Method for forming substrate with conductive pillar

Abstract

A method for forming a substrate with conductive pillar is provided. The method includes: drilling a substrate to be processed using a drilling laser to form a plurality of holes, having a first aperture, on the substrate to be processed; expanding the plurality of holes through a hole expansion laser or an etching process so that the plurality of holes have a second aperture which is larger than the first aperture, and a surface roughness of the inner wall of the plurality of holes is reduced to

Description

Method for forming a substrate with conductive pillars The present invention relates to a method for forming a substrate, and more particularly to a method for forming a substrate having conductive pillars. With the advancement of technology, semiconductor manufacturing processes have become increasingly precise. As the dimensions of substrates become more and more refined, the current methods for filling conductive pillars are less efficient and are gradually failing to meet the demands of advanced semiconductor packaging processes for the transfer of a large number of conductive pillars. Therefore, how to improve the filling efficiency of conductive posts through methodological improvements and overcome the above-mentioned defects has become one of the important issues that this project aims to address. The technical problem to be solved by the present invention is to provide a method for forming a substrate with conductive pillars, which addresses the shortcomings of the prior art. The method includes: drilling a substrate to be processed using a drilling laser to form a plurality of holes on the substrate, the plurality of holes having a first aperture; enlarging the plurality of holes using a hole-enlarging laser or an etching process to give the plurality of holes a second aperture larger than the first aperture, and reducing the surface roughness of the inner walls of the plurality of holes to 10 nm to 50000 nm; filling the plurality of conductive pillars into the plurality of holes having the second aperture; filling the plurality of holes with a colloid to fill the gap between the plurality of conductive pillars and the inner walls of the plurality of holes, to obtain a substrate semi-finished product; and polishing the substrate semi-finished product to obtain a substrate with conductive pillars. In a feasible or preferred embodiment of the present invention, the first aperture is between 1 µm and 10 µm, and the second aperture is between 10 µm and 100 µm. In a feasible or preferred embodiment of the present invention, the wavelength of the drilling laser is 300 nm to 2000 nm, the pulse width of the drilling laser is 50 fs to 500 fs, and the pulse energy of the drilling laser is 10 nJ to 1000 µJ. In a feasible or preferred embodiment of the present invention, the wavelength of the aperture-enlarging laser is 300 nm to 2000 nm, the pulse width of the aperture-enlarging laser is 50 fs to 500 fs, and the pulse energy of the aperture-enlarging laser is 10 nJ to 1000 µJ. In a feasible or preferred embodiment of the present invention, the etching process includes etching a substrate to be processed with holes having a first aperture using an acidic or alkaline material. The acidic material includes hydrogen fluoride, and the alkaline material includes potassium hydroxide. In a feasible or preferred embodiment of the present invention, the substrate to be processed has an upper surface and a lower surface. The method of forming a substrate with conductive pillars further includes a protective treatment of the substrate to be processed before drilling, which includes: temporarily fixing a protective plate element to the upper or lower surface of the substrate to be processed using a clamping element; or providing a protective material to the substrate to be processed to form a protective layer on the upper or lower surface of the substrate to be processed. In a feasible or preferred embodiment of the present invention, the method of forming a substrate having conductive pillars further includes using a monitoring module to monitor the state of the gap between the plurality of conductive pillars and the inner walls of the plurality of holes, and the monitoring module includes a camera unit. In a feasible or preferred embodiment of the present invention, the method of forming a substrate with conductive pillars further includes monitoring the substrate to be processed using a monitoring module. The monitoring module includes an optical module and an image analysis module. The image analysis module is electrically connected to the optical module. The optical module includes a light emitting unit and a light receiving unit. The light emitting unit emits a monitoring laser toward the substrate to be processed, the wavelength range of the monitoring laser being 300 nm to 2000 nm, and the pulse width range of the monitoring laser being 