Method for installing a processing apparatus and a beam transmission system for the processing apparatus

Abstract

In a processing apparatus equipped with a vibration isolation device, the optical axis in the optical transmission path of the beam transmission system is appropriately adjusted. [Solution] The laser processing apparatus 100 includes a beam transmission system 12 that transmits a laser beam between a light source 10 and an illumination optical unit 30 provided on the apparatus body 20. The beam transmission system 12 includes a second adjustment mirror 16 for adjusting the optical axis, and the position of the second adjustment mirror 16 along the vertical direction is on or near the upper end surface 90U of the vibration isolation device 90 that supports the support 80 of the apparatus body 20.

Description

Technical Field

[0001] The present invention relates to a processing apparatus for processing a substrate by a laser beam or the like, and more particularly to a processing apparatus provided with a vibration damping device for reducing vibration.

Background Art

[0002] With the miniaturization and high-density mounting of electronic devices and the like, high-precision pattern formation is required for printed wiring boards and the like. For example, in a laminated substrate, it is necessary to form fine vias and grooves on the order of μm.

[0003] As a method for performing microfabrication, ablation processing is performed. In this process, a laser beam with a high energy density is scanned over a mask and projected onto a workpiece such as a substrate. By instantaneously evaporating and removing the material surface in accordance with the mask pattern, vias and grooves for wiring can be formed on the substrate. The laser beam oscillated from the laser light source is guided to the illumination optical system provided in the processing apparatus main body through a laser transmission system (Laser Delivery System).

[0004] In the optical transmission path from the laser light source to the illumination optical system, if an optical axis deviation occurs, it will affect the processing accuracy. Therefore, the laser transmission system has a beam correction function, and by adjusting the angle of the mirror, the laser beam is made to enter the illumination optical system at an appropriate incident position and incident angle (see, for example, Patent Document 1).

[0005] During ablation processing, if vibration is transmitted from the outside to the processing apparatus main body, the vibration of the processing apparatus main body may cause a deviation in the projection position of the mask pattern, which may affect the processing accuracy. Therefore, a vibration damping device is provided for the processing apparatus main body (see Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2020-192550 [Patent Document 2] Japanese Patent Publication No. 2006-150419 [Overview of the project] [Problems that the invention aims to solve]

[0007] Even when the processing equipment is equipped with a vibration isolation system, vibrations inevitably propagate to the processing equipment itself, affecting optical components such as beam position correction mirrors in the beam transmission system. As a result, the range of position adjustment for optical components such as mirrors increases, and the tracking performance of optical axis adjustment in response to vibrations deteriorates. This affects processing accuracy.

[0008] Therefore, in processing equipment equipped with vibration isolation devices, it is necessary to appropriately adjust the optical axis in the optical transmission path of the beam transmission system. [Means for solving the problem]

[0009] A processing apparatus according to one aspect of the present invention comprises a main body of the apparatus equipped with a support that supports an illumination optical unit and a stage on which a workpiece is mounted, a beam transmission system that transmits a beam emitted from a light source installed independently of the main body of the apparatus toward the illumination optical unit, and a vibration isolation device that supports the support.

[0010] For example, the light source can be configured as a laser processing device that emits a laser beam. The beam correction optical component can be configured as a mirror that reflects the beam emitted from the light source and whose position can be changed. The main body of the device comprises a mask stage located below the illumination optical unit and a projection optical system located below the mask stage, with a support body supporting the mask stage and the projection optical system, so that the illumination optical unit, mask stage, projection optical system and stage can be integrated by the support body.

[0011] In the present invention, the beam transmission system has a main body-side beam transmission section supported by a support and equipped with a beam correction optical member that can adjust the optical axis of the beam, and the position of the beam correction optical member along the vertical direction is at or near the fulcrum of the vibration isolation structure in the vibration isolation device.

