Laser output coupling device

Abstract

The present invention relates to the field of laser technology, and in particular to a laser output coupling device. The laser output coupling device comprises an output coupling mirror assembly, an adjustment assembly and a mounting plate; the bottom plate of the adjustment assembly is fixedly mounted on one side of the mounting plate, and the output coupling mirror assembly is fixedly mounted on the other side of the mounting plate; the adjustment assembly also comprises a first adjustment rod assembly and a first adjustment ball, a second adjustment rod assembly and a second adjustment ball; the bottom plate is provided with a first optical path channel, a first guide rail, a second guide rail and a groove; one side of the output coupling mirror assembly is provided with an inclined adjustment pin, a concave adjustment pin and a positioning block; the other side of the output coupling mirror assembly is pressed on the laser output coupling device by a fixing device with an elastic component, and the positioning block of the coupling mirror assembly is rotatably pressed in the groove on the bottom plate; the laser output coupling device provided by the present invention alleviates the technical problems of high difficulty in adjusting the output coupling device and danger existing in the prior art.

Description

Technical Field

[0001] The present application relates to the field of laser technology, and in particular to a laser output coupling device. Background Art

[0002] In the field of high-end lithography, high-repetition-rate excimer laser is the absolutely dominant light source used in the field of semiconductor lithography due to its high repetition rate, narrow linewidth and high energy.

[0003] In high-repetition-rate excimer laser systems, optical output encounters many problems. The first problem is that the laser emitted from the discharge cavity cannot meet the requirements of narrow linewidth and high energy.

[0004] In this regard, it is generally adopted to add an output coupling mirror with a certain reflectivity and transmittance to perform a return oscillation on the output laser, so as to increase its energy and output it after narrowing the line width. In the tuning process of the output coupling device, it is often necessary to spend a long time debugging in the resonant cavity state to obtain a higher energy output light. Moreover, the traditional structure in which the output light and the adjustment position are in the same direction not only increases the difficulty of tuning but also increases the risk of personnel during the adjustment process. The connection method at both ends of the traditional output coupling device is a cantilever flange connection, which is not stable enough after installation. After the complete optical path is connected, the tuning result will deviate again. In addition, for high-repetition-rate excimer lasers, the output light position needs to be turned on to determine the specific position, which causes inconvenience to the docking of the laser system. Summary of the invention

[0005] The object of the present invention is to provide a laser output coupling device to solve the problem that the existing output coupling device is difficult to adjust and there is danger to personnel during the adjustment process.

[0006] To achieve the above object, the present invention provides a laser output coupling device, which includes an output coupling mirror assembly, an adjustment assembly and a mounting plate;

[0007] The mounting plate is provided with a first optical path channel, the bottom plate of the adjustment assembly is fixedly mounted on one side of the first optical path channel, and the output coupling mirror assembly is fixedly mounted on the other side of the first optical path channel;

[0008] The adjustment assembly further includes a first adjustment rod assembly and a first adjustment ball, a second adjustment rod assembly and a second adjustment ball;

[0009] The bottom plate is provided with a second optical path channel, a first guide rail, a second guide rail and a groove;

[0010] A bevel-shaped adjustment pin, a concave-shaped adjustment pin and a positioning block are provided on one side of the output coupling mirror assembly;

[0011] The other side of the output coupling mirror assembly is pressed onto the laser output coupling device through a fixing device with an elastic component, and the positioning block of the coupling mirror assembly is rotatably pressed into a groove on the bottom plate;

[0012] The first adjusting ball is located between the first guide rail and the inclined-surface adjusting pin, one end of the first adjusting rod assembly contacts the first adjusting ball, and the first adjusting ball can slide along the first guide rail under the push of the first adjusting rod assembly;

[0013] The second adjusting ball is located between the second guide rail and the concave adjusting pin, one end of the second adjusting rod assembly contacts the second adjusting ball, and the second adjusting ball can slide along the second guide rail under the push of the second adjusting rod assembly;

[0014] The mounting plate is provided with a mounting hole which penetrates the first optical path channel, and the first adjusting rod assembly and the second adjusting rod assembly are both installed in the mounting hole.