50 fs to 50 ns. In a feasible or preferred embodiment of the present invention, the light receiving unit includes a first light wavefront sensor and a second light wavefront sensor. The first light wavefront sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second light wavefront sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. In addition, the image analysis module includes a waveform generator electrically connected to a first optical wavefront sensor and a second optical wavefront sensor. The waveform generator is used to receive reflected light signals and transmitted light signals, and to generate a first detection waveform corresponding to the reflected light signal and a second detection waveform corresponding to the transmitted light signal. In a feasible or preferred embodiment of the present invention, the light receiving unit includes a first photoelastic sensor and a second photoelastic sensor. The first photoelastic sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second photoelastic sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. In addition, the image analysis module includes an image device electrically connected to a first photoelastic sensor and a second photoelastic sensor. The image device is used to receive reflected light signals and transmitted light signals, and to generate a first stress distribution feature map corresponding to the reflected light signal and a second stress distribution feature map corresponding to the transmitted light signal. In a feasible or preferred embodiment of the present invention, the light receiving unit includes a first laser vibrometer and a second laser vibrometer. The first laser vibrometer is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate reflected ultrasound. The second laser vibrometer is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate transmitted ultrasound. In addition, the image analysis module includes a waveform generator, which is electrically connected to a first laser vibrometer and a second laser vibrometer. The waveform generator is used to receive reflected ultrasound waves and transmitted ultrasound waves, and to generate a first waveform corresponding to the reflected ultrasound waves and a second waveform corresponding to the transmitted ultrasound waves. In a feasible or preferred embodiment of the present invention, the light receiving unit includes a first hyperspectral sensor and a second hyperspectral sensor. The first hyperspectral sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second hyperspectral sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. The first and second hyperspectral sensors receive spectral ranges from 300 nm to 2500 nm, and the spectra are continuous. In addition, the image analysis module includes a hyperspectral generator, which is electrically connected to a first hyperspectral sensor and a second hyperspectral sensor. The hyperspectral generator is used to receive reflected light signals and transmitted light signals, and to generate a first detection spectrum corresponding to the reflected light signal and a second detection spectrum corresponding to the transmitted light signal. In a feasible or preferred embodiment of the present invention, the monitoring module further includes an image detection device electrically connected to the image analysis module. The image detection device is configured to detect and capture multiple images of a shadowed area of ​​the substrate to be processed that has not been subjected to monitoring laser. The image analysis module is used to receive the multiple images and, based on the multiple images, determine and calculate the defects and probabilities present in the shadowed area, or compensate for the multiple images and determine and calculate the defects and probabilities present in the shadowed area. One of the beneficial effects of the present invention is that the method for forming a substrate with conductive pillars provided by the present invention can increase the aperture of the plurality of holes in the substrate to be processed by using a "hole-expanding laser or an etching process to perform a hole-expanding treatment on a plurality of holes", and reduce the surface roughness of the inner wall of the holes or improve the smoothness of the inner wall of the holes, thereby improving the filling efficiency of the conductive pillars and improving the quality of the substrate with conductive pillars formed. To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. The following specific embodiments illustrate the implementation of the "method for forming a substrate with conductive pillars" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. Furthermore, the accompanying drawings of this invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention. It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein may, as appropriate, include any combination of one or more of the associated listed items. [First