[0012] Here, "fulcrum of the vibration isolation structure" refers to the support point at which the vibration isolation device stabilizes the structure. For example, in the case of a vibration isolation table, the fulcrum can be considered to be on the upper surface. Furthermore, "near the fulcrum of the vibration isolation structure" can be defined as being near the fulcrum even if it does not strictly coincide with the fulcrum, as long as it is closer to the fulcrum than the support surface supporting the stage substrate, the projection optical system, the installation surface of the vibration isolation device, or the support surface supporting the stage. Alternatively, if the distance from the fulcrum is sufficiently small compared to the overall height of the device (for example, within ±150 mm if the device height is 3 m), it can be considered to be near the fulcrum.

[0013] The processing apparatus is installed on the floor and includes a base that supports the vibration isolation device, which can be positioned between the bottom of the support and the base. For example, the vertical position of the beam correction optical member can be configured to be lower than the workpiece mounting surface of the stage and above the pivot point of the vibration isolation structure.

[0014] The support structure can be configured to support the stage and include a stage support section located in the vertical direction, lower than the pivot point of the vibration isolation structure in the vibration isolation device.

[0015] Another aspect of the present invention relates to a method for installing a beam transmission system for a processing apparatus, which comprises an illumination optical unit, a support body that supports a stage on which a workpiece is mounted, and a base installed on the floor. The method involves installing a vibration isolation device between the bottom of the support body and the base so as to support the support body, and installing a light source that emits a beam independently of the apparatus body, and installing a beam that emits a beam from the apparatus light source toward the illumination optical unit. In this method, the beam transmission unit is installed in the main body side, which is equipped with a beam correction optical member that can adjust the optical axis of the beam, and is attached to the support body such that the position of the beam correction optical member along the vertical direction is the pivot point or near the pivot point of the vibration isolation structure of the vibration isolation device.

[0016] Another embodiment of the present invention is a processing apparatus comprising a main body having a support that supports an illumination optical unit and a stage on which a workpiece is mounted, a vibration isolation device that supports the support, and a base installed on the floor that supports the vibration isolation device, wherein the support surface of the support that supports the stage is located lower in the vertical direction than the fulcrum of the vibration isolation structure in the vibration isolation device. [Effects of the Invention]

[0017] According to the present invention, in a processing apparatus equipped with a vibration isolation device, the optical axis in the optical transmission path of the beam transmission system can be appropriately adjusted. [Brief explanation of the drawing]

[0018] [Figure 1] This is a schematic diagram of the laser processing apparatus according to this embodiment. [Figure 2] This is a schematic diagram of the beam transmission system. [Modes for carrying out the invention]

[0019] Figure 1 is a schematic diagram of the laser processing apparatus according to this embodiment.

[0020] The laser processing apparatus 100 is a processing apparatus capable of forming a pattern on a substrate (workpiece) W by ablation processing, and includes a light source device 10 and an apparatus main body 20. The light source device 10 is installed on the floor surface G independently of the apparatus main body 20.

[0021] The light source device 10 is a laser that oscillates laser light with a high energy density. Here, it is configured as an excimer laser that pulse-irradiates KrF excimer laser light with a wavelength of 248 nm. The laser light emitted from the light source device 10 is sent to the apparatus main body 20 via a beam transmission system 12.

[0022] The apparatus main body 20 is provided with an illumination optical unit 30, a scanning mechanism 40, a projection optical system 50, a mask stage 60, and a processing stage 70, and is supported by a support 80 of the apparatus main body 20. The support 80 having a frame structure with four legs that are equidistant from each other and extend vertically downward is installed on the base 25 of the apparatus main body 20. The mask M and the substrate W are respectively mounted on the mask stage 60 and the processing stage 70.

[0023] The illumination optical unit 30 has a line beam forming optical system (not shown) including a cylindrical lens or the like, and shapes the beam light flux of the laser light incident along the scanning direction into a line-shaped beam. The line-shaped light is guided to the mask M via a mirror not shown.

[0024] The illumination optical unit 30 is held by a pedestal not shown, and is installed such that the optical axis of the line beam forming optical system is parallel to the scanning direction. The scanning mechanism 40 that supports the pedestal is located at substantially the same height as the mask stage 60 and is arranged at adjacent positions along the scanning direction X.

