A flexible horizontal moving mirror adjustment device and method for precision instruments

Abstract

The application discloses a flexible horizontal dynamic mirror adjusting device and method for a precision instrument, and belongs to the technical field of precision optical adjustment. The device comprises a lens barrel, a mirror frame, flexible hinges, at least one driving assembly and at least one displacement sensing assembly. The mirror frame is arranged in the interior of the lens barrel through the symmetrical flexible hinges, and the flexible hinges allow the mirror frame to elastically displace in a horizontal plane. The at least one driving assembly is arranged on the lens barrel and used for applying a horizontal driving force to the mirror frame. The at least one displacement sensing assembly is arranged on the lens barrel and used for detecting the displacement amount of the mirror frame in the horizontal plane in real time. The application has the characteristics of compact structure, small parasitic motion, high overall rigidity, high resonance frequency, effective suppression of external vibration interference, compact structure and high rigidity.

Description

Technical Field

[0001] This invention belongs to the field of precision optical adjustment technology, specifically relating to a flexible horizontal moving mirror adjustment device and method for precision instruments. Background Technology

[0002] Photolithography machines are core equipment in semiconductor manufacturing, and their resolution directly determines the linewidth of integrated circuits. The projection lithography objective lens, as the heart of the lithography machine, is crucial for its imaging quality. During the assembly, adjustment, and use of the lithography objective lens, factors such as assembly errors, temperature changes, and stress release can cause slight shifts in the lens position, leading to increased aberrations and affecting image quality. Therefore, precise online adjustment of the lens position is necessary to compensate for these aberrations.

[0003] Existing lens adjustment solutions mostly employ friction-based macro / micro actuation or direct piezoelectric ceramic actuation. The former suffers from nonlinearity, creeping, and backlash issues, making it difficult to achieve nanometer-level stable positioning; the latter, while offering high resolution, has a short stroke and exhibits hysteresis and creep, requiring complex control algorithms for compensation.

[0004] Therefore, there is an urgent need for a moving mirror displacement adjustment scheme that can achieve large stroke, high precision, high stability and compact structure, to solve the related requirements of large stroke, high resolution and precision of the moving mirror in the adjustment of lithography objectives. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A flexible horizontal moving mirror adjustment device for precision instruments includes: a mirror barrel, a mirror frame, a flexible hinge, at least one drive component, and at least one displacement sensing component.

[0007] The lens frame is disposed inside the lens barrel by symmetrically arranged flexible hinges, which allow the lens frame to undergo elastic displacement in the horizontal plane; at least one drive component is disposed on the lens barrel for applying a horizontal driving force to the lens frame; at least one displacement sensing component is disposed on the lens barrel for detecting the amount of displacement of the lens frame in the horizontal plane in real time.

[0008] A method for adjusting a flexible horizontal moving mirror for a precision instrument, used in the aforementioned flexible horizontal moving mirror adjustment device for a precision instrument, includes: receiving a displacement adjustment command from an external control system.

[0009] The motor is driven to move according to the displacement adjustment command, and a horizontal thrust is applied to the flexible hinge through the push rod;

[0010] The flexible hinge undergoes elastic deformation under horizontal thrust, causing the frame to move and thus the lens to move horizontally.

[0011] The actual displacement of the lens is monitored in real time by a capacitive sensor, and the monitoring data is fed back to the external control system.

[0012] The external control system compares the actual displacement with the target displacement and adjusts the motor drive signal until the error between the actual displacement and the target displacement is within the allowable range, thereby achieving control of the lens displacement.

[0013] The present invention has the following beneficial effects:

[0014] (1) By adopting flexible hinge transmission, the present invention achieves frictionless and backlash-free motion characteristics, smooth motion and high resolution; combined with closed-loop control with feedback from capacitive sensor, the effects of temperature drift and hysteresis are eliminated, thereby achieving nanometer-level positioning stability and repeatability.

[0015] (2) By using a motor drive, the present invention achieves a working stroke at the millimeter level, which can better meet the needs of large-range aberration compensation of lithography objectives compared with the pure piezoelectric drive method.

