the porous component, and is used to homogenize the second gas passing through the wind deflector.

[0022] Accordingly, the present invention also provides a lithography machine, which includes the optical path stabilization control device as described above.

[0023] In the optical path stabilization control device and lithography machine provided by the present invention, the baffle plate is used to divide the gas introduced from the air inlet into two paths. The first path of gas is homogenized by the flow guide grid and then used to dissipate heat from the interferometer. The second path of gas is homogenized by the porous component to maintain the pressure stability of the interferometer's optical path, thereby improving the stability of the interferometer's optical path and solving the measurement deviation caused by the interferometer's own heat generation, thus improving the measurement accuracy of the interferometer.

[0024] The cavity containing the flow guide grille and the cavity containing the porous component form an L-shaped structure. The compact cavity design makes the gas flow smoother and avoids the problem of energy dissipation such as eddies caused by excessively large cavities.

[0025] The porous component is a perforated plate. The perforated plate is conducive to uniform airflow in the optical path area of ​​the interferometer and helps to maintain a stable pressure field.

[0026] The porous component is a filter screen or filter cloth. The filter screen or filter cloth helps to increase the pressure resistance at that point, avoids excessive gas purging flow, and avoids insufficient flow at the end (the area where the high-speed zone grid is located).

[0027] A perforated plate is installed on the flow guide grid, which can increase the flow pressure resistance at that point, prevent the purging flow rate from being too large, and prevent the flow rate at the end (the area where the first perforated plate and the high-speed zone grid are located) from being too small. Attached Figure Description

[0028] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention.

[0029] Figure 1 This is a schematic diagram of the optical path stabilization control device provided in Embodiment 1 of the present invention.

[0030] Figure 2 This is a partially enlarged schematic diagram of the optical path stabilization control device provided in Embodiment 1 of the present invention.

[0031] Figure 3 This is a schematic diagram of the gas flow direction inside the optical path stabilization control device provided in Embodiment 1 of the present invention.

[0032] Figure 4 This is a schematic diagram of gas flow lines provided in Embodiment 1 of the present invention.

[0033] Figure 5 This is a wind speed cloud map around the interferometer provided in Embodiment 1 of the present invention.

[0034] Figure 6 This is a cloud map of the air outlet velocity of the perforated plate provided in Embodiment 1 of the present invention.

[0035] Figure 7 This is a partially enlarged schematic diagram of the optical path stabilization control device provided in Embodiment 3 of the present invention. Detailed Implementation

[0036] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0037] As used in this invention, the singular forms “a,” “an,” and “the” include plural objects; the term “or” is generally used to mean “and / or”; the term “a number” is generally used to mean “at least one”; and the term “at least two” is generally used to mean “two or more”. Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature, unless otherwise expressly indicated.

[0038] This invention provides an optical path stabilization control device, comprising: an air inlet, a baffle plate, a flow guide grille, and a porous assembly, wherein,

[0039] The air inlet is used to introduce compressed gas;

[0040] The wind deflector is used to divide the gas into two paths: the first path of gas passes through the flow guide grille, and the second path of gas passes through the porous component.

[0041] The flow guide grille is used to homogenize the first gas stream to dissipate heat from the interferometer;

[0042] The porous component is used to homogenize the second gas path to maintain pressure stability in the interferometer's optical path.

[0043] This invention improves the stability of the interferometer's optical path by incorporating a wind deflector, a flow guide grille, and a porous assembly, and also solves the measurement deviation caused by the interferometer's own heat generation, thereby enhancing the interferometer's measurement accuracy.

[0044] The following is an explanation through specific embodiments.