[0025] The scanning mechanism 40 is capable of moving the illumination optical unit 30 back and forth along the scanning direction (X direction). As the illumination optical unit 30 moves, a line of light perpendicular to the scanning direction (X direction) moves relative to the mask M and the projection optical system 50, scanning the mask M and substrate W fixed to the mask stage 60 and processing stage 70, respectively.

[0026] The mask stage 60 holds the mask M and can position the mask M by moving and rotating in the X-Y direction. The projection optical system 50 is an optical system with focal points on the surface of the mask M and the surface of the substrate W, and projects light transmitted through the mask M onto the substrate W. Here, the projection optical system 50 is configured as a reduction projection optical system (e.g., magnification 1 / 4).

[0027] The processing stage 70 has a chuck function and fixes the substrate W by vacuum suction or the like. The processing stage 70 also positions the substrate W relative to the mask M by moving in the X-Y direction and rotating on the XY plane. Furthermore, it is capable of step-by-step movement along the scanning direction (X direction) so that ablation processing can be performed over the entire substrate W.

[0028] In this case, the substrate W is a resin substrate, with a copper wiring layer formed on a base material such as epoxy resin, and an insulating layer formed on top of that. By irradiating the substrate W with high-energy-density excimer laser light from the excimer laser light source device 10, ablation occurs on the substrate W, and a pattern corresponding to the mask pattern (hereinafter referred to as the processed pattern) is formed.

[0029] The processing patterns that can be formed include through-vias, non-through-vias, and trenches for wiring patterns. After the processing pattern is formed on the substrate W by ablation, a conductor such as copper is filled in.

[0030] The laser processing apparatus 100 includes a controller (not shown) that controls the operation of the ablation process. When an operator performs an operation to perform the ablation process, the controller drives and controls the light source device 10 and the scanning mechanism 40 to scan a line of light in the X direction. The controller also controls the movement of the mask stage 60 and the processing stage 70.

[0031] Figure 2 is a schematic diagram of the beam transmission system 12. The beam transmission system 12 comprises a light source-side beam transmission unit 12A and a main body-side beam transmission unit 12B, with a pipe 12C interposed between them. The beam transmission system 12 is equipped with a beam position correction mechanism (also called a beam steering mechanism) that adjusts the positioning of the laser beam L in real time.

[0032] Specifically, a first adjustment mirror 14 and a second adjustment mirror 16 are provided in the light source-side beam transmission section 12A and the main body-side beam transmission section 12B, respectively. The first adjustment mirror 14 and the second adjustment mirror 16 are movable in two axial directions.

[0033] The laser beam reflected by the first adjustment mirror 14 passes through the pipe 12C and enters the second adjustment mirror 16. The second adjustment mirror 16 reflects the laser beam propagated from the light source device 10 towards the illumination optical unit 30 (in this case, the vertical direction).

[0034] The light source device 10 emits a guide laser beam L1 along an optical path parallel to the processing laser beam L. After the guide laser beam L1 is reflected by the first adjustment mirror 14 and the second adjustment mirror 16, it is split into two optical paths by a beam splitter 18 located in the optical path, and one of them is incident on the sensor 19.

[0035] Sensor 19 is a sensor capable of detecting the (incident) position and angle of the guide laser beam, and in this case, it is composed of a PSD (Position Sensitive Detector). The controller of the main body of the device 20 corrects the optical axis of the beam transmission system 12 by feedback control. Specifically, it drives and controls two actuators (not shown) to adjust the positions of the first and second adjustment mirrors 14 and 16 based on the output signals from sensor 19. Note that the system may be configured to adjust the position of only the second adjustment mirror 16.

[0036] The vibration isolation device 90 is a device that reduces vibrations transmitted to the main body 20 of the device, and is installed between the support body 80 and the base 25 installed on the floor. Four vibration isolation devices 90 (only two are shown in Figure 1) are installed to support the support body 80, which has four legs. The vibration isolation device 90 is configured here as a passive vibration isolation device and is equipped with an air spring. However, the vibration isolation device 90 may also be configured as an active vibration isolation device.