[0015] The first adjusting rod assembly and the second adjusting rod assembly are both installed in the installation hole.

[0016] Preferably, the inclined surface adjusting pin, the concave surface adjusting pin and the positioning block are distributed in a triangle.

[0017] Preferably, the groove is a spherical groove, a conical groove or a truncated conical groove.

[0018] Preferably, the guide rail may be a V-groove guide rail, a trapezoidal groove guide rail or a spherical groove guide rail.

[0019] Preferably, the inclined surface of the inclined surface-shaped adjusting pin is a wedge surface or an inclined concave surface.

[0020] Preferably, the concave surface of the concave adjustment pin is V-shaped or concave spherical.

[0021] Preferably, the concave adjustment pin is an inclined V-shaped adjustment pin or an inclined concave spherical adjustment pin.

[0022] Preferably, the positioning block is a spherical positioning block or a truncated cone positioning block.

[0023] Preferably, the laser output coupling device further comprises a slit, and the slit is located between the output coupling mirror assembly and the bottom plate of the adjustment assembly.

[0024] Preferably, there are two mounting holes, and the two mounting holes are used to mount the first adjusting rod and the second adjusting rod respectively.

[0025] Preferably, the first adjusting rod assembly and the second adjusting rod assembly have different lengths.

[0026] Beneficial effects of the technical solution of the present invention: In the laser output coupling device provided by the present invention, the first adjusting ball can slide along the first guide rail under the push of the first adjusting rod assembly, and the second adjusting ball can slide along the second guide rail under the push of the second adjusting rod assembly, and the other ends of the first adjusting rod assembly and the second adjusting rod assembly extend to the outside of the mounting plate, so that the position of the output coupling mirror assembly arranged in the optical path channel can be changed through the adjustment mechanism on the outside of the mounting plate, thereby achieving the purpose of adjustment, thereby alleviating the technical problem of high difficulty and danger in adjusting the output coupling device in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : A schematic diagram of the appearance structure of a laser output coupling device provided in an embodiment of the present invention;

[0028] Figure 2 : A main isometric view of a laser output coupling device provided by an embodiment of the present invention;

[0029] Figure 3 : A schematic diagram of the connection between the adjustment component and the output coupling mirror component provided in an embodiment of the present invention;

[0030] Figure 4 : A schematic diagram of the structure of an output coupling mirror assembly provided in an embodiment of the present invention;

[0031] Figure 5 : A schematic structural diagram of a first adjusting rod assembly provided in an embodiment of the present invention;

[0032] Figure 6 : A schematic diagram of the installation of the slit structure provided in an embodiment of the present invention;

[0033] Figure 7 : A schematic structural diagram of a connecting socket assembly provided in an embodiment of the present invention;

[0034] Figure 8 : A schematic diagram of the structure of the output light directing mechanism provided by an embodiment of the present invention;

[0035] Fig. 9 : A schematic diagram of the structure of an optical path transposition mirror assembly provided in an embodiment of the present invention;

[0036] Fig.10 : A diagram showing a disconnected state of a laser output coupling device provided by an embodiment of the present invention;

[0037] Fig.11 : A pointing state diagram of a laser output coupling device provided by an embodiment of the present invention;

[0038] Fig.12 : A connection state diagram of a laser output coupling device provided by an embodiment of the present invention;

[0039] Fig.13 : Exploded view of the overall installation of the laser output coupling device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not constitute a limitation to the present application.

[0041] The present invention designs a Figure 1 The laser output coupling device shown in the figure. The mounting plate 1 is a carrier that carries all the mechanisms of the entire output coupling device; the window flange 2 is a sealing flange used to connect the optical path of the left end module, which is the input end of the optical path; the output flange 3 is a sealing flange used to connect the optical path of the right end module, which is the output end of the optical path.

