Stepped through hole target structure, processing method, terminal and medium

Abstract

The invention discloses a stepped through hole target structure, a processing method, a terminal and a medium, and belongs to the technical field of IC carrier plates, the stepped through hole target structure comprises a through hole arranged on an IC carrier plate substrate, a first blind hole is synchronously processed above the through hole, a second blind hole is processed below the through hole, the first blind hole and the second blind hole are respectively positioned on the upper side surface and the lower side surface of the carrier plate, and the first blind hole and the second blind hole are respectively positioned on the upper side surface and the lower side surface of the carrier plate. The first blind hole and the second blind hole are coaxially arranged with the through hole, the aperture of the through hole is smaller than that of the first blind hole and that of the second blind hole, the aperture of the first blind hole is the same as that of the second blind hole, and the first blind hole and the second blind hole are used for optical alignment identification of the exposure machine. The upper blind hole and the lower blind hole which are coaxial and equal in hole diameter are matched with the through hole structure with the hole diameter smaller than that of the blind holes, penetrating transmission of interlayer geometric references is achieved, physical obstruction is formed through hole diameter difference, conducted interference of machining energy between layers is reduced, consistency and stability of double-face target recognition are guaranteed, and accurate alignment reference is provided for multilayer graph superposition.

Description

Technical Field

[0001] This invention relates to the field of IC substrate technology, and in particular to a stepped through-hole target structure, processing method, terminal and medium. Background Technology

[0002] Currently, IC substrates are a key carrier for high-density interconnect packaging, and the industry is moving towards multi-layering, thinning, and high-precision alignment. The IC substrate manufacturing process requires multiple layer stacking operations such as exposure, etching, drilling, and lamination. The geometric superposition accuracy of the circuit patterns of each layer directly determines the product yield and conductivity reliability.

[0003] Exposure machines and laser drilling equipment generally use optical alignment targets as a reference to ensure accurate matching of multi-layer patterns. However, as line spacing decreases to the micrometer level and the diversity of board thickness and number of layers increases, traditional single through-hole or blind hole targets are gradually failing to meet the mass production requirements of IC substrates in terms of recognition accuracy and interlayer penetration. In existing technologies, through-hole targets commonly used in the field directly penetrate the upper and lower layers with lasers to form a geometric reference, enabling interlayer penetration.

[0004] In the current process, the exposure target on side A is processed first, and then the exposure target on side B is processed until it is a through-hole target. The edge of the target on side A is easily affected by the laser energy of the target on side B processed later. This manifests as the edge of side A being burned and becoming blurred, affecting the positioning of the exposure target and thus causing accuracy errors. Summary of the Invention

[0005] To address the technical problem in the background art where existing laser drilling machines often process the target on side A first, and then process side B to form a through hole, the high-energy laser on the later-processed side easily ablates the edge area of ​​the first-processed side, affecting exposure alignment and recognition, this invention provides a stepped through-hole target structure, processing method, terminal, and medium.

[0006] The technical solution of this invention is as follows: This invention provides a stepped through-hole target structure, including a through-hole disposed on an IC substrate, a first blind hole being simultaneously machined above the through-hole, and a second blind hole being machined below the through-hole. The first blind hole and the second blind hole are respectively located on the upper and lower surfaces of the substrate. The first blind hole and the second blind hole are both coaxially disposed with the through-hole. The diameter of the through-hole is smaller than the diameter of the first blind hole and the second blind hole. The diameters of the first blind hole and the second blind hole are the same. The first blind hole and the second blind hole are used for optical alignment recognition in an exposure machine. The stepped through-hole target structure forms an independent double-sided optical recognition area through the coaxial design and differential aperture layout of through holes and upper and lower blind holes. The through holes serve as a through-layer reference to ensure the consistency of multi-layer stacking. The larger aperture blind holes provide a clear recognition outline while avoiding the direct effect of post-processing lasers on the edges of the formed target, keeping the edges of the double-sided target intact and sharp, significantly improving the accuracy of the exposure machine's alignment and gripping. The coaxial upper and lower blind holes with equal apertures allow the exposure machine to obtain a uniformly sized recognition target from either side of the carrier plate. Combined with the through-hole structure with an aperture smaller than that of the blind holes, it not only achieves the through-transmission of inter-layer geometric references but also forms a physical barrier through aperture differences, reducing the transmission interference of processing energy between layers, ensuring the consistency and stability of double-sided target recognition, and providing a precise alignment reference for multi-layer graphic stacking. Preferably, an energy attenuation transition zone is provided at the connection between the through hole and the first blind hole and the second blind hole. The energy attenuation transition zone has a smooth arc-shaped contour, which enables the laser energy to be gradient transferred at the interface between the through hole and the blind hole, avoiding edge ablation caused by sudden energy changes. At the same time, it optimizes the geometry of the hole wall, reduces shadow interference during optical recognition, makes the target edge imaging more continuous and clear, improves the accuracy of the exposure machine in capturing edge features, and further ensures the geometric consistency of interlayer alignment.