[0016] (3) The present invention adopts an integrated flexible mechanism with a compact structure and small parasitic motion; at the same time, it has high overall stiffness and high resonant frequency, which can effectively suppress external vibration interference, and has the characteristics of compact structure and high rigidity. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the flexible horizontal moving mirror adjustment device for precision instruments according to the present invention, wherein 1-mirror tube, 2-mirror frame, 3-flexible hinge, 4-motor, 5-push rod, 6-capacitive sensor, 7-top rod, 8-pin;

[0018] Figure 2 This is an axial cross-sectional view of the flexible horizontal moving mirror adjustment device for precision instruments of the present invention, wherein 4-motor, 5-push rod, 6-capacitive sensor, 9-pressure ring, 10-sensor feedback rod, 11-bullseye bearing, 12-lens;

[0019] Figure 3 This is a partially enlarged view of the flexible hinge of the flexible horizontal moving mirror adjustment device for precision instruments according to the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0021] The flexible horizontal moving mirror adjustment device for precision instruments provided by the present invention achieves large-stroke, high-precision, frictionless, and low-backlash displacement adjustment of the flexible horizontal moving mirror in the horizontal plane by driving a flexible hinge 3 with a motor 4. To achieve the above functions, the flexible horizontal moving mirror adjustment device for precision instruments of the present invention includes a mirror tube 1, a mirror frame 2, a flexible hinge 3, a drive assembly, and a displacement sensing assembly.

[0022] The frame 2 is set inside the lens barrel 1 by at least two symmetrically arranged flexible hinges 3, forming a flexible support structure.

[0023] The drive assembly includes a motor 4 and a push rod 5. The motor 4 is fixed to the outer wall of the lens barrel 1, and the push rod 5 acts on the side of the lens frame 2 under the drive of the motor 4.

[0024] The displacement sensing component includes a capacitive sensor 6, which is fixed to the lens barrel 1 and faces the sensor feedback rod on the side of the lens frame 2.

[0025] Preferably, the flexible hinge 3 and the lens barrel 1 adopt an integral structure and are processed from the same piece of material by wire cutting process, which eliminates the connection gap and improves rigidity and stability. If subsequent processes and assembly requirements are met, it can be set as a split structure.

[0026] Preferably, motor 4 is a piezoelectric motor or a high-precision push rod motor. The former can provide high resolution and self-locking capability, while the latter can provide large stroke and smooth movement.

[0027] Preferably, the frame 2 and the lens barrel 1 are initially angularly positioned by a pin to ensure assembly accuracy.

[0028] like Figure 1 , Figure 2 As shown, the present invention provides a flexible horizontal moving mirror adjustment device for precision instruments, comprising: a mirror tube 1, a mirror frame 2, a flexible hinge 3, at least one driving component and at least one displacement sensing component;

[0029] The frame 2 is installed inside the lens barrel 1 by symmetrically arranged flexible hinges 3, which allow the frame 2 to undergo elastic displacement in the horizontal plane.

[0030] At least one drive component is disposed on the lens barrel 1 for applying a horizontal driving force to the flexible hinge 3;

[0031] At least one displacement sensing component is disposed on the lens barrel 1 for real-time detection of the displacement of the lens frame 2 in the horizontal plane.

[0032] The driver components include:

[0033] Motor 4 is a push rod type motor;

[0034] The bullseye bearing 11 is connected to the flexible hinge 3 via a threaded connection to the part of the flexible hinge 3 that has flexible motion properties.

[0035] The push rod 5 has one end connected to the output shaft of the motor 4, and the other end in contact with the bullseye bearing 11 located on the side connector of the flexible hinge 3.

[0036] The push rod 7 is fixed to the flexible hinge 3 by a threaded connection and is used to lock the drive assembly after it has been positioned.

[0037] The sensor feedback rod 10 is positioned symmetrically to the push rod 5 and is fixed to the flexible hinge 3 via a threaded connection, providing a monitoring reference for the capacitive sensor 6.

[0038] The displacement sensing component includes a capacitive sensor 6, which is fixed to the lens barrel 1. Its probe faces the sensor feedback rod 10 set on the side of the lens frame 2 to measure the gap change in a non-contact manner.

