Multi-stage biconical multi-gas-port type dynamic gas lock device
By using a multi-stage double-conical pipe configuration and air inlet distribution, the problem of contaminant isolation in extreme ultraviolet lithography machines was solved, enabling clean gas flow and contaminant discharge within the optical aperture channel, thereby improving beam stability and transmittance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-05
- Publication Date
- 2026-04-10
AI Technical Summary
Existing dynamic gas lock devices with a single conical pipe configuration cannot effectively isolate contaminants from the silicon wafer stage chamber and the projection lens chamber in extreme ultraviolet lithography machines. This results in uneven airflow distribution within the aperture channel, an increased probability of contaminants entering the projection lens chamber, and difficulty in improving cleanliness and beam stability.
The device employs a multi-stage double-cone multi-port dynamic gas lock. The optical channel is composed of multi-stage double-cone pipe sections connected in series, with convection and suppression sections. By distributing and adjusting the air inlet and outlet, it ensures that clean gas flows into the chamber quickly and pollutants are discharged, preventing the spread of pollutants.
It improves the transmittance of extreme ultraviolet light and the ability to suppress contaminants, prevents damage to the light aperture channel, ensures stable beam transmission, and meets the cleanliness requirements of the projection lens chamber.
Smart Images
Figure CN121832209A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of extreme ultraviolet lithography technology, and in particular relates to a multi-stage double-cone multi-port dynamic gas lock device. Background Technology
[0002] Extreme ultraviolet (EUV) lithography machines use ultraviolet light with wavelengths of 10 to 14 nanometers as a light source. EUV lithography machines can be used to manufacture chips with advanced processes of 14 nanometers and below. Because EUV light is absorbed by air and most materials, the light source system, projection lens system, and wafer stage system of EUV lithography machines have different vacuum and cleanliness requirements to prevent absorption by contaminants generated during silicon wafer stage processing.
[0003] For silicon wafer chambers, which do not contain optical components, a certain amount of contaminants are allowed. These contaminants are hydrocarbons and water vapor produced by the photochemical reaction of photoresist on the silicon wafer surface under extreme ultraviolet radiation. Therefore, the requirements for clean vacuum are relatively low.
[0004] For projection lens chambers, since they contain reflective optical systems, it is necessary not only to ensure the transmittance of extreme ultraviolet radiation, but also to prevent contaminants that enter through free diffusion from causing carbon deposition and oxidation reactions on the surface of optical elements. Carbon deposition and oxidation reactions will lead to a decrease in the reflectivity of optical elements and a shortened lifespan. Therefore, projection lens chambers must maintain an ultra-clean vacuum environment.
[0005] To transmit the extreme ultraviolet (EUV) beam from the projection lens chamber to the silicon wafer stage chamber, the light source system of an EUV lithography machine is equipped with an aperture channel for the EUV light to pass through. However, due to the different gas environment requirements between the projection lens chamber and the silicon wafer stage chamber, maintaining a vacuum and high cleanliness within the aperture channel, and effectively isolating contaminants from the silicon wafer processing, are key factors affecting the lithography imaging quality and equipment stability.
[0006] To prevent carbon-based contaminants, metal particles, and other volatiles generated in the silicon wafer stage chamber from entering the projection lens chamber, existing dynamic gas lock devices typically employ a single-cone pipe configuration. This involves introducing clean gas at one end of the aperture channel to create a barrier. While this single-cone pipe configuration can mitigate back diffusion of contaminants to some extent, it still faces the following technical bottlenecks: ① The single direction of clean gas introduction easily leads to uneven airflow distribution within the aperture channel, creating backflow and high-pressure zones in the central area. This increases the likelihood of contaminants entering the projection lens chamber and may also scour and damage the aperture channel, causing deformation or even microcracks and the generation of fine particulate contaminants; ② Limited flow field control capabilities make it difficult to further improve the cleanliness of the projection lens chamber; ③ Lack of rapid extraction methods for contaminant gases, making it difficult to promptly remove contaminants already inside the aperture channel, thus affecting the transmittance of extreme ultraviolet light and imaging stability within the aperture channel.