[0045] Example 1

[0046] Figure 1 This is a schematic diagram of the optical path stabilization control device provided in Embodiment 1 of the present invention. Figure 2 This is a partially enlarged schematic diagram of the optical path stabilization control device provided in Embodiment 1 of the present invention. Please refer to it. Figure 1 and Figure 2As shown, the optical path stabilization control device provided in this embodiment includes: an air inlet 1, a baffle plate 2, a flow guide grille 3, and a porous component 5. The air inlet 1 is used to introduce compressed gas; the baffle plate 2 is used to divide the gas into two paths, with the first path passing through the flow guide grille 3 and the second path passing through the porous component 5; the flow guide grille 3 is used to homogenize the first path of gas to dissipate heat from the interferometer; and the porous component 5 is used to homogenize the second path of gas to maintain pressure stability in the interferometer's optical path.

[0047] In this embodiment, the number of the flow guide grilles 3 is not less than 10, and the flow guide grilles 3 are aligned with the horizontal plane of the cavity they are located on. Figure 1 The angle between the airflow guide grille 3 and the horizontal plane of the cavity is less than 30°. Preferably, the number of the airflow guide grilles 3 is 11, and the angle between the airflow guide grille 3 and the horizontal plane of the cavity is 25°. After the first gas passes through the airflow guide grille 3, it flows out from the air outlet, which is located at the bottom of the airflow guide grille 3. The size of the airflow guide grille 3 is arranged according to the size of the air outlet. Preferably, the width of the airflow guide grille 3 is equal to the width of the air outlet, and the length of the airflow guide grille 3 is greater than the length of the air outlet. More preferably, the length of the airflow guide grille 3 is not less than 11 mm. When the appropriate length, number, and angle of the airflow guide grille 3 are selected, the wind speed angle of the air outlet can remain consistent. The wind speed is determined by the distance between the target object being purged and the purging port. Preferably, the wind speed around the target object is 1.7 m / s.

[0048] In this embodiment, the flow guide grille 3 is plate-shaped or cylindrical, or other shapes known to those skilled in the art.

[0049] The wind deflector 2 is perpendicular to the horizontal plane of the cavity it is located in. In this embodiment, there are two wind deflectors 2. The height of the first wind deflector 21, which is closer to the air inlet 1, is greater than the height of the second wind deflector 22, which is farther from the air inlet 1. The height of each wind deflector 2 is greater than half the height of the cavity in which it is located, and the height of each wind deflector 2 is less than the height of the cavity. The second wind deflector 22 is located at the edge of the guide grille 3 away from the air inlet 1, and the first wind deflector 21 is located above the guide grille 3. The length of the first wind deflector 21 is less than the length of the second wind deflector 22.

[0050] like Figure 1 and Figure 2As shown, the wind deflector 2 and the air guide grille 3 are located in the same cavity. The angle between the air guide grille 3 and the horizontal plane of the cavity is less than 30°. The wind deflector 2 is perpendicular to the horizontal plane of the cavity. Alternatively, the wind deflector 2 can be perpendicular to the air guide grille 3 or have an angle with the air guide grille 3. The second wind deflector 22 is located at the edge of the air guide grille 3 away from the air inlet 1, and the first wind deflector 21 is located above the air guide grille 3.

[0051] In this embodiment, the porous component 5 is preferably a perforated plate. The perforated plate facilitates uniform airflow in the optical path region of the interferometer and helps maintain a stable pressure field. The perforation rate of the perforated plate is not less than 30%.

[0052] The optical path stabilization control device also includes a high-speed zone grid 6, which is used to homogenize a portion of the second-path gas that has not passed through the porous component 5 to purge the objective lens, thereby removing contaminants and reducing the impact of the environment on the objective lens.

[0053] The optical path stabilization control device also includes a perforated plate 4, which is located between the wind deflector 2 and the porous component 4, and is used to homogenize the second gas passing through the wind deflector 2.

[0054] The optical path stabilization control device also includes a housing 7, which surrounds the wind deflector 2, the flow guide grille 3, the waist hole plate 4, the porous component 5, and the high-speed zone grille 6.