[0007] Preferably, the energy attenuation transition zone on the upper surface of the carrier plate is formed by a composite laser in one step, while the energy attenuation transition zone on the lower surface of the carrier plate is formed by a secondary positioning process. The one-step forming process of the upper surface transition zone reduces the accumulation of errors caused by the processing steps, ensuring a more precise connection between the through hole and the upper blind hole. The secondary positioning process on the lower surface can correct the deviation according to the actual center of the through hole, so that the shape of the upper and lower transition zones remains symmetrical and uniform. This not only improves the overall geometric accuracy of the structure, but also enhances the stability of the energy attenuation effect, providing balanced optical performance for double-sided recognition.

[0008] Preferably, the bottom surfaces of the first and second blind holes are provided with a reflective layer or a copper plating layer, and the edges of the openings of the first and second blind holes are provided with an anti-corrosion protective layer or an anti-oxidation coating. The reflective layer or copper plating layer at the bottom of the hole can significantly improve the signal strength and contrast of optical recognition, allowing the exposure machine to quickly and accurately capture the target position. The anti-corrosion or anti-oxidation coating at the opening can isolate the acid and alkali environment and oxidation factors in subsequent processes, avoiding problems such as corrosion and discoloration at the target edge, maintaining the optical performance and structural integrity of the target for a long time, and ensuring the recognition stability and consistency during mass production.

[0009] A processing method, comprising: Step 1: Determine the initial center point of the target on the IC carrier board and establish an upper and lower coaxial coordinate system to provide a unified reference framework for subsequent processing. This ensures that the processing of through holes and upper and lower blind holes revolves around the same core positioning, reducing positioning deviations from the source and laying the foundation for precise interlayer alignment. Step 2: Composite laser forming of through holes and the first blind hole in one step. The composite laser forming of through holes and the upper blind hole is realized simultaneously, which improves the processing efficiency and avoids the secondary positioning error caused by step processing. The synergistic effect of the central strong energy beam and the outer weak energy beam can not only ensure the penetration of the through hole, but also accurately control the forming quality of the upper blind hole, and can also simultaneously form an energy attenuation transition zone, which improves the processing efficiency while ensuring the structural accuracy. Step 3: Re-measure and position the center of the through hole and process the second blind hole. The re-measurement and positioning of the center of the through hole can correct the coordinate drift caused by factors such as thermal expansion and contraction during the processing in real time, so that the processing reference of the second blind hole is consistent with the actual center of the through hole, ensuring that the upper and lower blind holes are strictly coaxial with the through hole. Combined with specific processing paths and energy control, the overall geometric accuracy and recognition performance of the target structure are further improved. Step 4: Surface metallization treatment. Surface metallization treatment optimizes the optical reflection characteristics and structural stability of the bottom of the blind hole through an annealing process of depositing a reflective layer or copper plating layer. This allows the exposure machine to obtain a stronger recognition signal, while also improving the adhesion between the plating layer and the substrate, enhancing the environmental resistance of the target, and ensuring stable alignment accuracy during multiple stacking processes.