[0039] like Figure 1 , Figure 3 As shown, the flexible hinge 3 adopts a single-axis or dual-axis structure and is integrally formed by wire cutting process. The specific structural forms include straight, arc or elliptical.

[0040] The frame 2 and the flexible hinge 3 are circumferentially positioned by a pin 8. After the positioning and fixing are completed, the flexible hinge 3 is fixed to the bottom of the lens barrel 1 by a threaded connection.

[0041] It also includes a pressure ring 9 fixed to the flexible hinge 3 by a threaded connection, used to press the lens 12 into the lens mount of the frame 2 from the axial direction.

[0042] The present invention further provides a method for adjusting a flexible horizontal moving mirror for precision instruments, comprising the following steps:

[0043] Receive displacement adjustment commands from an external control system;

[0044] According to the displacement adjustment command, the drive motor 4 is activated, and the push rod 5 applies a horizontal thrust to the flexible hinge 3.

[0045] The flexible hinge 3 undergoes elastic deformation under the action of horizontal thrust, which drives the mirror frame 2 to move, thereby causing the flexible horizontal moving mirror to produce horizontal displacement.

[0046] The actual displacement of the flexible horizontal moving mirror is monitored in real time by the capacitive sensor 6, and the monitoring data is fed back to the external control system.

[0047] The external control system compares the actual displacement with the target displacement and adjusts the drive signal of motor 4 until the error between the actual displacement and the target displacement is within the allowable range, thereby achieving closed-loop control of the lens's 12-micron sub-micron displacement.

[0048] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0049] The flexible horizontal moving mirror adjustment device for precision instruments of the present invention, such as Figure 1 , Figure 2 As shown, it includes: lens barrel 1, lens frame 2, flexible hinge 3, motor 4, push rod 5, capacitive sensor 6, push rod 7, as well as pin 8, pressure ring 9, sensor feedback rod 10, bullseye bearing 11, and lens 12.

[0050] The frame 2 is connected to the flexible hinge 3 by screws and suspended inside the lens barrel 1. The lens 12 is pressed into the lens mount of the frame 2 by the pressure ring 9.

[0051] During assembly, the relative angular positions of the frame 2 and the flexible hinge 3 are first determined by the pin 8, and then the flexible hinge 3 and the lens barrel 1 are connected and fixed by screws, with additional pins 8 used for positioning.

[0052] The drive assembly uses a push rod motor 4, which is fixed to the outer wall of the lens barrel 1 by a bracket. The output shaft of the motor 4 is connected to a push rod 5, and the end of the push rod 5 rests on a bullseye bearing 11 fixed to the connecting piece on the side of the flexible hinge 3. When the external control system issues a command, the motor 4 drives the push rod 5 forward or backward, thereby applying a horizontal thrust to the lens frame 2.

[0053] The capacitive sensor 6 is fixed to the lens barrel 1 by another bracket. Its probe is directly facing the precision-polished measurement area of ​​the side adapter rod of the flexible hinge 3. It is used to detect the absolute displacement of the flexible hinge 3 in the horizontal direction in real time, thereby detecting the absolute displacement of the lens frame 2 in the horizontal direction in real time.

[0054] During operation, the external control system calculates the target displacement required for the flexible horizontal moving mirror based on the aberration detection results. Subsequently, a drive signal is applied to the push rod motor 4, which pushes the push rod 5. The thrust is transmitted to the mirror frame 2 through the bullseye bearing 11, causing the flexible hinge 3 to elastically deform, thereby driving the mirror frame 2 to produce the required horizontal displacement. A capacitive sensor 6 monitors the actual displacement of the mirror frame 2 in real time and feeds the measured displacement signal back to the external control system. Based on the deviation between the target displacement and the actual displacement, the control system uses a high-precision control algorithm to adjust the drive signal of the motor 4 in real time, forming a high-precision closed-loop control circuit until the displacement error between the actual and target displacements converges to within the sub-micron level, thus accurately compensating for the image aberration of the photolithographic object.