[0055] Figure 3 This is a schematic diagram of the gas flow direction inside the optical path stabilization control device provided in Embodiment 1 of the present invention. Figure 4 This is a schematic diagram of the gas streamline provided in Embodiment 1 of the present invention. Please refer to it. Figures 1 to 4As shown, compressed gas (CDA) enters the optical path stabilization control device through the air inlet 1, passes through the baffle plate 2, which changes the direction of the gas and guides its flow. A portion of the gas changes direction toward the interferometer, passes through the flow guide grille 3, and blows onto the interferometer to dissipate heat. This portion of gas is called the first gas path. The flow guide grille 3 serves to homogenize the gas. Another portion of the gas (referred to as the second gas) enters the cavity containing the porous component 5 (a mesh plate in this embodiment) through the perforated plate 4. A portion of this gas (a part of the second gas) is blown towards the optical path of the interferometer after passing through the porous component 5 to maintain the pressure stability of the interferometer's optical path. The area below the porous component 5 is the optical path region of the interferometer, requiring uniform and stable airflow. The porous component 5 plays a role in homogenizing and stabilizing the pressure. Another portion of the gas (another part of the second gas) enters the cavity containing the high-speed zone grid 6 and is blown towards the objective lens through the high-speed zone grid 6 to clean contaminants on the objective lens. The area below the high-speed zone grid 6 is the objective lens region, and the high-speed zone grid 6 plays a role in homogenizing the gas.

[0056] Figure 5 This is a wind speed cloud map around the interferometer provided in Embodiment 1 of the present invention. Figure 6 This is a cloud map of the air outlet velocity of the perforated plate provided in Embodiment 1 of the present invention. Please refer to it. Figure 5 and Figure 6 As shown, under simulation conditions, when the wind speed at the air inlet 1 is set to 12 m / s, there is no air disturbance at the bottom of the optical path stabilization control device. The compressed gas is distributed through the baffle plate 2 to ensure that the flow rate for interferometer purging is greater than or equal to 0.7 m / s. The flow direction is towards the interferometer, and the surrounding wind speed is all higher than 0.7 m / s. The remaining gas continues to flow towards the end. The perforated plate design facilitates uniform airflow in the optical path area and helps maintain a stable pressure field.

[0057] Please continue to refer to this. Figure 1 As shown, the cavity containing the flow guide grille 3 and the cavity containing the porous component 5 form an L-shaped structure. Specifically, the cavity containing the baffle plate 2, the cavity containing the flow guide grille 3, the cavity containing the porous component 5, and the cavity containing the high-speed zone grille 6 form an L-shaped structure. The compact cavity design makes the gas flow smoother and avoids the problem of flow energy dissipation such as eddies caused by excessively large cavities.

[0058] Example 2

[0059] Compared with Embodiment 1, in this embodiment, the porous component 5 is a filter screen or filter cloth. The filter screen or filter cloth can increase the pressure resistance at this location, avoid excessive gas purging flow, and avoid insufficient flow at the end (the area where the high-speed zone grille 6 is located).

[0060] Example 3

[0061] Compared with Embodiment 1, in this embodiment, the optical path stabilization control device further includes a mesh plate 8, such as... Figure 7 As shown, the perforated plate 8 is disposed above the flow guide grid 3. The perforated plate 8 can increase the flow pressure resistance at this location, preventing excessive purging flow and ensuring that the flow at the end (the area where the porous component 5 and the high-speed zone grid 6 are located) is not too low.

[0062] Accordingly, the present invention also provides a lithography machine, which includes the optical path stabilization control device as described above.

[0063] In summary, in the optical path stabilization control device and lithography machine provided by this invention, the baffle plate is used to divide the gas introduced from the air inlet into two paths. The first path of gas is homogenized by the flow guide grid and then used to dissipate heat from the interferometer. The second path of gas is homogenized by the porous component to maintain the pressure stability of the interferometer's optical path, thereby improving the stability of the interferometer's optical path and solving the measurement deviation caused by the interferometer's own heat generation, thus improving the measurement accuracy of the interferometer.

[0064] The cavity containing the flow guide grille and the cavity containing the porous component form an L-shaped structure. The compact cavity design makes the gas flow smoother and avoids the problem of energy dissipation such as eddies caused by excessively large cavities.