[0010] Preferably, in step 2, a coaxially superimposed composite laser beam is used. The center of the composite laser beam is a small-diameter high-energy beam, and the periphery is a large-diameter low-energy beam. The laser head moves vertically downward along the Z-axis from above the carrier plate, drilling through the carrier plate in one go. This allows the central high-energy beam to directly ablate the entire thickness of the carrier plate material to form a through hole. At the same time, the peripheral low-energy beam ablates the surface material of the upper surface of the carrier plate to form a first blind hole. An energy attenuation transition zone is simultaneously formed at the connection between the through hole and the first blind hole. The coaxially superimposed composite laser beam achieves the synchronous formation of the through hole and the upper blind hole through the differential setting of energy density. The central high-energy beam ensures the penetration and hole wall quality of the through hole, while the peripheral low-energy beam precisely controls the depth and contour of the upper blind hole. The energy attenuation transition zone formed synchronously under the synergistic effect of the two does not require additional processing steps. This simplifies the process flow, avoids interface defects that may occur in step-by-step processing, and improves the integrity of the structure and processing efficiency.

[0011] Preferably, in step 3, after the through hole is processed, three feature points are evenly selected on the edge of the through hole and the coordinates of the three feature points are measured. The actual center coordinates of the through hole are calculated based on the three feature points. After the actual center coordinates of the through hole are determined, the coordinate drift is calculated, and the coordinate system is corrected based on the actual center coordinates of the through hole so that the machining datum of the second blind hole is consistent with the actual center coordinates of the through hole. After the coordinate system is corrected, the second blind hole is machined along the corrected center point.

[0012] The three-point positioning method, through the measurement of evenly distributed feature points and the calculation of the center, can accurately obtain the actual center coordinates of the through hole, effectively offsetting the possible errors of a single measuring point. After correcting the coordinate system based on these coordinates, the machining datum of the second blind hole is completely aligned with the actual center of the through hole, completely eliminating the influence of coordinate drift caused by factors such as thermal expansion and contraction, ensuring that the coaxiality of the upper and lower blind holes and the through hole meets the high-precision requirements, and providing a solid guarantee for the accurate matching of multi-layer graphics.

[0013] Preferably, the processing path of the second blind hole adopts a spiral scanning from the outside to the inside, and the laser energy decreases along the processing path during the processing. The spiral scanning path from the outside to the inside, combined with the laser energy reduction setting, allows the outer edge of the second blind hole to obtain sufficient energy to ensure the forming quality. The energy gradually decreases on the inner side near the through hole, achieving a smooth connection with the through hole interface, reducing ablation and step defects caused by local energy concentration, improving the surface smoothness of the hole wall, making the target edge clearer, and further optimizing the accuracy of exposure recognition.

[0014] A terminal, characterized in that it comprises: Memory, used to store the machining program for the stepped through-hole target structure; A processor for performing the steps of the above-described processing method when executing a stepped through-hole target structure.

[0015] The terminal stores standardized processing programs in its memory to ensure the consistency and repeatability of the processing technology. The processor controls and adjusts parameters in real time during the processing, and can accurately execute key steps such as composite laser processing, center retesting, and energy control. This effectively avoids errors caused by manual operation, improves processing efficiency and product yield, and provides stable and reliable equipment support for the mass production of stepped through-hole targets.

[0016] A computer-readable storage medium is provided for storing computer instructions. When a computer reads the computer instructions in the storage medium, the computer executes the aforementioned processing method. The standardized computer instructions stored in the computer-readable storage medium ensure the uniform execution of the processing method on different devices, avoid the dispersion of process parameters, and ensure that the processing of each batch of targets follows consistent precision standards and process specifications, thereby improving product consistency and stability. At the same time, it facilitates process updates and iterations and the large-scale promotion of mass production.