[0007] As extreme ultraviolet (EUV) lithography technology continues to develop towards higher numerical apertures, the cleanliness requirements of EUV lithography machine light source systems are also constantly increasing. For existing dynamic gas lock devices with a single conical pipe configuration, their shortcomings in terms of contaminant suppression efficiency, clean gas utilization efficiency, and stable beam transmission are becoming more prominent. Summary of the Invention
[0008] To address the problems of existing technologies, this invention provides a multi-stage double-cone multi-port dynamic gas lock device. It proposes for the first time a multi-stage double-cone pipe configuration, where the cross-sectional shape of the optical aperture channel is a multi-stage double-cone shape, composed of several double-cone pipe sections connected in series. Each stage of the optical aperture channel is divided into a convection section and a suppression section. The larger end of the convection section faces the projection lens chamber, and the smaller end of the convection section connects with the smaller end of the suppression section to form a narrow throat. The larger end of the suppression section faces the silicon wafer stage chamber. This design ensures that continuously contracting extreme ultraviolet light is transmitted within the optical aperture channel while also ensuring that clean gas introduced through the inlet can quickly flow into the projection lens chamber and the silicon wafer stage chamber, effectively improving the suppression efficiency of contaminants. Through the multi-stage distributed air intakes on the optical aperture channel wall, the clean gas carrying contaminants within the optical aperture channel can be rapidly discharged, meeting the cleanliness requirements of the projection lens chamber and further improving the extreme ultraviolet light transmittance. Simultaneously, it prevents the formation of high-pressure gas zones that could damage the optical aperture channel wall.
[0009] To achieve the above objectives, the present invention adopts the following technical solution: a multi-stage double-cone multi-port dynamic gas lock device, employing a multi-stage double-cone pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is multi-stage double-cone, and it is composed of several double-cone pipe sections connected in series. Each stage of the double-cone pipe section of the optical aperture channel is divided into a convection section and a suppression section. In any single double-cone pipe section, the large end of the convection section faces the projection lens chamber, and the small end of the convection section connects with the small end of the suppression section to form a narrow throat. The large end of the suppression section faces the silicon wafer stage chamber. In any two adjacent double-cone pipe sections, the large end of the convection section and the large end of the suppression section are connected... In the double-conical pipe section adjacent to the projection lens chamber, the large end of the convection section is connected to the projection lens chamber, and at least one row of air inlets is provided on the pipe wall of the convection section along the axial direction; at least one row of air intakes or air inlets is provided on the pipe wall of the suppression section along the axial direction. In the double-conical pipe section adjacent to the silicon wafer stage chamber, the large end of the suppression section is connected to the silicon wafer stage chamber, and at least one row of air inlets is provided on the pipe wall of the suppression section along the axial direction. When the number of double-conical pipe sections is three or more, in any single double-conical pipe section located in the middle position, at least one row of air intakes is provided on the pipe wall of the suppression section along the axial direction.
[0010] In any single double-conical pipe section, the central axis of the air inlet and / or air intake forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle points toward the silicon wafer stage chamber.
[0011] In any single double-conical pipe section, there are multiple air inlets in the same row, which are evenly distributed along the circumference of the pipe wall; there are also multiple air intakes in the same row, which are evenly distributed along the circumference of the pipe wall.
[0012] The number and spacing of air inlets in the same row in the circumferential direction are determined based on the pollutant suppression effectiveness; the number and spacing of air intakes in the same row in the circumferential direction are determined based on the pollutant suppression effectiveness.
[0013] Each air inlet is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas can be a single gas or a mixture of gases.
[0014] Each intake port is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
[0015] The cross-sectional shape of the optical aperture channel is circular or rectangular, and the transition between the inner wall of the optical aperture channel and the air inlet and air outlet is set with rounded or straight chamfers.