[0065] The porous component is a perforated plate. The perforated plate is conducive to uniform airflow in the optical path area of ​​the interferometer and helps to maintain a stable pressure field.

[0066] The porous component is a filter screen or filter cloth. The filter screen or filter cloth helps to increase the pressure resistance at that point, avoids excessive gas purging flow, and avoids insufficient flow at the end (the area where the high-speed zone grid is located).

[0067] A perforated plate is installed on the flow guide grid, which can increase the flow pressure resistance at that point, prevent the purging flow rate from being too large, and prevent the flow rate at the end (the area where the first perforated plate and the high-speed zone grid are located) from being too small.

[0068] It should be noted that the embodiments in this specification are described in a progressive manner. The embodiments described later focus on the differences from the embodiments described earlier. The same and similar parts between the embodiments can be referred to each other.

[0069] Throughout this specification, the phrase "an embodiment" or "this embodiment" indicates that a particular component, structure, or feature described with the embodiment is included in at least one embodiment. Therefore, the phrase "an embodiment" or "this embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, in one or more embodiments, the particular component, structure, or feature may be combined in any suitable manner.

[0070] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. An optical path stabilization control device, characterized in that, include: Air inlet, air deflector, airflow grille, and porous components, among which, The air inlet is used to introduce compressed gas; The wind deflector is used to divide the gas into two paths: the first path of gas passes through the flow guide grille, and the second path of gas passes through the porous component. The flow guide grille is used to homogenize the first gas stream to dissipate heat from the interferometer; The porous component is used to homogenize the second gas path to maintain pressure stability in the interferometer's optical path.

2. The optical path stabilization control device as described in claim 1, characterized in that, The number of flow guide grilles is not less than 10, and the angle between the flow guide grille and the horizontal plane of the cavity it is located is less than 30°.

3. The optical path stabilization control device as described in claim 2, characterized in that, The number of the flow guide grilles is 11, and the included angle is 25°.

4. The optical path stabilization control device as described in claim 3, characterized in that, The first stream of gas flows out of the air outlet after passing through the guide grille. The width of the guide grille is equal to the width of the air outlet, and the length of the guide grille is greater than the length of the air outlet.

5. The optical path stabilization control device as described in claim 4, characterized in that, The flow guide grille is in the shape of a plate or a cylinder.

6. The optical path stabilization control device as described in claim 2, characterized in that, The wind deflector is perpendicular to the horizontal plane of the cavity in which it is located. There are two wind deflectors, and the height of the first wind deflector closer to the air inlet is greater than the height of the second wind deflector farther away from the air inlet.

7. The optical path stabilization control device as described in claim 6, characterized in that, The height of the wind deflector is greater than half the height of the cavity in which the wind deflector is located.

8. The optical path stabilization control device as described in claim 6, characterized in that, The second wind deflector is located at the edge of the air guide grille away from the air inlet, the first wind deflector is located above the air guide grille, and the length of the first wind deflector is less than the length of the second wind deflector.

9. The optical path stabilization control device as described in claim 1, characterized in that, The cavity containing the flow guide grille and the cavity containing the porous component form an L-shaped structure.

10. The optical path stabilization control device as described in claim 1, characterized in that, The porous component is a perforated plate, a filter screen, or a filter cloth; the perforation rate of the perforated plate is not less than 30%.

11. The optical path stabilization control device as described in claim 1, characterized in that, The optical path stabilization control device also includes a perforated plate, which is disposed above the flow guide grid.

12. The optical path stabilization control device as described in claim 1, characterized in that, The optical path stabilization control device also includes a high-speed zone grid, which is used to homogenize a portion of the second-path gas that has not passed through the porous assembly to purge the objective lens.

13. The optical path stabilization control device as described in claim 1, characterized in that, The optical path stabilization control device also includes a perforated plate, which is located between the wind deflector and the porous component, and is used to homogenize the second gas passing through the wind deflector.

14. A lithography machine, characterized in that, Includes the optical path stabilization control device as described in any one of claims 1 to 13.

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