[0017] As can be seen from the above technical solutions, the advantages of the present invention are: 1. The stepped through-hole target structure forms an independent double-sided optical recognition area through the coaxial design and differential aperture layout of through holes and upper and lower blind holes. The through holes serve as a through-layer reference to ensure the consistency of multi-layer stacking. The larger aperture blind holes provide a clear recognition outline while avoiding the direct effect of post-processing laser on the edge of the formed target, keeping the edge of the double-sided target intact and sharp, significantly improving the accuracy of the exposure machine's alignment and gripping. The coaxial upper and lower blind holes with equal apertures allow the exposure machine to obtain a uniformly sized recognition target from either side of the carrier plate. Combined with the through-hole structure with a smaller aperture than the blind holes, it not only achieves the through-transmission of inter-layer geometric references but also forms a physical barrier through aperture differences, reducing the transmission interference of processing energy between layers, ensuring the consistency and stability of double-sided target recognition, and providing a precise alignment reference for multi-layer graphic stacking.

[0018] 2. By using composite laser to synchronously form through holes, the first blind hole, and the upper energy transition zone, the three are physically-level absolutely concentric. The coordinate deviation is then corrected by re-measuring the center of the through hole to ensure that the second blind hole is precisely aligned with the through hole, which greatly improves the overall coaxial accuracy. The stepped hole diameter and synchronous processing logic isolate the energy interference of the laser in the later processing on the target of the earlier processing side, so that the edges of the double-sided blind hole remain intact and clear, optimize the exposure recognition effect, simplify the process and improve efficiency through synchronous processing, and adapt to various deviations in the processing process through secondary positioning, taking into account processing accuracy, efficiency and mass production reliability. Attached Figure Description

[0019] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the stepped through-hole target structure according to one or more embodiments of the present invention; Figure 2 This is a step diagram illustrating the processing method of the stepped through-hole target structure according to one or more embodiments of the present invention; The components represented by the various reference numerals in the diagram are: 1. Through hole; 2. First blind hole; 3. Second blind hole; 4. Energy attenuation transition zone. Detailed Implementation

[0021] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0022] Example 1 In a typical embodiment of the present invention, such as Figure 1 As shown, a stepped through-hole target structure is proposed, including: a through-hole 1 disposed on a carrier plate substrate and a first blind hole 2 and a second blind hole 3 located on the upper and lower surfaces of the carrier plate; the through-hole 1 penetrates the carrier plate, the first blind hole 2 is located on the upper surface of the carrier plate, and the second blind hole 3 is located on the lower surface of the carrier plate, and both the first blind hole 2 and the second blind hole 3 are coaxially disposed with the through-hole 1.

[0023] In this embodiment, the diameter of the through hole 1 is smaller than the diameter of the first blind hole 2 and the second blind hole 3. The through hole 1, the first blind hole 2 and the second blind hole 3 are coaxially arranged. The diameters of the first blind hole 2 and the second blind hole 3 are the same. The first blind hole 2 and the second blind hole 3 are used for optical alignment identification of the exposure machine. The through hole 1 is used for interlayer geometric reference to pass through, which facilitates the coaxial alignment and positioning of the first blind hole 2 and the second blind hole 3.

[0024] In actual implementation, the IC substrate can be made of BT resin-based or ABF resin-based materials. The first blind hole 2 and the through hole 1 penetrating the substrate are simultaneously processed on the substrate using a high-precision laser drilling device. Then, the second blind hole 3 is formed on the underside of the substrate using a relatively low laser power.

[0025] In this embodiment, the aperture of the through hole 1 is 0.8-1.2 mm, and the apertures of the first blind hole 2 and the second blind hole 3 are 1.4-1.8 mm. This balances interlayer connectivity and optical recognition effect. The size of the through hole 1 is controlled at around 1 mm, which can achieve high-precision penetration while ensuring the integrity of the carrier plate structure. The aperture of the blind hole is slightly larger than that of the through hole 1, which makes the reflective surface of the exposure machine recognition area wider and the recognition contrast higher.

[0026] like Figure 1 As shown, an energy attenuation transition zone 4 is provided at the connection between the hole wall of the through hole 1 and the first blind hole 2 and the second blind hole 3. The energy attenuation transition zone 4 has a smooth arc-shaped profile, a width of 50±5μm, and a surface roughness Ra≤0.3μm. The energy attenuation transition zone 4 on the upper surface of the carrier plate is formed by composite laser in one step, and the energy attenuation transition zone 4 on the lower surface of the carrier plate is formed by secondary positioning processing.