Embodiment] Please refer to Figure 1, which illustrates the flow steps of a method for forming a substrate with conductive pillars according to a first embodiment of the present invention. As shown in Figure 1, the method for forming a substrate with conductive pillars according to the present invention includes: step S101, drilling a substrate to be processed using a drilling laser to form a plurality of holes having a first aperture on the substrate to be processed; step S102, enlarging the plurality of holes having the first aperture using a hole-enlarging laser or an etching process to give the plurality of holes a second aperture; step S103, filling the plurality of conductive pillars into the plurality of holes having the second aperture; step S104, filling the plurality of holes with a colloid to fill the gap formed between the plurality of conductive pillars and the inner walls of the plurality of holes, to obtain a substrate semi-finished product; and step S105, grinding the substrate semi-finished product to obtain a substrate with conductive pillars. Referring to Figures 1 and 2, in step S101, the drilling laser device 1 can use a drilling laser L1 to drill a hole in the substrate 10 to be processed, thereby forming a hole 11 with a first aperture D1 on the substrate 10. Furthermore, according to some embodiments, for better drilling performance, the wavelength of the drilling laser L1 can be from 300 nm to 2000 nm (e.g., any positive integer between 300 nm and 2000 nm), the pulse width of the drilling laser L1 can be from 50 fs to 500 fs (e.g., any positive integer between 50 fs and 500 fs), and the pulse energy of the drilling laser L1 can be from 10 nJ to 1000 µJ (e.g., any positive integer between 10 nJ and 1000 µJ). Please refer to Figures 1 and 3. Figure 3 is a schematic cross-sectional view of the substrate to be processed after step S102. To improve the efficiency of subsequent conductive pillar filling and the quality of the resulting substrate with conductive pillars, in step S102, a hole 11 with a first aperture D1 can be enlarged using a hole-enlarging laser or etching process to give the hole 11 a second aperture D2. According to some embodiments, the first aperture D1 is between 1 µm and 10 µm (e.g., any positive integer between 1 µm and 10 µm), and the second aperture D2 is between 10 µm and 100 µm (e.g., any positive integer between 10 µm and 100 µm). According to some embodiments, the aperture enlargement process in step S102 can, for example, use an aperture enlargement laser device (not shown in the figure) to emit an aperture enlargement laser onto the aperture 11 having a first aperture diameter D1, so as to reduce the surface roughness of the inner wall of the aperture 11 and give the aperture 11 a second aperture diameter D2 larger than the first aperture diameter D1. According to some embodiments, in order to achieve a better aperture enlargement effect, the wavelength of the aperture enlargement laser can be from 300 nm to 2000 nm (e.g., any positive integer between 300 nm and 2000 nm), the pulse width of the aperture enlargement laser can be from 50 fs to 500 fs (e.g., any positive integer between 50 fs and 500 fs), and the pulse energy of the aperture enlargement laser can be from 10 nJ to 1000 µJ (e.g., any positive integer between 10 nJ and 1000 µJ). Furthermore, according to other embodiments, the hole enlargement process in step S102 can also be, for example, using an etching process to enlarge the hole 11, thereby reducing the surface roughness of the inner wall of the hole 11 and giving the hole 11 a second aperture D2 larger than the first aperture D1. According to some embodiments, the etching process may include etching the hole 11 with an acidic or alkaline material. For example, the etching process may be wet etching, which may include applying an acidic or alkaline solution to the substrate 10 to be processed to remove a portion of the substrate 10 and enlarge the hole 11 of the substrate 10. Preferably, the acidic solution may be, for example, hydrofluoric acid containing hydrogen fluoride (HF), and the alkaline solution may be, for example, an aqueous solution of potassium hydroxide containing potassium hydroxide (KOH). Furthermore, in order to ensure that the finished substrate with conductive pillars has better quality, in some embodiments, the surface roughness of the inner wall of the hole 11 obtained by the hole enlargement process in step S102, as measured by a surface roughness meter, is between 10 nm and 50,000 nm (for example, any positive integer between 10 nm and 50,000 nm). Referring to Figures 1 and 4, in step S103, the conductive post 20 can be filled into the hole 11 having a second aperture D2. For example, the substrate 10 to be processed, which has undergone drilling and hole enlargement processing, can be placed on a vibratory feeder (not shown in the figure), and the conductive post 20 can be placed on the substrate 10. Then, the