Laser drilling system and method for selective removal of insulating layer

Abstract

This invention provides a laser drilling system and a method for selectively removing an insulating layer that simplify the process and enable efficient process execution. [Solution] The method includes a workpiece 10 including an insulating layer 15 disposed on its surface, a stage on which the workpiece is placed, an optical transmission system 400 disposed on the stage for transmitting secondary laser light L2 to the insulating layer, a laser beam generator connected to the optical transmission system and outputting primary laser light L1, a blowing-suction device 500 disposed between the workpiece and the optical transmission system, a monitoring-inspection device for inspecting the surface shape of the workpiece, and a control device that controls the laser light generated from the laser beam generator and / or the optical transmission system in accordance with the surface shape information, wherein the optical transmission system controls the laser light by a diffraction optical system 4010.

Description

Technical Field

[0001] Embodiments can simplify processes and proceed efficiently, and can form holes even when it is substantially difficult to form hole shapes intended by general lithography techniques, such as small-sized holes or holes with a large aspect ratio. The embodiments relate to a laser drilling system, a method for selectively removing an insulating layer, etc.

Background Art

[0002] In the manufacturing process for electronic components, the front-end (FE) process can implement a circuit on a semiconductor wafer, and the back-end (BE) process can assemble the wafer into a state where it can be used as an actual product. The packaging process may be included in the back-end process.

[0003] Four core technologies of the semiconductor industry that have enabled the remarkable development of recent electronic products are semiconductor, semiconductor packaging, semiconductor manufacturing, and software technology.

[0004] Semiconductor technology has developed in various fields such as sub-micron nanoscale line widths, over 10 million cells, high-speed operation, and heat dissipation. However, complete packaging technology is not supported. Therefore, the electrical performance of a semiconductor may be determined more by packaging technology and the electrical connections thereby than by the performance of the semiconductor technology itself.

[0005] One method introduced to improve electrical performance is vertical connection. Vias are an example of this vertical connection structure, and laser drilling can be applied to form them. When forming small vias using lithography methods such as exposure and development, technical difficulties can arise as the depth of the via hole increases. For example, it is difficult to ensure the external shape of the hole, such as the size of the hole opening and the aspect ratio, with sufficient reliability, so additional steps such as plasma etching may be required, which can lead to difficulties such as increased complexity of the steps and equipment, and decreased yield.

[0006] On the other hand, the aforementioned background technology is technical information that the inventor possessed for the purpose of deriving the present invention, or acquired during the process of deriving the present invention, and is not necessarily publicly known technology that was made public before the filing of the present invention.

[0007] Relevant prior art includes Korean Registered Patent No. 10-2477657 and Korean Published Patent No. 10-2016-0110780. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The purpose of this embodiment is to provide a laser drilling system and the like that simplifies the process and enables efficient process execution.

[0009] Another objective of the embodiment is to provide a laser drilling system that can create patterns with different shapes, sizes, and depths, such as lines, holes, and pads, in essentially a single laser drilling operation.

[0010] Another objective of the embodiment is to provide a laser drilling system that can form holes even in cases where it is difficult to form the intended hole shape using general exposure techniques, such as small holes or holes with a large aspect ratio. [Means for solving the problem]

[0011] This summary is provided to illustrate some of the simplified forms of concepts that are described in more detail in the detailed explanation below. This summary is not intended to distinguish the principal or core features claimed as rights, nor is it intended to be used to help determine the scope of the claimed rights.

[0012] To achieve the above objective, the laser drilling system according to the embodiment includes: a workpiece including an insulating layer; a stage on which the workpiece is placed; an optical transmission system placed on the stage for transmitting laser light to the insulating layer; a laser beam generator connected to the optical transmission system for outputting laser light; a blowing-suction device placed between the workpiece and the optical transmission system; a monitoring-inspection device for inspecting the surface shape of the workpiece; and a control device that controls the laser light generated from the laser beam generator and / or the optical transmission system in accordance with the surface shape information.