[0027] The bottom surfaces of the first blind via 2 and the second blind via 3 are provided with a reflective layer or a copper plating layer. During implementation, the bottom surfaces of the first blind via 2 and the second blind via 3 can be first subjected to plasma cleaning and surface activation, and then a metal reflective layer can be deposited using physical vapor deposition. The reflective layer can be made of materials such as aluminum, silver, nickel, or chromium, with a thickness controlled between 0.2 and 0.5 μm to obtain stable high reflectivity. If a copper plating process is used, a uniform copper layer of approximately 1 μm can be formed at the bottom of the via. This layer not only enhances the intensity of reflected light but also provides a conductive interface for subsequent copper plating or electroplating. Reflectivity testing shows that the average reflectivity of the area at the bottom of the via after deposition reaches over 90%, significantly improving the signal strength for the exposure machine. Long-term damp heat testing shows that the plating layer is firmly bonded, with no peeling, oxidation, or darkening, ensuring the stability of recognition in mass production.

[0028] The edges of the first blind hole 2 and the second blind hole 3 are provided with an anti-corrosion protective layer or an anti-oxidation coating. The anti-corrosion protective layer can be made of silicone anti-corrosion coating or fluorinated resin-based anti-oxidation material. The anti-oxidation coating can effectively isolate the acid and alkali etching solution in the wet process, prevent the metal layer at the hole from being corroded or oxidized and discolored, thereby maintaining the optical recognition contrast of the target.

[0029] Example 2 In another typical embodiment of the present invention, such as Figure 2 As shown, a method for fabricating a stepped through-hole target structure is proposed, including: Step 1: Determine the initial center point of the target on the IC carrier and establish a coaxial coordinate system. Specifically, a high-precision optical alignment system is used to scan the target area of ​​the IC carrier board. The positioning accuracy of the high-precision optical alignment system is ±5μm. Three pre-positioning markers are initially identified, which are evenly distributed and arranged in an equilateral triangle with a side length ≥5mm. The coordinates of the initial center point are then calculated. ; Turn on the temperature control system of the carrier worktable to stabilize the carrier temperature at 25±3℃ and reduce the impact of temperature fluctuations on subsequent processing. A multi-point uniform adsorption fixation method is adopted, with adsorption points distributed in a matrix and a spacing of ≤20mm between adsorption points. The adsorption pressure is 0.03~0.05MPa, which ensures uniform stress on the carrier plate and suppresses micro-deformation during processing, so that the deformation is ≤3μm. Using a dual-lens coaxial calibration system, an upper and lower coaxial coordinate system is established with the initial center point as the origin. The Z-axis of the upper and lower coaxial coordinate system is the laser processing axis, and the calibration error is ≤2μm.

[0030] Step 2: Composite laser forming of through hole 1 and the first blind hole 2 in the upper layer in one step; Specifically, a coaxially superimposed composite laser beam is used, with a small-diameter, high-energy beam at the center of the composite laser beam, and a spot diameter of... The first laser energy density is 0.1–0.2 mm. 8–12 J / cm 2 The outer perimeter consists of a large-diameter, low-energy beam with a spot diameter of [missing information]. The second laser energy density is 1.4–1.8 mm. 2-4 J / cm 2 .

[0031] The laser head moves vertically downwards along the Z-axis from above the carrier plate, focusing on the initial center point. The drill penetrates the carrier plate in a single pass, allowing the central high-energy beam to directly ablate the entire thickness of the carrier plate, thus creating a hole. A through-hole 1 with a diameter of 0.8–1.2 mm is formed; simultaneously, a weak energy beam from the periphery ablates the surface material on the upper surface of the carrier plate to a depth of 0.1–0.2 mm, forming a hole with a diameter of 0.8–1.2 mm. The first blind hole 2 is 1.4 to 1.8 mm.