vibratory feeder is repeatedly vibrated in a horizontal or vertical direction to move the conductive post 20 on the substrate 10 and fill the hole 11. Furthermore, according to some embodiments, before performing step S103, an adhesive layer 30 may be attached to the bottom of the substrate 10 to be processed, as needed. This allows the conductive posts 20 filling the holes 11 to be fixed in the substrate 10 during step S103. In practical applications, the material of the adhesive layer 30 may include epoxy resin, β-staged bisbenzocyclobutene (BCB), silicone, perfluorocyclobutane (PFCB), or polyimide. Referring to Figure 1, in step S104, the colloid 40 can be filled into the hole 11 to fill the gap between the conductive post 20 and the inner wall of the hole 11, and the conductive post 20 is fixed in the hole 11 to obtain the substrate semi-finished product S1. Specifically, step S104 may include applying the colloid 40 to the substrate 10 to be processed by spin coating, filling the gap between the conductive post 20 and the inner wall of the hole 11 with the colloid 40, and then heating the colloid 40 to form spin-on glass (SOG) on the substrate 10 to be processed, and obtaining the substrate semi-finished product S1 as shown in Figure 4. After completing step S104, the adhesive layer 30 can be removed, and then step S105 is performed, which includes grinding the upper and lower surfaces of the substrate semi-finished product S1. As shown in Figure 6, after grinding in step S105, a substrate S2 finished product with a flat surface and conductive pillars can be obtained. In addition, please refer to Figures 4 and 5. According to some embodiments, steps S101 to S104 may include using a monitoring module 50 to monitor the substrate 10 to be processed in real time, including monitoring the formation status of the holes 11 on the substrate 10 to be processed, the filling status of the conductive pillars 20, and the status of the gap between the conductive pillars 20 and the inner wall of the holes 11. Specifically, referring to Figure 4, the monitoring module 50 may include a camera unit 56, which can be used to monitor the gap between the conductive post 20 and the inner wall of the hole 11 to confirm the filling status of the colloid 40. In practical applications, the camera unit 56 may be, for example, a CCD monitoring camera or a CMOS monitoring camera. Furthermore, referring to Figure 5, according to some embodiments, the monitoring module 50 further includes a light emitting unit 51, a control device 52, an imaging device 53, a first light receiving unit 54, and a second light receiving unit 55. The light emitting unit 51, the imaging device 53, the first light receiving unit 54, and the second light receiving unit 55 are all electrically connected to the control device 52. The light emitting unit 51 is located on the first side of the substrate 10 to be processed and emits a monitoring laser Lm toward the substrate 10. The first light receiving unit 54 is located on the first side of the substrate 10 to receive the reflected light La from the monitoring laser Lm reflected by the substrate 10 to generate a reflected light signal. The second light receiving unit 55 is located on the second side of the substrate 10 to receive the transmitted light Lb from the monitoring laser Lm passing through the substrate 10 to generate a transmitted light signal. The imaging device 53 is electrically connected to the first light receiving unit 54 and the second light receiving unit 55 to receive the reflected light La and the transmitted light Lb, and generate a detection result. The monitoring module 50 may also include a moving device (not shown in the figure). For example, a first light receiving unit 54 is connected to a first moving device so that the first light receiving unit 54 can move in three-dimensional space; a second light receiving unit 55 is connected to a second moving device so that the second light receiving unit 55 can move in three-dimensional space; and a light emitting unit 51 is connected to a laser moving device so that the light emitting unit 51 can move in three-dimensional space. This allows adjustment of the light emission position of the light emitting unit 51 and the light receiving positions of the first light receiving unit 54 and the second light receiving unit 55. In one embodiment, the monitoring module 50 is a hyperspectral monitoring module, which includes an optical module and an image analysis module (not shown in the figure). The optical module is electrically connected to the image analysis module and includes a light emitting unit 51 and a first light receiving unit 54 and a second light receiving unit 55 as light receiving units. The first light receiving unit 54 and the second light receiving unit 55 can be hyperspectral sensors, such as a hyperspectral camera. The first light receiving unit 54 and the second light receiving unit 55 receive a continuous spectrum