[0013] The object to be processed may be one in which the insulating layer is disposed on the metal layer.

[0014] The optical transmission system can control the laser light using a diffraction optical system.

[0015] The diffraction optical system can be fitted with a patterned quasi-binary phase mask.

[0016] The optical transmission system can filter the laser light into linear polarization, pattern it based on information provided by the control device using a diffraction optical system, and after manifesting partially different light intensities, convert the linear polarization back into circular polarization and transmit it to the workpiece.

[0017] The optical transmission system may include: a primary beam quality control system through which laser light generated from the laser beam generator passes; a diffraction optical system through which the light that has passed through the primary beam quality control system is modulated; and a circular polarization unit through which the light that has passed through the diffraction optical system is converted into circular polarization.

[0018] The circular polarizing unit may include: a first circular polarizer through which light modulated by the diffractive optical system passes; a polarizer through which light that has passed through the first circular polarizer passes; and a second circular polarizer through which light that has passed through the polarizer passes.

[0019] The diffraction optical system may include a spatial light modulator.

[0020] The spatial light modulator may be equipped with a liquid crystal that induces phase modulation and amplitude modulation of the laser light.

[0021] The diffractive optical system may include a liquid crystal substrate spatial light modulator, a micromirror array-based spatial light modulator, a deformable mirror, or a diffractive optical element.

[0022] A selective removal method for an insulating layer according to another embodiment includes: a placement step of placing the workpiece on a stage; and an etching step of irradiating the workpiece with laser light converted from primary laser light output from a laser beam generator to secondary laser light by passing it through an optical transmission system to which a diffraction optical system is applied.

[0023] The object to be processed includes an insulating layer, and the secondary laser beam removes a portion of the insulating layer. Specifically, the insulating layer is etched in a predetermined pattern and to a predetermined depth so that a pattern including via holes, pads, lines, or all of these can be formed on the insulating layer.

[0024] The etching step may include a primary processing process in which the primary laser light passes through a beam quality control device via a transmission optical system, and a secondary processing process in which the primary laser light is emitted as secondary laser light whose pattern and intensity are adjusted according to the shape to be processed through the diffractive optical system.

[0025] The etching step may further include a control process.

[0026] The control process may include a process of checking whether abnormal intensity and shape of zero order occur in the diffractive optical system, and a process of adjusting the abnormal intensity and shape to be located at a dummy or pad in the processing target.

Advantages of the Invention

[0027] The laser drilling system of the embodiment can simplify the process and proceed efficiently, and can substantially implement patterns with different shapes, sizes, and depths, such as lines, holes, and pads, by one-time laser drilling. Also, it can be formed even when it is difficult to form the intended hole shape by general exposure techniques, such as small holes or holes with a high aspect ratio.

Brief Description of the Drawings

[0028] [Figure 1] It is a conceptual diagram for explaining the laser drilling system according to the embodiment. [Figure 2] It is a conceptual diagram for explaining the progress of the etching step in the optical transmission system according to the embodiment in cross section. [Figure 3] It is a conceptual diagram for explaining the optical transmission system according to the embodiment.

Best Mode for Carrying Out the Invention

[0029] The following detailed descriptions are provided to help you understand the methods, apparatus and / or systems described herein comprehensively. However, after understanding the disclosures of this application, various changes, modifications and equivalents of the methods, apparatus and / or systems described herein will become apparent. For example, the work sequences described herein are merely illustrative and are not limited to the work explicitly stated herein, but are modifiable as will become apparent after understanding the disclosures of this application, except for work that is not necessarily performed in a specific order. Furthermore, after understanding the disclosures of this application, descriptions of known features may be omitted for clarity and brevity, and the omission of such features and descriptions does not imply that they are considered common knowledge.

[0030] The features described herein can be embodied in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein are provided merely to illustrate some of the many possible ways of embodying the methods, apparatus and / or systems described herein, which will become apparent after understanding the disclosure of this application.