[0042] The output coupling mirror assembly 4, the adjustment assembly 5, the output light pointing mechanism 6, the air inlet nozzle 7 and the connecting seat assembly 8 are installed on the mounting plate 1. Figure 2 shown.

[0043] The mounting plate 1 is provided with an output coupling device fixing interface 101, which adopts a three-point positioning method, and can effectively reduce the assembly deviation with the left end module. The whole is made of hard aluminum alloy, and can also be made of other materials with high rigidity and easy heat dissipation. An air inlet nozzle 7 is installed on the top of the mounting plate 1. The air inlet direction of the air inlet nozzle 7 can be perpendicular to both sides of the output coupling mirror optical path, and cannot directly cut the center of the optical path. The mounting plate 1 is provided with a first optical path channel, and a mounting hole that penetrates the first optical path channel is provided on the side.

[0044] The output coupling mirror assembly 4 is pressed on the mounting plate 1 by three spring-loaded shoulder set screws. Of course, the output coupling mirror assembly 4 can also be fixed on the mounting plate 1 by other devices with elastic structures. The structure of the output coupling mirror assembly 4 is as follows: Figure 3 and Figure 4As shown, the output coupling lens 402 is placed in the annular groove of the frame bottom plate 401, the upper surface of the output coupling lens 402 is pressed by the annular elastic element 403 with a flexible force, and the frame top plate 404 is installed and fixed, and the frame bottom plate 402 is respectively installed with a triangular distribution of concave adjustment pins 406, a bevel adjustment pin 407, a positioning block 405, a bevel adjustment pin 407, a positioning block 405, a bevel adjustment pin, and the concave adjustment pin and the positioning block are distributed in a triangular shape, and the installation position needs to adopt a positioning structure to ensure the angular accuracy of its installation. The positioning block 405 in this example is installed by interference fit, and the positioning groove structure is used to limit the angular direction freedom of the concave adjustment pin 406 and the bevel adjustment pin 407. The concave surface of the concave adjustment pin 406 limits the motion trajectory of the output coupling mirror assembly 4 when pitching, which can effectively prevent the output coupling mirror assembly 4 from shaking in other directions when performing two-dimensional adjustment.

[0045] The inclined surface of the inclined surface adjustment pin 407 is a wedge surface or an inclined concave surface. The concave surface of the concave surface adjustment pin 406 is V-shaped, trapezoidal, concave spherical or rectangular. The concave surface adjustment pin 406 itself can also be inclined, and the concave surface adjustment pin can be an inclined surface V-shaped adjustment pin, an inclined surface trapezoidal, an inclined surface concave spherical or an inclined surface rectangular adjustment pin. The positioning block 405 is a spherical positioning block or a truncated cone positioning block.

[0046] Adjustment component 5 as Figure 3 As shown, it includes a base plate 501, a first adjustment rod assembly 502, a second adjustment rod assembly 503, a first adjustment ball 504 and a second adjustment ball 505. The base plate 501 is made of stainless steel or other materials with high hardness, and has a second optical path channel, a first guide rail and a second guide rail. The first guide rail and the second guide rail can be V-shaped grooves, trapezoidal grooves or spherical grooves, etc., and the two can be the same or different. The guide rail can be a V-shaped groove, a trapezoidal groove or a spherical groove; the first adjustment ball 504 is located between the first guide rail and the beveled adjustment pin 407 of the output coupling mirror assembly 4, one end of the first adjustment rod assembly 502 is in contact with the first adjustment ball 504, and the first adjustment ball 504 of the output coupling mirror assembly 4 can slide along the first guide rail under the push of the first adjustment rod assembly 502; the second adjustment ball 505 is located between the second guide rail and the concave adjustment pin 406, one end of the second adjustment rod assembly 503 is in contact with the second adjustment ball 505, and the second adjustment ball 505 can slide along the second guide rail under the push of the second adjustment rod assembly 503.