[0032] The energy distribution of the composite laser follows a Gaussian superposition model, expressed as follows:

[0033] Where r is the radial position of the laser beam, 0≤r≤r2; r1 is the radius of the central beam, r1=D1 / 2; r2 is the radius of the outer beam, r2=D2 / 2, so that the energy attenuation transition zone is formed synchronously at the connection between the through hole 1 and the first blind hole 2 in the upper layer, without the need for additional processing.

[0034] Step 3: Re-measure and position the center of through hole 1 and machine the second blind hole 3; Specifically, after the through hole 1 is machined, a three-point positioning re-measurement is performed using a laser displacement sensor. Three feature points are evenly selected on the edge of the through hole 1, namely points A, B, and C. The included angle between adjacent feature points is 120°. The coordinates of the three feature points are measured as follows: , and The actual center coordinates of through hole 1 were calculated based on the three-point centering formula. .

[0035] The formula for finding the center of a circle using three points is:

[0036]

[0037] After the actual center coordinates of through hole 1 are determined, the coordinate drift is calculated based on the actual center coordinates of through hole 1. Correct the coordinate system to ensure that the machining datum of the second blind hole 3 in the lower layer is consistent with the actual center coordinates of the through hole 1.

[0038] The formula for calculating the coordinate drift is as follows:

[0039]

[0040] After the coordinate system is corrected, a third laser energy is used, with an energy density E3 of 3–5 J / cm² and a spot diameter D3 of 1.4–1.8 mm. The second blind hole 3 is machined along the corrected center point. The machining path uses a spiral scan from the outside in, with the third laser energy decreasing progressively. The pitch is 0.05–0.1 mm, and the scanning speed is 50–80 mm / s. The spiral scan from the outside in, combined with the decreasing laser energy, ensures that the outer edge of the blind hole 1 receives sufficient energy to remove material, while the energy gradually decreases towards the inner side of the through hole 1, naturally forming a smooth energy attenuation transition zone and avoiding step differences or ablation on the hole wall. The continuous and non-overlapping laser action area during the scanning process reduces local heat accumulation and prevents carbonization, delamination, or cracking of the substrate due to high temperatures. It also protects the edges of the processed through-hole 1 from secondary ablation. Furthermore, the spiral path converges from the outer edge to the center point, precisely fitting the coaxial design of through-hole 1 and the second blind hole 3, reducing processing deviations, ensuring strict concentricity between the second blind hole 3 and through-hole 1, and guaranteeing the consistency of the interlayer alignment reference. At the same time, the continuous cutting mode of spiral scanning reduces the surface roughness of the hole wall, making the edges of the second blind hole 3 complete and clear, and improving the contrast and stability of the optical recognition of the exposure machine.

[0041] Step 4: Surface metallization treatment.

[0042] During surface pretreatment, the carrier plate is immersed in a 5%–10% neutral cleaning agent solution and ultrasonically cleaned at 300W power for 10 minutes to remove laser processing residues and impurity particles from the bottom and edges of the holes. The carrier plate is then soaked in a 10%–15% dilute hydrochloric acid solution for 5 minutes to remove oxides from the bottom surface of the holes, followed by rinsing with deionized water until pH=7. Finally, plasma treatment is performed to improve the adhesion of the bottom surface of the holes. A thin film of reflective material is deposited on the pretreated bottom surface of the hole. The reflective material is selected from aluminum, silver, chromium, nickel and their binary or multi-element alloys, and is formed by physical vapor deposition or chemical vapor deposition process. After deposition, annealing is performed in a vacuum or inert atmosphere. The inert atmosphere is nitrogen or argon, with an oxygen volume fraction of no more than 50 ppm. The annealing temperature is controlled between 150°C and 250°C, and the time is between 15 minutes and 30 minutes.

[0043] Example 3 In another typical embodiment of the present invention, a terminal is provided, comprising: Memory, used to store the machining program for the stepped through-hole target structure; A processor is used to execute the steps of a method for processing a stepped through-hole target structure.

[0044] Example 4 In another typical embodiment of the present invention, a computer-readable storage medium is proposed, which stores computer instructions. When the computer reads the computer instructions in the storage medium, the computer executes a method for processing a stepped through-hole target structure.