[0031] Terms such as “first,” “second,” and “third” are available herein to describe various components, regions, layers, or sections, but such components, regions, layers, or sections are not limited by such terms. Rather, these terms are used to distinguish one member, part, region, layer, or section from other members, parts, regions, layers, or sections. Accordingly, a first member, part, region, layer, or section referred to in the examples described herein may be called a second member, part, region, layer, or section without departing from the teachings of the examples.

[0032] Throughout this specification, when an element such as a layer, region, or substrate is described as being "on top of," "connected to," or "joined" another element, it means that it is directly "on top of," "connected to," or "joined" the other element, or that one or more other elements may intervene between them. Conversely, when an element is described as being "directly on top of," "directly connected to," or "directly joined to," no other elements may intervene between them. Similarly, expressions such as "between" and "directly between" and "indirectly introduced" and "directly introduced" may be interpreted as described above.

[0033] The terms used herein are used solely for the purpose of illustrating specific examples and are not used to limit this disclosure. The singular forms “a,” “an,” and “the” as used herein may include plural forms unless the context clearly indicates otherwise. The terms “and / or” as used herein include one or more combinations of the listed items. The terms “include,” “comprise,” and “have” as used herein indicate the presence of an expressed feature, number, operation, element, component, and / or combination thereof, but do not exclude the presence or addition of one or more other features, numbers, operations, elements, components, and / or combinations thereof. In relation to examples (e.g., in relation to what an example or example includes or can embody), the use of the term “may” herein means that there is at least one example or example in which such features are included or embody, but not all examples are limited thereto.

[0034] Throughout this specification, “B being positioned on A” means that B is positioned in direct contact with A or on A with other layers or structures interposed between them, and is not limited to B being positioned in direct contact with A. Unless otherwise defined, all terms used in this document have the same meaning as that generally understood by an ordinary technician in the art relating to this document, given an understanding of this document, and this is consistent thereafter.

[0035] Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and this disclosure, and not as an ideal or overly formal meaning unless expressly defined herein.

[0036] Figure 1 is a conceptual diagram illustrating a laser drilling system according to an example, and Figure 2 is a conceptual diagram illustrating the progress of the etching step in the optical transmission system according to an example in cross-section. Figure 3 is a conceptual diagram illustrating the optical transmission system according to an example. The example will be described in more detail below with reference to the above drawings.

[0037] To achieve the above objective, the laser drilling system according to the embodiment includes a stage 100, an optical transmission system 400, a laser beam generator 300, a blowing-suction device 500, a monitoring-inspection device 600, and a control device 200 (see Figure 1).

[0038] The aforementioned configurations are interconnected to perform selective etching of the workpiece 10 within the laser drilling system.

[0039] The object to be processed 10 includes an insulating layer 15 placed on its surface.

[0040] The object to be processed 10 includes a metal layer 13 and an insulating layer 15 placed on the metal layer 13 (see Figure 2).

[0041] For example, the object to be processed 10 may be a packaging substrate applied to the packaging of a semiconductor device. When the packaging substrate is applied as the object to be processed 10, a glass core 11 may be applied. Specifically, the object to be processed 10 may include a glass core 11 having through vias, a metal layer 13 disposed on both sides of the glass core 11 and on the through vias, and an insulating layer 15 disposed on the metal layer 13.

[0042] The workpiece 10 has an insulating layer, and the metal layer may be positioned above and / or below the insulating layer. Selective removal of the insulating layer allows for the formation of a metal layer (electrically conductive layer) on the workpiece 10 in a subsequent step, which may become a wire pattern on the packaging substrate.

[0043] In conventional processes, forming a metal layer (electrically conductive layer) required a very complex multi-step process.

[0044] Conventionally, the following process is performed to form a pattern on a workpiece that includes holes, pads, and lines: 1) the substrate to be processed is cleaned, 2) a metal layer is formed by a method such as sputtering, 3) pretreatment is performed, 4) a lithography process is carried out, 5) plating is performed, 6) annealing and etching are performed, 7) the cleaning process is carried out again, 8) pretreatment is performed again, 9) insulating material is placed, 10) it is cured to produce an insulating layer, 11) via holes are formed, 12) desmear is performed, 13) cleaning is performed, 14) then a metal layer is formed, 15) pretreatment is performed, 16) a lithography process is carried out, 17) plating is performed, and 18) annealing and etching are performed. This process is repeated to form a single layer of pattern.