[0047] Since the inclined adjustment pin 407, the positioning block 405, the inclined adjustment pin, the concave adjustment pin and the positioning block are distributed in a triangular shape, and the positioning block 405 is located in a direction biased toward one of the adjustment rods, the first adjustment rod assembly 502 and the second adjustment rod assembly 503 are two adjustment assemblies with the same structure and different lengths, which facilitates the tuning operation. The first adjustment rod assembly 502 has a structure as shown in FIG. Figure 5As shown. The left end of the adjustment rod 502.1 is a double-layer thread structure, the inner thread controls the extension and retraction of the adjustment top column 502.2, and the outer thread is used to install the plug 502.3 to seal the internal space. Of course, the structure of the adjustment rod assembly can also be other length-adjustable structures and sealed structures, as long as they can achieve the functions of adjusting the length and sealing, and the specific structure is not limited.

[0048] The method of using the adjustment component 5 is as follows: open the plug 502.3 of the first adjustment rod component 502, rotate and adjust the top column 502.2 to extend or retract it, adjust the top column 502.2 to push the first adjustment ball 504, and the first adjustment ball 504 moves forward along the first guide rail in the bottom plate 501, and lifts the spring on the shoulder set screw connected to the output coupling mirror component 4. The output coupling mirror component 4 uses the positioning block 5 as a support point to complete one-dimensional adjustment; when adjusting another dimension, the second adjustment rod component 503 is operated in the same way, and the output coupling mirror component 4 completes the tuning of another dimension with the positioning block 5 as a support point. By adjusting the first adjustment rod component 502 and / or the second adjustment rod 503, the adjustment of different dimensions and / or angles of the output coupling mirror component 4 is completed.

[0049] In another embodiment of the present invention, the first adjustment rod assembly 502 and the second adjustment rod assembly 503 can be two adjustment assemblies with the same structure and different lengths. Of course, the lengths can also be different, or the structures can be different. In addition, the two adjustment rods can be set on the same side, parallel to each other, or non-parallel at a certain angle, and the positions of the two guide rails on the bottom plate 501 and the positions of the two adjustment pins on the coupling mirror assembly 4 can be adjusted accordingly.

[0050] In another embodiment of the present invention, the two adjustment rods can also be set on different sides, and the structure and length can be the same or different, and they can be parallel or at a certain angle. The positions of the two guide rails on the base plate 501 and the positions of the two adjustment pins on the coupling mirror assembly 4 can be adjusted accordingly.

[0051] All of the above can achieve adjustment of different dimensions and / or angles of the output coupling mirror assembly 4 .

[0052] In order to facilitate calibration of the working angle of the output coupling mirror assembly 4, a slit structure 9 is added between the output coupling mirror assembly 4 and the incident light, such as Figure 6 As shown, it has the function of limiting the shape of the laser spot and filtering out stray light. The slit structure 9 can be circular, square or any other shape. The mounting plate 1 requires a positioning structure so that the slit structure 9 can be accurately installed and positioned. It can be a positioning groove with high precision, or it can be installed with a positioning pin, etc. When the slit structure 9 is used in conjunction with the slits of other modules on the left end of the output coupling device, there is no need for a resonant cavity state. The ideal position of the output coupling mirror can be achieved by tuning the output coupling device to align the laser with the center of the two slits.

[0053] The output light pointing mechanism 6 includes an alignment adjustment frame 601, a pointing light source 602, and an optical path transfer mirror assembly 603. The purpose of the optical path transfer mirror assembly 603 is to reflect the outgoing light of the pointing light source 602 to the same direction as the laser output light, and then fine-tune the pointing light source position by the alignment adjustment frame 601, so that the pointing light and the laser output light are aligned and positioned. After the pointing light source determines the position, the adjustment assembly 5 can be locked and fixed. After being fixed, the laser output position can be determined by the pointing light source optical path. The pointing light source 602 can select any low-power visible light generator, such as a laser diode, a helium-neon laser, etc.