with a spectral range of 300 nm to 2500 nm. According to one embodiment, during the filling of the conductive pillar 20, the light emitting unit 51 emits a monitoring laser Lm from the surface of the substrate 10 to be processed. The monitoring laser Lm reflects off the surface of the substrate 10 to generate a reflected light La signal, and the monitoring laser Lm passes through the surface of the substrate 10 to generate a transmitted light Lb signal. The first light receiving unit 54 receives the reflected light La signal, and the second light receiving unit 55 receives the transmitted light Lb signal. The corresponding spectrum is provided to the image analysis module, which analyzes the spectrum to obtain optical results and transmits the optical results to the processing module (not shown in the figure) to control and adjust the vibration frequency and amplitude of the vibrating disk R based on the optical results. In one embodiment, the monitoring module 50 can be a wavefront monitoring module, which includes a laser device as a light emitting unit 51, a first light receiving unit 54 and a second light receiving unit 55 as light receiving units, and a waveform generator (not shown in the figure). The first light receiving unit 54 and the second light receiving unit 55 can be wavefront sensors and are electrically connected to the waveform generator. The light emitting unit 51 is disposed above the substrate 10 to be processed. According to one embodiment, during the filling of the conductive pillars 20, the light emitting unit 51 emits a laser beam as a monitoring laser Lm onto the surface of the substrate 10 to be processed. The monitoring laser Lm reflects off the surface of the substrate 10 to generate a reflected light La signal, and the monitoring laser Lm passes through the surface of the substrate 10 to generate a transmitted light Lb signal. The first light receiving unit 54 receives the reflected light La signal, and the second light receiving unit 55 receives the transmitted light Lb signal. The received reflected light La signal and transmitted light Lb signal are provided to a waveform generator (not shown in the figure) to analyze the reflected light La signal and transmitted light Lb signal to obtain a waveform detection result, which is then transmitted to the processing module. The processing module can control and adjust the vibration frequency and amplitude of the vibrating disk R based on the waveform detection result. In one embodiment, the monitoring module 50 can be a photoelastic monitoring module, which includes a laser device as a light emitting unit 51, a first light receiving unit 54 and a second light receiving unit 55 as light receiving units, and an imaging device 53. The first light receiving unit 54 and the second light receiving unit 55 can be photoelastic sensors and are electrically connected to the imaging device, and the light emitting unit 51 is disposed above the substrate 10 to be processed. According to one embodiment, during the filling of the conductive pillars 20, the light emitting unit 51 emits a laser beam as a monitoring laser Lm onto the surface of the substrate 10 to be processed. The monitoring laser Lm reflects off the surface of the substrate 10 to generate a reflected light La signal, and the monitoring laser Lm passes through the surface of the substrate 10 to generate a transmitted light Lb signal. The first light receiving unit 54 receives the reflected light La signal, and the second light receiving unit 55 receives the transmitted light Lb signal. The received reflected light La signal and transmitted light Lb signal are provided to the imaging device 53 to analyze the reflected light La signal and transmitted light Lb signal to obtain stress distribution characteristic results. The stress distribution characteristic results are then transmitted to the processing module. The processing module can control and adjust the vibration frequency and amplitude of the vibrating disk R based on the stress distribution characteristic results. In one embodiment, the monitoring module 50 can be a femtosecond ultrasonic monitoring module, comprising a laser device as the light emitting unit 51, a first light receiving unit 54 and a second light receiving unit 55 as the light receiving section, and a waveform generator (not shown in the figure). The light emitting unit 51 is disposed above the substrate 10 to be processed. According to one embodiment, during the filling of the conductive pillar 20, the light emitting unit 51 emits a laser beam as a monitoring laser Lm onto the surface of the substrate 10 to be processed. The monitoring laser Lm reflects off the surface of the substrate 10 to generate a reflected light La signal, and the monitoring laser Lm passes through the surface of the substrate 10 to generate a transmitted light Lb signal. The first light receiving unit 54 receives the reflected light La signal, and the second light receiving