[0016] The beneficial effects of this invention are: The multi-stage double-cone multi-port dynamic gas lock device of this invention proposes for the first time a multi-stage double-cone pipe configuration. Specifically, the cross-sectional shape of the optical aperture channel is a multi-stage double-cone shape, composed of several double-cone pipe sections connected in series. Each stage of the double-cone pipe section is divided into a convection section and a suppression section. The larger end of the convection section faces the projection lens chamber, and the smaller end of the convection section connects with the smaller end of the suppression section to form a narrow throat. The larger end of the suppression section faces the silicon wafer stage chamber. This design ensures that continuously shrinking extreme ultraviolet light is transmitted within the optical aperture channel, while also ensuring that clean gas introduced through the air inlet can quickly flow into the projection lens chamber and the silicon wafer stage chamber, effectively improving the suppression efficiency of contaminants. Through the multi-stage distributed air intakes on the optical aperture channel wall, the clean gas carrying contaminants within the optical aperture channel can be rapidly discharged, meeting the cleanliness requirements of the projection lens chamber and further improving the extreme ultraviolet light transmittance. Simultaneously, it prevents the formation of a high-pressure gas zone that could damage the optical aperture channel wall. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of a multi-stage double-cone multi-port dynamic gas lock device according to the present invention (Embodiment 1). Figure 2 This is a schematic diagram of the structure of a multi-stage double-cone multi-port dynamic gas lock device of the present invention (Embodiment 2). Figure 3 This is a schematic diagram of the structure of a multi-stage double-cone multi-port dynamic gas lock device of the present invention (Embodiment 3). Figure 4 This is a schematic diagram of the structure of a multi-stage double-cone multi-port dynamic gas lock device according to the present invention (Example 4). In the diagram, 1—convection section, 2—suppression section, 3—projection lens chamber, 4—silicon wafer stage chamber, 5—air inlet, 6—inhalation port, and 7—narrow throat. Detailed Implementation
[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0019] Example 1
[0020] like Figure 1As shown, a multi-stage double-cone multi-port dynamic gas lock device employs a two-stage double-cone pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is a two-stage double-cone shape, formed by two double-cone pipe sections connected in series. Each stage of the double-cone pipe section of the optical aperture channel is divided into a convection section 1 and a suppression section 2. In any single double-cone pipe section, the larger end of the convection section 1 faces the projection lens chamber 3, and the smaller end of the convection section 1 connects with the smaller end of the suppression section 2 to form a narrow throat 7. The larger end of the suppression section 2 faces the silicon wafer stage chamber 4. In adjacent double-cone pipe sections... In the conical pipe section, the large end of the convection section 1 is connected to the large end of the suppression section 2; in the double conical pipe section adjacent to the projection lens chamber 3, the large end of the convection section 1 is connected to the projection lens chamber, and a row of air inlets 5 is provided on the pipe wall of the convection section 1 along the axial direction, and a row of air intakes 6 is provided on the pipe wall of the suppression section 2 along the axial direction; in the double conical pipe section adjacent to the silicon wafer stage chamber 4, the large end of the suppression section 2 is connected to the silicon wafer stage chamber 4, and a row of air inlets 5 is provided on the pipe wall of the suppression section 2 along the axial direction.
[0021] In any single double-conical pipe section, the central axis of the air inlet 5 and / or the air intake 6 forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle faces the silicon wafer stage chamber 4.
[0022] In any single double-conical pipe section, there are six air inlets 5 in the same row, and the six air inlets 5 are evenly distributed along the circumference of the pipe wall; there are six air intakes 6 in the same row, and the six air intakes 6 are evenly distributed along the circumference of the pipe wall.
[0023] Each air inlet 5 is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas is a mixture of one or more of the following gases: hydrogen, helium, nitrogen, neon, and argon.
[0024] Each air intake 6 is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
[0025] The cross-sectional shape of the light aperture channel is circular, and the transition between the inner wall of the light aperture channel and the air inlet and air intake is rounded.
[0026] Example 2
[0027] like Figure 2As shown, a multi-stage double-cone multi-port dynamic gas lock device adopts a three-stage double-cone pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is a three-stage double-cone shape, and it is composed of three double-cone pipe sections connected in series. Each stage of the double-cone pipe section of the optical aperture channel is divided into a convection section 1 and a suppression section 2. In any single double-cone pipe section, the large end of the convection section 1 faces the projection lens chamber 3, and the small end of the convection section 1 connects with the small end of the suppression section 2 to form a narrow throat 7. The large end of the suppression section 2 faces the silicon wafer stage chamber 4. In any two adjacent double-cone pipe sections, the large end of the convection section 1 and the small end of the suppression section 2 connect to form a narrow throat 7. The large end of section 2 is connected; in the double-conical pipe section adjacent to the projection lens chamber 3, the large end of the convection section 1 is connected to the projection lens chamber, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the convection section 1, and a row of air intakes 6 is arranged along the axial direction on the pipe wall of the suppression section 2; in the double-conical pipe section adjacent to the silicon wafer stage chamber 4, the large end of the suppression section 2 is connected to the silicon wafer stage chamber 4, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the suppression section 2; in the double-conical pipe section located in the middle position, a row of air intakes 6 is arranged along the axial direction on the pipe wall of the suppression section 2.