[0055] The above description is merely an embodiment of the present invention and does not limit the scope of the invention. Any equivalent structural or procedural transformations made based on the description and drawings of this invention, or direct or indirect applications in other related system fields, are similarly included within the protection scope of this invention. Contents not described in detail in this specification are prior art known to those skilled in the art.

Claims

1. A flexible horizontal moving mirror adjustment device for precision instruments, characterized in that, include: The lens barrel, the lens frame, the flexible hinge, at least one drive component, and at least one displacement sensing component; The lens frame is disposed inside the lens barrel by symmetrically arranged flexible hinges, which allow the lens frame to undergo elastic displacement in the horizontal plane; at least one drive component is disposed on the lens barrel for applying a horizontal driving force to the lens frame; at least one displacement sensing component is disposed on the lens barrel for detecting the amount of displacement of the lens frame in the horizontal plane in real time.

2. The flexible horizontal moving mirror adjustment device for precision instruments according to claim 1, characterized in that, The driver components include: The motor is configured as a push rod type motor; The push rod has one end connected to the output shaft of the motor and the other end resting on the bullseye bearing set on the side connector of the flexible hinge. The bullseye bearing is connected to a flexible hinge, which transmits horizontal thrust to the frame.

3. The flexible horizontal moving mirror adjustment device for precision instruments according to claim 1, characterized in that, The displacement sensing component includes: A capacitive sensor is fixed on the lens barrel, with its probe facing the sensor feedback rod located symmetrically to the push rod, to measure gap changes in a non-contact manner.

4. The flexible horizontal moving mirror adjustment device for precision instruments according to claim 1, characterized in that, The flexible hinge and the lens barrel are integrated into one piece, and are formed from the same material by wire cutting. The flexible hinge adopts a single-axis or dual-axis structure, and the specific structural forms include straight, arc or elliptical.

5. The flexible horizontal moving mirror adjustment device for precision instruments according to claim 1, characterized in that, The frame and the flexible hinge are initially angularly positioned by a pin, and the flexible hinge is fixed to the bottom of the lens barrel.

6. The flexible horizontal moving mirror adjustment device for precision instruments according to claim 1, characterized in that, It also includes a pressure ring, which is fixed to a flexible hinge and used to press the lens into the lens mount of the frame from the axial direction.

7. A method for adjusting a flexible horizontal moving mirror for a precision instrument, used in any one of the flexible horizontal moving mirror adjustment devices for precision instruments as described in claims 1 to 6, characterized in that, include: Receive displacement adjustment commands from an external control system; The motor is driven to move according to the displacement adjustment command, and a horizontal thrust is applied to the flexible hinge through the push rod; The flexible hinge undergoes elastic deformation under horizontal thrust, which drives the frame to move, thereby causing the lens to shift horizontally. The actual displacement of the lens is monitored in real time by a capacitive sensor, and the monitoring data is fed back to the external control system. The external control system compares the actual displacement with the target displacement and adjusts the motor drive signal until the error between the actual displacement and the target displacement is within the allowable range, thereby achieving control of the lens displacement.

8. The method for adjusting a flexible horizontal moving mirror for precision instruments according to claim 7, characterized in that, The motor is a push rod type motor. The output shaft of the motor is connected to the push rod, and the end of the push rod rests on the bullseye bearing set on the side connector of the flexible hinge. The motor transmits horizontal thrust to the frame through the push rod and the bullseye bearing.

9. The method for adjusting a flexible horizontal moving mirror for precision instruments according to claim 7, characterized in that, The probe of the capacitive sensor is positioned directly opposite the sensor feedback rod, which is symmetrical to the push rod, to measure the gap change in a non-contact manner and detect the horizontal displacement of the frame in real time.

10. The method for adjusting a flexible horizontal moving mirror for precision instruments according to claim 7, characterized in that, The external control system calculates the target displacement that the lens needs to be adjusted based on the aberration detection results, and uses a high-precision control algorithm to adjust the motor drive signal in real time to form a closed-loop control circuit until the displacement error between the actual displacement and the target displacement converges to the submicron level.

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