unit 55 receives the transmitted light Lb signal. The received reflected light La signal and transmitted light Lb signal are provided to the waveform generator to analyze the reflected light La signal and transmitted light Lb signal to obtain a waveform diagram result, which is then transmitted to the processing module. The processing module can control and adjust the vibration frequency and amplitude of the vibratory plate R based on the waveform results. According to some embodiments, the monitoring module 50 further includes an image detection device 57, which is electrically connected to the image analysis module (image device 53). The image detection device 57 can capture multiple images of the shadowed areas of the substrate 10 that have not been monitored by the laser Lm and transmit them to the image analysis module; the image analysis module receives the multiple images and judges and calculates the defects and probabilities of the shadowed areas based on the multiple images, or compensates for the multiple images and judges and calculates the defects and probabilities of the shadowed areas. For example, the image detection device 57 can be any device capable of capturing images (such as a camera), capturing the shadowed areas in the detection region of the object under test, especially areas where the monitoring laser Lm cannot be received. An image analysis module, such as a computer, can use deep learning to determine the potential defects in the shadowed areas and the probability of those defects occurring, or further determine and calculate the defects and their probability in the shadowed areas by compensating the image. In other words, when the monitoring module 50 of this invention cannot determine the filling status of the conductive post 20 by the monitoring laser Lm, the image detection device 57 can be used to assist in determining the filling status of the conductive post 20, thereby improving the accuracy of defect detection. Furthermore, referring to Figure 6, according to some embodiments, steps S104 and S105 may further include using a cleaning module 60 to remove impurities from the substrate semi-finished product S1. The cleaning module 60 may be disposed above or adjacent to the substrate semi-finished product S1; the present invention does not particularly limit the arrangement of the cleaning module 60. Specifically, the cleaning module 60 may include at least a gas source 61 for storing cleaning material 63, and a gas nozzle 62 for supplying cleaning material 63 to the substrate 10 to be processed or to the substrate 10. For example, the gas source 61 contains liquid carbon dioxide and is supplied to the gas nozzle 62 at a pressure between approximately 700 psi and approximately 900 psi (e.g., any positive integer between 700 psi and 900 psi), causing the liquid carbon dioxide to undergo isenthalpic expansion into a stream of solid carbon dioxide particles as it leaves the gas nozzle 62, thereby carrying away impurities from the substrate 10 to be processed or to the substrate 10. In one embodiment, the distance between the gas nozzle 62 and the substrate 10 to be processed may be between approximately 0.5 inches and approximately 2 inches. In one embodiment, the gas nozzle 62 and the substrate 10 to be processed may have an angle of inclination of approximately 15 degrees to 45 degrees (e.g., any positive integer between 15 and 45 degrees) to prevent the momentum of the carbon dioxide particle stream from being too high and damaging the substrate 10. [Second Embodiment] Please refer to Figure 7, which illustrates the flow steps of a method for forming a substrate with conductive pillars according to a second embodiment of the present invention. As shown in Figure 7, the second embodiment of the present invention has substantially the same implementation as the first embodiment, and the similarities will not be repeated. The difference between the second embodiment and the first embodiment is that, before the drilling process in step S202, the second embodiment further includes a protective treatment of the substrate to be processed (step S201), and after the hole enlargement process in step S203, it further includes removing the protective plate element or protective layer on the surface of the substrate to be processed (step S204). Existing laser processing technologies are prone to producing minor defects such as chipping, burrs, cracks, fissures, and so on when processing substrates (e.g., drilling). To address the problem of delamination or cracking at the drilled holes after substrate processing in existing technologies, the method for forming a substrate with conductive pillars according to the present invention may further include a protective treatment for the substrate to be processed. For details, please refer to Figures 7 and 8. In step S201 of the second embodiment of the present invention, a protective treatment may be performed on the substrate 10 to be