[0028] In any single double-conical pipe section, the central axis of the air inlet 5 and / or the air intake 6 forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle faces the silicon wafer stage chamber 4.
[0029] In any single double-conical pipe section, there are eight air inlets 5 in the same row, and the eight air inlets 5 are evenly distributed along the circumference of the pipe wall; there are eight air intakes 6 in the same row, and the eight air intakes 6 are evenly distributed along the circumference of the pipe wall.
[0030] Each air inlet 5 is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas is a mixture of one or more of the following gases: hydrogen, helium, nitrogen, neon, and argon.
[0031] Each air intake 6 is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
[0032] The cross-sectional shape of the light aperture channel is rectangular, and the transition between the inner wall of the light aperture channel and the air inlet and air intake is set as a straight chamfer.
[0033] Example 3
[0034] like Figure 3As shown, a multi-stage double-cone multi-port dynamic gas lock device adopts a four-stage double-cone pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is a four-stage double-cone shape, and it is composed of four double-cone pipe sections connected in series. Each stage of the double-cone pipe section of the optical aperture channel is divided into a convection section 1 and a suppression section 2. In any single double-cone pipe section, the large end of the convection section 1 faces the projection lens chamber 3, and the small end of the convection section 1 connects with the small end of the suppression section 2 to form a narrow throat 7. The large end of the suppression section 2 faces the silicon wafer stage chamber 4. In any two adjacent double-cone pipe sections, the large end of the convection section 1 and the small end of the suppression section 2 connect to form a narrow throat 7. The large end of section 2 is connected; in the double-conical pipe section adjacent to the projection lens chamber 3, the large end of the convection section 1 is connected to the projection lens chamber, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the convection section 1, and a row of air intakes 6 is arranged along the axial direction on the pipe wall of the suppression section 2; in the double-conical pipe section adjacent to the silicon wafer stage chamber 4, the large end of the suppression section 2 is connected to the silicon wafer stage chamber 4, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the suppression section 2; in any single double-conical pipe section located in the middle position, a row of air intakes 6 is arranged along the axial direction on the pipe wall of the suppression section 2.
[0035] In any single double-conical pipe section, the central axis of the air inlet 5 and / or the air intake 6 forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle faces the silicon wafer stage chamber 4.
[0036] In any single double-conical pipe section, there are six air inlets 5 in the same row, and the six air inlets 5 are evenly distributed along the circumference of the pipe wall; there are six air intakes 6 in the same row, and the six air intakes 6 are evenly distributed along the circumference of the pipe wall.
[0037] Each air inlet 5 is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas is a mixture of one or more of the following gases: hydrogen, helium, nitrogen, neon, and argon.
[0038] Each air intake 6 is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
[0039] The cross-sectional shape of the light aperture channel is circular, and the transition between the inner wall of the light aperture channel and the air inlet and air intake is rounded.
[0040] Example 4
[0041] like Figure 4As shown, a multi-stage double-cone multi-port dynamic gas lock device adopts a four-stage double-cone pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is a four-stage double-cone shape, and it is composed of four double-cone pipe sections connected in series. Each stage of the double-cone pipe section of the optical aperture channel is divided into a convection section 1 and a suppression section 2. In any single double-cone pipe section, the large end of the convection section 1 faces the projection lens chamber 3, and the small end of the convection section 1 connects with the small end of the suppression section 2 to form a narrow throat 7. The large end of the suppression section 2 faces the silicon wafer stage chamber 4. In any two adjacent double-cone pipe sections, the large end of the convection section 1 and the small end of the suppression section 2 connect to form a narrow throat 7. The large end of section 2 is connected; in the double-conical pipe section adjacent to the projection lens chamber 3, the large end of the convection section 1 is connected to the projection lens chamber, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the convection section 1, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the suppression section 2; in the double-conical pipe section adjacent to the silicon wafer stage chamber 4, the large end of the suppression section 2 is connected to the silicon wafer stage chamber 4, and a row of air inlets 5 is arranged along the axial direction on the pipe wall of the suppression section 2; in any single double-conical pipe section located in the middle position, a row of air intakes 6 is arranged along the axial direction on the pipe wall of the suppression section 2.