[0045] In this concrete example, the portion of the insulating layer that forms the pattern is removed, but instead of forming each line and each hole separately as described above, holes, pads, lines, etc. can be formed through the laser drilling process, thus simplifying and improving the efficiency of the process. When the portion of the insulating layer that forms the pattern is removed in this way, if a process such as plating is performed there, it becomes possible to efficiently form a metal layer in the shape of a pattern.

[0046] Stage 100 is the apparatus on which the workpiece 10 is placed.

[0047] On the stage 100, the workpiece 10 is positioned by an automated device (e.g., a robotic arm), and its position after positioning can be checked and corrected by the monitoring-inspection device 600 and the control device 200. At this time, alignment marks (not shown) are placed on the workpiece 10, and the monitoring-inspection device 600 detects its relative position to the stage 100, etc. When this information is transmitted to the control device 200, the control device 200 can check whether the position is appropriate and adjust the position of the workpiece 10, etc.

[0048] The laser beam generator 300 is connected to the optical transmission system 400 and outputs laser light L.

[0049] The laser light L may be one that has an absorption rate suitable for processing metallic materials such as copper and titanium. Alternatively, the laser light L may be one that has an absorption rate suitable for processing organic layers or organic-inorganic composite layers such as insulating layers (e.g., the cured layer of Ajinomoto build-up film), polyimide layers, and photoresist layers.

[0050] Specifically, the laser light L may be one having a UV wavelength. For example, the laser light L may have wavelengths of 400 nm or less, 350 nm or less, 340 nm or less, 330 nm or less, 320 nm or less, 310 nm or less, 300 nm or less, 290 nm or less, 280 nm or less, 270 nm or less, 260 nm or less, or 250 nm or less. The laser light L may also have wavelengths of 100 nm or more.

[0051] The laser light L may have a pulse energy of 10 mJ or more, 15 mJ or more, 20 mJ or more, 25 mJ or more, 30 mJ or more, 35 mJ or more, 40 mJ or more, 45 mJ or more, 50 mJ or more, 55 mJ or more, 60 mJ or more, 65 mJ or more, 70 mJ or more, or 75 mJ or more. The pulse energy may also be 200 mJ or less, 150 mJ or less, or 1 J or less. When such pulse energies are applied, insulating layers and the like can be removed more efficiently.

[0052] The laser light L may have a pulse repetition rate of 10 Hz or higher, 50 Hz or higher, 100 Hz or higher, 300 Hz or higher, 600 Hz or higher, 900 Hz or higher, 1,000 Hz or higher, 2,000 Hz or higher, 3,000 Hz or higher, 4,000 Hz or higher, or 5,000 Hz or higher. The pulse repetition rate may be 10 kHz or lower.

[0053] The aforementioned laser beam L can process shapes with high resolution while simultaneously applying a relatively high repetition rate and relatively high energy.

[0054] The laser light L, in particular, makes it possible to realize reliable vias having a diameter of 20 μm or less when the depth is 20 μm or less.

[0055] However, the laser light L is not limited to those having the characteristics described above.

[0056] The optical transmission system 400 is positioned on the stage 100 and transmits the laser light L to the insulating layer 15.

[0057] The laser light L is not transmitted directly to the workpiece 10, but rather the laser light is transmitted after passing through the optical transmission system 400 and being converted.

[0058] The laser light L output from the laser beam generator 300 is called the primary laser light L1, and the light emitted from the optical transmission system 400 to the insulating layer 15 is called the secondary laser light L2.

[0059] In the optical transmission system 400, the primary laser light L1 is converted into secondary laser light L2 by the diffraction optical system 4010.