[0037] The support body 80 includes a stage support section 21 that supports the processing stage 70 and a stage moving mechanism (not shown). The stage support section 21 has a concave cross-section along the scanning direction (X direction), and the support surface 21B on which the processing stage 70 and the stage moving mechanism are mounted is located below the contact surface 21T with the vibration isolation device 90 along the vertical direction (Z direction).

[0038] During laser processing, equipment placed near the device acts as a vibration source, and vibrations are transmitted to the laser processing device 100 through the floor surface G. The vibration isolation device 90 operates with its upper end surface 90U as a pivot point to prevent vibrations from being directly transmitted to the support 80. In Figure 1, the plane along the upper end surface 90U of the four vibration isolation devices 90 (hereinafter referred to as the pivot surface) is indicated by the symbol U.

[0039] The illumination optical unit 30, scanning mechanism 40, projection optical system 50, mask stage 60, processing stage 70, and main body-side beam transmission unit 12B are integrated through the support 80. Therefore, when the vibration isolation device 90 operates to reduce vibrations, the support 80 supported by the vibration isolation device 90 moves, and the position of the second adjustment mirror 16 changes accordingly.

[0040] Furthermore, when the illumination optical unit 30 moves due to the scanning mechanism 40, vibrations associated with the movement are transmitted to the main body beam transmission unit 12B, and the center of gravity of the device body 20 shifts. The movement of the mask stage 60 and the processing stage 70 also causes a shift in the center of gravity. If these shifts in the center of gravity are large, the position of the second adjustment mirror 16 will change.

[0041] As described above, the first and second adjustment mirrors 14 and 16 of the beam transmission system 12 are positioned by feedback control so that the optical axis of the laser beam L is properly incident on the illumination optical unit 30. However, when the amount of movement of the first and second adjustment mirrors 16 increases, the tracking accuracy of the first and second adjustment mirrors 14 and 16 decreases, making it difficult to properly adjust the optical axis position of the laser beam L.

[0042] In this embodiment, the main body-side beam transmission unit 12B is installed near the stage support unit 21 located at the bottom of the support body 80. The second adjustment mirror 16 of the beam transmission system 12 is located near the pivot point (upper end surface 90U) of the vibration isolation structure in the vibration isolation device 90. In other words, the position along the vertical direction of the optical axis of the laser beam L between the first adjustment mirror 14 and the second adjustment mirror 16 is located near the pivot surface U.

[0043] The position of the second adjustment mirror 16, that is, its position along the vertical direction of the optical axis of the laser beam L, is closer to the upper end surface 90U of the vibration isolation device 90 than to the support surface N of the substrate W, the projection optical system 50, the installation surface of the vibration isolation device 90, and the support surface 21B. The position of the second adjustment mirror 16 is the position of the member closest to this upper end surface 90U, and this can be defined as the range near the pivot point of the vibration isolation structure.

[0044] Since the second adjustment mirror 16 is positioned near the starting point of the positional fluctuation (oscillation) of the support 80, optical axis adjustment can be performed while suppressing the amount of movement of the first and second adjustment mirrors 14 and 16. Here, the optical axis of the laser beam L between the first adjustment mirror 14 and the second adjustment mirror 16 is above the pivot surface U and below the support surface N of the processing stage 70 on which the substrate W is mounted.

[0045] Because the vibration isolation device 90 is interposed between the base 25 and the support 80, and the device body 20 is divided into an upper and lower section, it is possible to position the second adjustment mirror 16 near the bottom of the support 80 while keeping the distance between the illumination optical unit 30, which is installed at the very top of the device body 20, and the main body-side beam transmission section 12B to a minimum.

[0046] Furthermore, by positioning the support surface 21B of the stage support section 21 below the pivot surface U and positioning the processing stage 70 closer to the floor, the center of gravity of the apparatus body 20 is lowered. This allows the apparatus body 20 to maintain a stable posture against external vibrations.