processed, which includes temporarily fixing the protective plate element 72 to the upper surface 12 or lower surface 13 of the substrate 10 to be processed using the clamping element 71 of the holding module 70. In this way, the substrate 10 to be processed is protected by the protective plate element 72 during the drilling process in step S202 and the hole enlargement process in step S203, preventing direct impact from the drilling laser L1 and the hole enlargement laser, thereby preventing delamination or cracking at the opening edge of the formed hole 11. Furthermore, Figure 8 shows an example of clamping one substrate 10 to be processed, but the present invention is not limited thereto; in practical applications, two or more substrates 10 to be processed may also be clamped. Furthermore, according to some embodiments, the protective plate element 72 can also be adhered to the surface of the substrate 10 to be processed by the adhesive 73. In addition, referring to Figure 9, in step S201, the protection process may also include providing a protective material to the substrate 10 to be processed, so as to form protective layers A1 and A2 on the upper or lower surface of the substrate to be processed. Specifically, according to some embodiments, the protective treatment may include applying a protective material to the substrate 10 to be processed using a material supply module 81 to form a protective layer on the substrate 10. For example, the substrate 10 to be processed may be placed on a support platform (not shown) to spray the protective material onto the substrate 10, or the substrate 10 may be fixed with a clamp (not shown) before spraying. Furthermore, according to some embodiments, the substrate 10 may be fixed using a single clamp, while according to other embodiments, the substrate 10 may be fixed using a pair of clamps to fix its sides or four sides. Further, according to some embodiments, the protective layer may include a first protective layer A1 and a second protective layer A2. The material supply module 81 may apply a protective material to the upper surface of the substrate 10 to form the first protective layer A1, and apply a protective material to the lower surface of the substrate 10 to form the second protective layer A2. However, according to some embodiments, only one of the first protective layer A1 or the second protective layer A2 may be formed as needed. In addition, according to some embodiments, when the substrate 10 is placed on a support platform, the material supply module 81 applies the protective material to the surface of the substrate 10 in a movable manner to form the first protective layer A1 or the second protective layer A2; and when the substrate 10 is fixed by a clamp, the clamp can flip the substrate 10 to form the first protective layer A1 or the second protective layer A2 on different surfaces of the substrate 10. According to some embodiments, the protective material may be, for example, water, toluene, ethanol, polyvinyl alcohol, hexamethylenedihydrazine, methacrylic acid, methyl methacrylate, n-butyl methyl acrylate, 2-ethylhexyl acrylate, styrene, diethylene glycol ethyl ether acetate, dipropylene glycol methyl ether, or mixtures thereof. Furthermore, according to some embodiments, the viscosity of the protective material may be below 100 cp to form a protective layer with a thickness of 100 nm to 5000 nm (e.g., any positive integer between 100 nm and 5000 nm) on the substrate 10 to be processed. For example, the viscosity of the spraying material may be from 0.01 cp to 100 cp (e.g., any positive integer between 0.01 and 100 cp). In some embodiments, the protective layers A1 and A2 formed of the protective material are liquid at the drilling temperature and gaseous at a predetermined temperature. For example, when the protective material is water, the drilling temperature can be 25°C and the predetermined temperature can be 100°C. In other embodiments, the protective layers A1 and A2 formed of the sprayed material are solid at the drilling temperature and gaseous at the predetermined temperature. However, the examples given above are merely possible embodiments and are not intended to limit the invention. The predetermined temperature can be from 20°C to 500°C (e.g., any positive integer between 20°C and 500°C). Preferably, the predetermined temperature can be from 70°C to 350°C. According to some embodiments, in step S204, the protective plate element 72 or protective layers A1 and A2 on the surface of the substrate 10 to be processed can be removed in a conventional manner. Alternatively, referring to FIG10, the protective layers A1 and A2 formed on the surface of the substrate 10 to be processed can be removed by the material removal module 82. According to some embodiments, the material removal module 82 can be a heating module, which can heat the substrate 10 to be processed to accelerate the removal of protective layers A1 and A2. However, the