[0060] The optical transmission system can filter the laser light into linear polarization, pattern it based on information provided by the control device via the diffraction optical system 4010, and after manifesting partially different light intensities, convert the linear polarization back into circular polarization and transmit it to the workpiece.

[0061] The diffraction optical system 4010 can be fitted with a patterned quasi-binary phase mask.

[0062] The diffraction optical system 4010 may include a spatial light modulator (SLM).

[0063] The diffraction optical system 4010 may include a liquid crystal-based spatial light modulator.

[0064] The diffraction optical system 4010 may include a digital micromirror device based spatial light modulator.

[0065] The diffraction optical system 4010 may include a deformable mirror.

[0066] The diffractive optical system 4010 may include a diffractive optical element (DOE).

[0067] The diffraction optical system 4010 can induce phase modulation and amplitude modulation of the laser light.

[0068] The optical transmission system 400 may include a primary beam quality control system 4005 through which the laser light generated from the laser beam generator passes; a diffraction optical system 4010 through which the light that has passed through the primary beam quality control system 4005 is modulated; and a circular polarization unit 4020 through which the light that has passed through the diffraction optical system 4010 is converted into circular polarization.

[0069] A lens (not shown) may be further positioned behind the circular polarizing unit 4020.

[0070] The primary beam quality control system 4005 may, for example, utilize a half-wave plate (HWP).

[0071] The diffraction optical system 4010 is as described above.

[0072] The circular polarization unit 4020 contains a circular polarizer (quarter wave plate, QWP). The circular polarizer converts linear light into circularly polarized light.

[0073] The circular polarizing unit 4020 may include a first circular polarizer (quarter wave plate, QWP) through which light modulated by the diffraction optical system 4010 passes; a polarizer through which light that has passed the first circular polarizer passes; and a second circular polarizer (quarter wave plate, QWP) through which light that has passed the polarizer passes.

[0074] Light that has passed through the circular polarization unit 4020 can further pass through a secondary beam quality control system (not shown). For example, the secondary beam quality control system may include lenses or the like, but is not limited to this.

[0075] The optical transmission system 400 does not apply a substantially patterned mask, and as an example, it enables the laser etching of patterns of different shapes and depths, such as holes, lines, and pads, by inducing changes in liquid crystals. Furthermore, it enables high-speed etching of the insulating layer with excellent resolution. Since the laser irradiation operation can be performed while changing the pattern by controlling the characteristics of the diffractive optical system located inside the optical transmission system, without applying a separate patterned mask, it is possible to achieve significantly improved process speed and efficiency.

[0076] The laser light L can, through the optical transmission system 400, form patterns on the insulating layer 15 including via holes with controlled depth and diameter; pads with controlled depth and diameter; lines with controlled depth and width; or all of these.

[0077] The pattern is formed by etching with the aforementioned laser light. This pattern is formed by selectively removing a portion of the insulating layer. If such particulate byproducts remain inside the etched pattern within the formed insulating layer, cleaning may become difficult in subsequent processes, and disconnections may occur in those processes.

[0078] During the etching process using the laser light L, particulate impurities or smear P, which are processing by-products, are formed. These need to be removed before any subsequent processes are carried out.

[0079] The blowing-suction device 500 removes particulate impurities or smear P generated when the insulating layer 15 is removed by the laser light L from the insulating layer 15 using air pressure.

[0080] The blowing-suction device 500 is positioned between the workpiece 10 and the optical transmission system 400. This arrangement makes it easier to remove particulate impurities or smear.

[0081] Blowing can, but is not limited to, gases such as CDA (Clean Dry Air) and N2.

[0082] These particulate by-products or smears are present in part of the etched pattern and can fall onto the insulating layer. A processing protection layer (not shown) can be selectively placed on the insulating layer, thereby making the particulate by-products or smears easier to remove. Specifically, the particulate by-products or smears can be guided to fall onto the processing protection layer rather than directly onto the surface of the insulating layer. This allows for easier removal of the particulate by-products or smears in subsequent processes, such as removing the processing protection layer, and then removing the processing protection layer during subsequent cleaning processes. The processing protection layer may, for example, be a polymer film (e.g., polyethylene terephthalate film, polyimide film).