[0047] As described above, the laser processing apparatus 100 of this embodiment includes a beam transmission system 12 that transmits a laser beam between the light source 10 and the illumination optical unit 30 provided on the apparatus body 20. The beam transmission system 12 includes a second adjustment mirror 16 for adjusting the optical axis, and the position of the second adjustment mirror 16 along the vertical direction is on or near the upper end surface 90U of the vibration isolation device 90 that supports the support 80 of the apparatus body 20.

[0048] Furthermore, by focusing on the configuration in which the support surface 21B of the stage support section 21 is located below the pivot surface U, the effects of vibration can be suppressed by lowering the center of gravity of the device body 10. Therefore, it becomes possible to effectively adjust the optical axis regardless of the position of the second adjustment mirror 16.

[0049] The beam transmission system can be configured in ways other than those described above. It is also possible to use a device body without a base. Furthermore, it may be applied to processing equipment using beams other than laser beams. [Explanation of Symbols]

[0050] 10 Light source device 12 Beam transmission systems 14. First Adjustment Mirror 16. Second adjustment mirror (beam correction optical component) 20 Main unit of the device 30 Illumination Optical Units 70 Processing Stages (Stages) 80 Support 90 Vibration isolator 100 Laser Processing Equipment

Claims

1. The apparatus body includes a support structure that provides an illumination optical unit and a stage on which the workpiece is mounted, A beam transmission system that transmits a beam emitted from a light source installed independently of the main body of the aforementioned device toward the illumination optical unit, The system includes a vibration isolation device that supports the aforementioned support, The beam transmission system has a main body-side beam transmission section supported by the support and equipped with a beam correction optical member capable of adjusting the optical axis of the beam, A processing apparatus characterized in that the position of the beam correcting optical member along the vertical direction is at or near the pivot point of the vibration isolation structure in the vibration isolation device.

2. It is installed on the floor and has a base that supports the vibration isolation device, The processing apparatus according to claim 1, characterized in that the vibration isolation device is disposed between the bottom of the support and the base.

3. The processing apparatus according to claim 2, characterized in that the position of the beam correction optical member along the vertical direction is lower than the workpiece mounting surface of the stage and above the pivot point of the vibration isolation structure.

4. The processing apparatus according to claim 1, characterized in that the support body supports the stage and has a stage support portion located in the vertical direction at a position lower than the fulcrum of the vibration isolation structure in the vibration isolation device.

5. The processing apparatus according to any one of claims 1 to 4, characterized in that the beam correction optical member is composed of a mirror that reflects the beam emitted from the light source and whose position can be changed.

6. The apparatus body comprises a mask stage located below the illumination optical unit and a projection optical system located below the mask stage, The support supports the mask stage and the projection optical system. The processing apparatus according to any one of claims 1 to 4, characterized in that the illumination optical unit, the mask stage, the projection optical system, and the stage are integrated by the support.

7. The processing apparatus according to any one of claims 1 to 4, characterized in that the light source oscillates a laser beam.

8. The apparatus body comprises an illumination optical unit, a support body that supports a stage on which a workpiece is mounted, and a base installed on the floor. A vibration isolation device is installed between the bottom of the support body and the base so as to support the support body. The light source that emits the beam is installed independently of the main body of the device. A method for installing a beam transmission system that transmits a beam emitted from the aforementioned device light source toward the aforementioned illumination optical unit, A method for installing a beam transmission system on a processing apparatus, characterized in that the main body-side beam transmission section, which is provided with a beam correction optical member capable of adjusting the optical axis of the beam, is attached to the support such that the position of the beam correction optical member along the vertical direction is at or near the pivot point of the vibration isolation structure of the vibration isolation device.

9. The apparatus body includes a support structure that provides an illumination optical unit and a stage on which the workpiece is mounted, A vibration isolation device that supports the aforementioned support, It is installed on the floor and comprises a base that supports the vibration isolation device, A processing apparatus characterized in that the support surface of the support body that supports the stage is located at a lower position in the vertical direction than the fulcrum of the vibration isolation structure in the vibration isolation device.

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