[0042] In any single double-conical pipe section, the central axis of the air inlet 5 and / or the air intake 6 forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle faces the silicon wafer stage chamber 4.
[0043] In any single double-conical pipe section, there are eight air inlets 5 in the same row, and the eight air inlets 5 are evenly distributed along the circumference of the pipe wall; there are eight air intakes 6 in the same row, and the eight air intakes 6 are evenly distributed along the circumference of the pipe wall.
[0044] Each air inlet 5 is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas is a mixture of one or more of the following gases: hydrogen, helium, nitrogen, neon, and argon.
[0045] Each air intake 6 is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
[0046] The cross-sectional shape of the light aperture channel is rectangular, and the transition between the inner wall of the light aperture channel and the air inlet and air intake is set as a straight chamfer.
[0047] When the dynamic gas lock device adopts the technical solution of this invention, since the light aperture channel presents a multi-level double cone shape, it exhibits a continuous repeating pattern of contraction followed by expansion from top to bottom. This ensures that the continuously contracting extreme ultraviolet light is transmitted within the light aperture channel. The clean gas input through the air inlet 5 can effectively prevent contaminants from diffusing into the projection lens chamber 3. The negative pressure suction effect of the multi-level air intake 6 can effectively and rapidly discharge the clean gas carrying contaminants from the light aperture channel, meeting the cleanliness requirements of the projection lens chamber 3, preventing a large amount of clean gas from accumulating in the light aperture channel, avoiding the generation of a high-pressure area for gas backflow, and reducing the density of contaminants diffusing into the projection lens chamber 3. This further improves the transmittance of extreme ultraviolet light and the suppression efficiency of contaminants.
[0048] The solutions in the embodiments are not intended to limit the scope of protection of the present invention. All equivalent implementations or modifications that do not depart from the present invention are included in the scope of protection of the present invention.
Claims
1. A multi-stage double-cone multi-port dynamic gas lock device, characterized in that: The system employs a multi-stage biconical pipe configuration. The cross-sectional shape of the optical aperture channel at the center of the pipe is a multi-stage biconical shape, composed of several biconical pipe sections connected in series. Each stage of the biconical pipe section is divided into a convection section and a suppression section. In any single biconical pipe section, the larger end of the convection section faces the projection lens chamber, and the smaller end of the convection section connects with the smaller end of the suppression section to form a narrow throat. The larger end of the suppression section faces the silicon wafer stage chamber. In any two adjacent biconical pipe sections, the larger end of the convection section connects with the larger end of the suppression section. In biconical pipe sections adjacent to the projection lens chamber... The convection section has a large opening that connects to the projection lens chamber. The convection section has at least one row of air inlets along the axial direction on its pipe wall. The suppression section has at least one row of air intakes or air inlets along the axial direction on its pipe wall. In the double-conical pipe section adjacent to the silicon wafer stage chamber, the suppression section has a large opening that connects to the silicon wafer stage chamber. The suppression section has at least one row of air inlets along the axial direction on its pipe wall. When there are three or more double-conical pipe sections, in any single double-conical pipe section located in the middle position, the suppression section has at least one row of air intakes along the axial direction on its pipe wall.
2. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: In any single double-conical pipe section, the central axis of the air inlet and / or air intake forms an acute angle with the central axis of the optical aperture channel, and the tip of the acute angle points toward the silicon wafer stage chamber.
3. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: In any single double-conical pipe section, there are multiple air inlets in the same row, which are evenly distributed along the circumference of the pipe wall; there are also multiple air intakes in the same row, which are evenly distributed along the circumference of the pipe wall.
4. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: The number and spacing of air inlets in the same row in the circumferential direction are determined based on the pollutant suppression effectiveness; the number and spacing of air intakes in the same row in the circumferential direction are determined based on the pollutant suppression effectiveness.
5. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: Each air inlet is independently equipped with a mass flow controller. The flow rate of the clean gas entering the air inlet is adjusted by the mass flow controller. The clean gas can be a single gas or a mixture of gases.
6. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: Each intake port is independently equipped with a vacuum pump unit, which adjusts the pumping speed of the clean gas.
7. The multi-stage double-cone multi-port dynamic gas lock device according to claim 1, characterized in that: The cross-sectional shape of the optical aperture channel is circular or rectangular, and the transition between the inner wall of the optical aperture channel and the air inlet and air outlet is set with rounded or straight chamfers.