[0083] The monitoring and inspection device 600 is a device for inspecting the surface shape information of the workpiece 10.

[0084] The control device 200 controls the laser light L generated from the laser beam generator 300 and / or the optical transmission system 400, reflecting the surface shape information.

[0085] The monitoring and inspection device 600 and the control device 200 acquire information from the workpiece, perform calculations based on this information, and help ensure appropriate laser irradiation and selective removal of the insulating layer.

[0086] For example, the workpiece 10 has alignment marks, and the control device 200 can control the position of the workpiece 10 and / or the position to which the laser light is irradiated through the alignment marks.

[0087] For example, the workpiece 10 has alignment marks, and the control device 200 can control the processing height by the laser beam L.

[0088] For example, the workpiece 10 has alignment marks, and the control device 200 can control the size of the focal point of the laser beam L.

[0089] The control device 200 can control the temperature and humidity within the laser drilling system.

[0090] The laser drilling system allows for the division of the insulating layer into regions and the sequential formation of etched patterns on the insulating layer. By controlling the radar beam, the shape, width, and depth of the patterns can be controlled, enabling laser drilling with high accuracy in a relatively short process time.

[0091] A selective removal method for an insulating layer according to another embodiment includes a placement step and an etching step, wherein the insulating layer to be processed is etched to form an incised pattern.

[0092] The placement step controls the position of the workpiece 10 and places it on the stage 100.

[0093] The arrangement step may include a process in which the stage 100 secures the workpiece 10 with clamps or vacuum to mitigate warping.

[0094] The object to be processed 10 includes an insulating layer 15. The object to be processed 10 includes a metal layer 13 and an insulating layer 15 disposed on the metal layer 13. The metal layer 13 may be an electrically conductive layer (i.e., a patterned metal layer) disposed beneath the insulating layer in the packaging substrate. Alternatively, the metal layer 13 may be a seed layer disposed beneath the insulating layer in the packaging substrate.

[0095] The insulating layer 15 may be an organic layer or an organic-inorganic composite layer. For example, the insulating layer can be provided by placing a sheet-like insulating material on the metal layer 13 together with a release film such as a PET film, performing vacuum lamination or the like, and then curing or semi-curing it.

[0096] The aforementioned release film, such as the PET film, may be used as the processing protective layer as described above, if necessary.

[0097] The etching step involves converting the primary laser beam L1 output from the laser beam generator 300 into a secondary laser beam L2, and then irradiating the workpiece 10 with it. Specifically, the primary laser beam output from the laser beam generator is converted into a secondary laser beam by passing it through an optical transmission system to which a diffraction optical system is applied, and this laser beam is irradiated onto the workpiece to etch it to a predetermined shape and depth.

[0098] The secondary laser light L2 forms a pattern on the insulating layer 15 that includes via holes, pads, lines, or all of these.

[0099] The etching step may include a primary processing step in which the primary laser light passes through a transmission optical system and a beam quality control device; and a secondary processing step in which the primary laser light passes through the diffraction optical system and is emitted as secondary laser light whose pattern and intensity are adjusted according to the shape to be processed.

[0100] Specifically, the beam emitted from the laser passes through a transmission optical system, then a beam quality control system to first determine the processing shape, and then a diffraction optical system to secondarily form a processing pattern, before reaching the processing position, making it possible to process holes and patterns simultaneously.

[0101] The etching step may further include a control process.

[0102] The control process may further include a process of checking whether an abnormal intensity and shape of the order of zero occurs in the diffraction optical system; and a process of adjusting the abnormal intensity and shape so that it is located on a dummy or pad in the workpiece.

[0103] The insulating layer removal method may further include a particle removal step simultaneously with or after the etching step.

[0104] The particle removal step can remove or collect particulate impurities or smear P by performing blowing, suction, or both on the surface of the workpiece 10.