[0054] The optical path transfer mirror assembly 603 is composed of a transfer base plate 603.1, an optical path transfer mirror 603.2, and a rotating fixing member 603.3. Fig. 9 As shown. The transposition base plate 603.1 has a light hole for pointing the optical path, and a positioning pin and a magnetic element are installed on the lower bottom surface. The optical path transposition mirror 603.2 is rotated by the rotating fixing member 603.3, and after the positioning pin docking and the adsorption of the magnetic element, the use and separation requirements of the pointing laser can be quickly completed. The optical path transposition mirror 603.2 can use a 45° right-angle prism, and the transposition is completed by the reflection of the 45° prism hypotenuse coating or the right-angle surface incidence through internal reflection. It can also use a plane reflector to swing to 45° for optical path transposition. Its fixing method can be UV adhesive bonding or mechanical support.

[0055] The connection base assembly 8 is composed of a connection base 801, a magnetic element 802, a first contact switch 803, and a second contact switch 804. The connection base 801 is installed on the outside of the output coupling mirror assembly 4, which can protect the output coupling mirror assembly 4 and seal the optical path. The outer surface of the connection base 801 has positioning pin holes and is equipped with magnetic elements 802. The number and position of the magnetic elements 802 are designed in association with the corresponding parts on the transposition base plate 603.1, which can help the optical path transposition mirror 603.2 to complete rapid positioning. The first contact switch 803 and the second contact switch 804 are installed side by side at the left end of the connection base.

[0056] The location detection function is implemented as follows Figure 10-12 When the optical path transfer mirror 603.2 is in the separation position, and the output flange 3 is normally connected to the connection seat assembly 8, at this time, the first contact switch 803 and the second contact switch 804 are not triggered, and the system can determine that the current state is disconnected. Fig.10 When the optical path transfer mirror 603.2 reaches the pointing position, the first contact switch 803 is not triggered, and the second contact switch 804 is triggered. The system can determine that the current state is pointing. Fig.11When the optical path transfer mirror 603.2 leaves the pointing position and the output flange 3 is installed, the first contact switch 803 and the second contact switch 804 are both triggered, and the system can determine that the laser output coupling device is currently connected in a good state. Fig.12 .

[0057] like Fig.13 As shown, the laser output coupling device of the present invention is composed of a mounting plate 1, a window flange 2, an output flange 3, an output coupling mirror assembly 4, an adjustment assembly 5 (including a base plate 501, adjustment rod assemblies 502, 503), an output light pointing mechanism 6 (including an alignment adjustment frame 601, a pointing light source 602, and an optical path transfer mirror assembly 603), an air inlet nozzle 7, a connecting seat assembly 8 and a slit structure 9.

[0058] The present embodiment provides a laser output coupling device having the following structural functions: the output coupling mirror placed laterally can be adjusted in two dimensions in the forward direction (normal operating direction); an air inlet interface can be provided to effectively dissipate the heat of the output coupling mirror and inject inert gas to ensure the stability of the optical path; an output light pointing mechanism is provided to facilitate moving in and out of the laser optical path; and an in-position detection function can be provided to monitor the connection status of the output flange and the optical path transfer mirror in real time to determine the connection status of the optical path.

[0059] Compared with the prior art, the above laser output coupling device can achieve the following beneficial effects:

[0060] (1) Effectively reduce the positioning deviation between the output coupling device interface and the left end module interface;

[0061] (2) The output coupling device can be reliably fixed in the system, reducing the overall deviation of the output coupling mirror caused by external forces;

[0062] (3) It can meet the needs of convenient tuning and calibration of the output coupling device and seal the optical path after tuning;

[0063] (4) The use of an integrated rotating rod effectively solves the problem of poor rotation caused by friction during tuning;

[0064] (5) The tuning method of using a steel ball to move in a guide rail to push the objective lens holder effectively solves the problem of idle travel and unstable offset in the adjustment of the output coupling device;

[0065] (6) The laser output position can be located by turning on the pointing light source without turning on the machine;

[0066] (7) Realize real-time monitoring of the connection status of the output coupling device to improve the reliability and maintainability of the equipment.