[0045] It is understood that the systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer, which can be a personal computer, a laptop computer, a personal digital assistant, a tablet computer, a wearable device, or any combination of these devices.

[0046] In a typical configuration, a computer includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0047] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0048] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0049] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A stepped through-hole target structure, comprising: The through hole (1) set on the substrate is characterized in that a first blind hole (2) is simultaneously processed above the through hole (1), and a second blind hole (3) is processed below the through hole (1). The first blind hole (2) and the second blind hole (3) are respectively located on the upper and lower surfaces of the substrate. The first blind hole (2) and the second blind hole (3) are both coaxially arranged with the through hole (1). The diameter of the through hole (1) is smaller than the diameter of the first blind hole (2) and the second blind hole (3). The diameters of the first blind hole (2) and the second blind hole (3) are the same. The first blind hole (2) and the second blind hole (3) are used for optical alignment recognition of the exposure machine.

2. The stepped through-hole target structure according to claim 1, characterized in that, An energy attenuation transition zone (4) is provided at the connection between the through hole (1) and the first blind hole (2) and the second blind hole (3), and the energy attenuation transition zone (4) has a smooth arc-shaped profile.

3. The stepped through-hole target structure according to claim 2, characterized in that, The energy attenuation transition zone (4) on the upper surface of the carrier plate is formed by composite laser in one step, and the energy attenuation transition zone (4) on the lower surface of the carrier plate is formed by secondary positioning processing.

4. The stepped through-hole target structure according to claim 1, characterized in that, The bottom surfaces of the first blind hole (2) and the second blind hole (3) are provided with a reflective layer or a copper plating layer, and the edges of the openings of the first blind hole (2) and the second blind hole (3) are provided with an anti-corrosion protective layer or an anti-oxidation coating.

5. A processing method for processing the stepped through-hole target structure as described in any one of claims 1-4, characterized in that, Processing methods include: Step 1: Determine the initial center point of the target on the carrier plate and establish a coaxial coordinate system. Step 2: Composite laser forming of through hole (1) and first blind hole (2) in one step; Step 3: Re-measure and position the center of the through hole (1) and machine the second blind hole (3); Step 4: Surface metallization treatment.

6. The processing method according to claim 5, characterized in that, In step 2, a coaxial superimposed composite laser beam is used. The center of the composite laser beam is a small-diameter high-energy beam, and the periphery is a large-diameter low-energy beam. The laser head moves vertically downward along the Z-axis from above the carrier plate and drills through the carrier plate in one go, so that the central high-energy beam directly ablates the entire thickness of the carrier plate material to form a through hole (1). At the same time, the peripheral low-energy beam ablates the surface material on the upper surface of the carrier plate to form a first blind hole (2). The energy attenuation transition zone (4) is formed simultaneously at the connection between the through hole (1) and the first blind hole (2).

7. The processing method according to claim 5, characterized in that, In step 3, after the through hole (1) is processed, three feature points are evenly selected on the edge of the through hole (1) and the coordinates of the three feature points are measured. The actual center coordinates of the through hole (1) are calculated based on the three feature points. After the actual center coordinates of the through hole (1) are determined, the coordinate drift is calculated, and the coordinate system is corrected based on the actual center coordinates of the through hole (1) so that the machining datum of the second blind hole (3) is consistent with the actual center coordinates of the through hole (1); After the coordinate system is corrected, the second blind hole (3) is machined along the corrected center point.

8. The processing method according to claim 7, characterized in that, The processing path of the second blind hole (3) adopts a spiral scanning from the outside to the inside, and the laser energy decreases along the processing path during the processing.

9. A terminal, characterized in that, include: Memory, used to store the machining program for the stepped through-hole target structure; A processor for executing the steps of the processing method as described in claim 5 when performing a stepped through-hole target structure.

10. A computer-readable storage medium, characterized in that, Used to store computer instructions, when the computer reads the computer instructions from the storage medium, the computer executes the processing method as described in claim 5.

Images