[0105] The aforementioned control step is a step of checking and controlling the machining parameters.

[0106] The aforementioned machining parameters may include the positional alignment of the workpiece 10, confirmation of the alignment mark key, the height of the etching target on the workpiece 10, and machining drawing data having machining objective data.

[0107] The control step can control the etching step to be performed on holes, pads, and lines in unit units.

[0108] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements by those skilled in the art, utilizing the basic concepts of the present invention as defined in the appended claims, also fall within the scope of the present invention. [Explanation of Symbols]

[0109] 10 Items to be processed 11 glass core 13 Metal layer 15. Insulating layer 100 stages 200 Control device 300 Laser Beam Generators 400 Optical transmission system 500 Blowing-Suction Device 600 Monitoring and Inspection Equipment 4005 Primary beam quality control system 4010 Diffraction Optics 4020 Circular Polarizing Unit L laser light P particulate impurities (particles), smear

Claims

1. The object to be processed, including the insulating layer, A stage on which the workpiece is placed, An optical transmission system arranged on the stage for transmitting laser light to the insulating layer, A laser beam generator connected to the aforementioned optical transmission system and outputting laser light, A blowing-suction device is disposed between the workpiece and the optical transmission system, A monitoring and inspection device for inspecting the surface shape of the workpiece, Includes a control device that controls the laser light generated from the laser beam generator or the optical transmission system, reflecting the surface shape information, The optical transmission system is a laser drilling system that controls the laser light using a diffraction optical system.

2. The laser drilling system according to claim 1, wherein the diffraction optical system applies a patterned quasi-binary phase mask.

3. The laser drilling system according to claim 1, wherein the optical transmission system filters the laser light into linear polarization, patterns it based on information provided by the control device using a diffraction optical system, and after partially different light intensities are realized, converts the linear polarization back into circular polarization and transmits it to the workpiece.

4. The aforementioned optical transmission system is A primary beam quality control system through which the laser light generated from the laser beam generator passes, A diffraction optical system in which light that has passed through the primary beam quality control system is modulated, The laser drilling system according to claim 1, further comprising a circular polarization unit that converts light passing through the diffractive optical system into circularly polarized light.

5. The aforementioned circular polarizing unit is A first circular polarizer through which light modulated by the diffraction optical system passes, A polarizing plate through which light that has passed through the first circular polarizing plate passes, The laser drilling system according to claim 4, further comprising a second circular polarizing plate through which light that has passed through the polarizing plate passes.

6. The diffraction optical system includes a spatial light modulator, The laser drilling system according to claim 1, wherein the spatial light modulator is provided with a liquid crystal that induces phase modulation and amplitude modulation of the laser light.

7. The laser drilling system according to claim 1, wherein the diffractive optical system includes a liquid crystal substrate spatial light modulator, a micromirror array-based spatial light modulator, a deformable mirror, or a diffractive optical element.

8. A placement step in which the object to be processed is placed on the stage, The process includes an etching step in which a primary laser beam output from a laser beam generator is passed through an optical transmission system to which a diffraction optical system is applied to convert it into a secondary laser beam, and the resulting laser beam is irradiated onto the workpiece. The object to be processed includes an insulating layer, A method for selectively removing an insulating layer, wherein the secondary laser beam removes a portion of the insulating layer at locations where a pattern including via holes, pads, lines, or all of these is formed in the insulating layer.

9. The etching step is, The primary processing step involves the primary laser light passing through a transmission optical system and a beam quality control device, The method for selectively removing an insulating layer according to claim 8, further comprising a secondary processing step of emitting the primary laser light as a secondary laser light whose pattern and intensity are adjusted according to the shape to be processed, after passing it through the diffraction optical system.

10. The etching step further includes a control process, The aforementioned control process is A process to confirm whether an abnormal intensity and shape of the order of zero occurs in the aforementioned diffraction optical system, The method for selectively removing an insulating layer according to claim 9, comprising the step of adjusting the abnormal strength and shape so that they are located on a dummy or pad in the workpiece.

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