[0067] The first adjusting rod assembly and the second adjusting rod assembly of the tuning mechanism of this embodiment are respectively installed in two mounting holes of the mounting plate. In fact, they can also be installed in one mounting hole, or installed on the outside of the mounting plate, etc., and are not limited to the installation scope of this embodiment.

[0068] The first optical path channel of the mounting plate and the second optical path channel of the adjusting component bottom plate may be roughly concentric or unequal, as long as the passage of the laser can be guaranteed.

[0069] The specific implementation methods of the present application described above do not constitute a limitation on the protection scope of the present application. Any other corresponding changes and modifications made according to the technical concept of the present application should be included in the protection scope of the claims of the present application.

Claims

1. A laser output coupling device, characterized in that: The laser output coupling device comprises an output coupling mirror assembly, an adjustment assembly and a mounting plate; The mounting plate is provided with a first optical path channel; The bottom plate of the adjustment component is fixedly installed on one side of the first optical path channel, and the output coupling mirror component is fixedly installed on the other side of the first optical path channel; The adjustment assembly further includes a first adjustment rod assembly and a first adjustment ball, a second adjustment rod assembly and a second adjustment ball; The bottom plate is provided with a second optical path channel, a first guide rail, a second guide rail and a groove; A bevel-shaped adjustment pin, a concave-shaped adjustment pin and a positioning block are provided on one side of the output coupling mirror assembly; The other side of the output coupling mirror assembly is pressed onto the laser output coupling device through a fixing device with an elastic component, and the positioning block of the coupling mirror assembly is rotatably pressed into a groove on the bottom plate; The first adjusting ball is located between the first guide rail and the inclined-surface adjusting pin, one end of the first adjusting rod assembly contacts the first adjusting ball, and the first adjusting ball can slide along the first guide rail under the push of the first adjusting rod assembly; The second adjustment ball is located between the second guide rail and the concave adjustment pin, one end of the second adjustment rod assembly contacts the second adjustment ball, and the second adjustment ball can slide along the second guide rail under the push of the second adjustment rod assembly; the adjustment assembly is mounted on the mounting plate; The inclined surface adjusting pin, the concave surface adjusting pin and the positioning block are distributed in a triangle.

2. The laser output coupling device according to claim 1, characterized in that: The groove is a spherical groove, a conical groove or a truncated conical groove.

3. The laser output coupling device according to claim 1, characterized in that: The inclined surface of the inclined surface-shaped adjusting pin is a wedge surface or an inclined concave surface.

4. The laser output coupling device according to claim 1, characterized in that: The concave surface of the concave adjustment pin is V-shaped or concave spherical.

5. The laser output coupling device according to claim 4, characterized in that: The concave adjustment pin is an inclined V-shaped adjustment pin or an inclined concave spherical adjustment pin.

6. The laser output coupling device according to claim 1, characterized in that: The positioning block is a spherical positioning block or a truncated cone positioning block.

7. The laser output coupling device according to claim 1, characterized in that: The laser output coupling device further comprises a slit, wherein the slit is located between the output coupling mirror assembly and a bottom plate of the adjustment assembly.

8. The laser output coupling device according to claim 1, characterized in that: A mounting hole penetrating the first optical path is provided on the side of the mounting plate, and the first adjusting rod assembly and the second adjusting rod assembly are both installed in the mounting hole.

9. The laser output coupling device according to claim 8, characterized in that: There are two mounting holes, and the two mounting holes are used to mount the first adjusting rod assembly and the second adjusting rod assembly respectively.

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