protective material can also be a volatile substance at a predetermined temperature, so that the protective layer can be removed without using a heating module. For example, in one embodiment of the present invention, the protective material can form a protective layer at a temperature of 10°C. Therefore, after drilling, placing the substrate 10 to be processed at room temperature (10°C) allows the protective layers A1 and A2 to evaporate naturally without the need for heating by a heating module. [Beneficial Effects of the Examples] One of the beneficial effects of the present invention is that the method for forming a substrate with conductive pillars provided by the present invention can increase the aperture of the plurality of holes in the substrate to be processed by using a "hole-expanding laser or an etching process to perform a hole-expanding treatment on a plurality of holes", and reduce the surface roughness of the inner wall of the holes or improve the smoothness of the inner wall of the holes, thereby improving the filling efficiency of the conductive pillars and improving the quality of the substrate with conductive pillars formed. The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made based on the content of the present invention specification and drawings are included in the scope of the patent application of the present invention. M100, M200: Method for forming a substrate with conductive pillars S101~S105: Steps S201~S207: Step 1: Drilling laser device 10: Substrate to be processed 11: Hole 12: Upper surface 13: Lower surface 20: Conductive pillar 30: Adhesive layer 40: Colloid 50: Monitoring module 51: Light emitting unit 52: Control device 53: Imaging device 54: First light receiving unit 55: Second light receiving unit 56: Photography unit 57: Image detection device 60: Cleaning module 61: Gas source 62: Gas nozzle 63: Cleaning substance 70: Holding module 71: Clamping element 72: Protective plate element 73: Adhesive 81: Material supply module 82: Material removal module D1: First aperture D2: Second aperture L1: Drilling laser La: Reflected light Lb: Transmitted light Lm: Monitoring laser S1: Substrate semi-finished product S2: Substrate with conductive pillars Figure 1 is a flowchart of the first embodiment of the present invention. Figure 2 is a cross-sectional schematic diagram of step S101 in Figure 1. Figure 3 is a cross-sectional schematic diagram of a substrate to be processed with a second aperture in one embodiment of the present invention. Figure 4 is a cross-sectional schematic diagram of a monitoring module used in an embodiment of the present invention. Figure 5 is a schematic diagram of the architecture using a monitoring module in one embodiment of the present invention. Figure 6 is a schematic diagram of cleaning using a cleaning module in one embodiment of the present invention. Figure 7 is a flowchart of the second embodiment of the present invention. Figure 8 is a schematic diagram of the protection treatment implementation method in one embodiment of the present invention. Figure 9 is a schematic diagram of the formation of the protective layer in one embodiment of the present invention. Figure 10 is a schematic diagram of the method for removing the protective layer in one embodiment of the present invention. M100: Method for forming a substrate with conductive pillars S101~S105: Steps

Claims

1. A method for forming a substrate having conductive pillars, comprising: A drilling laser is used to drill a substrate to form a plurality of holes on the substrate, wherein the plurality of holes have a first aperture. A plurality of said holes are enlarged using a hole-enlarging laser or an etching process to give the plurality of said holes a second aperture and reduce the surface roughness of the inner walls of the plurality of said holes to 10 nm to 50000 nm, wherein the second aperture is larger than the first aperture; a plurality of conductive pillars are filled into the plurality of said holes having the second aperture; a colloid is filled into the plurality of said holes to fill the gap between the plurality of said conductive pillars and the inner walls of the plurality of said holes to obtain a substrate semi-finished product; and the substrate semi-finished product is ground to obtain a substrate having conductive pillars. The method for forming a substrate having conductive pillars as described in claim 1, wherein, The drilling laser has a wavelength of 300 nm to 2000 nm, a pulse width of 50 fs to 500 fs, and a pulse energy of 10 nJ to 1000 µJ; the via-expansion laser has a wavelength of 300 nm to 2000 nm, a pulse width of 50 fs to 500 fs, and a pulse energy of 10 nJ to 1000 µJ; the etching process includes etching the substrate to be processed with an acidic material or an alkaline material, wherein the acidic material includes hydrogen fluoride, and the alkaline material includes potassium hydroxide; the first aperture is between 1 µm and 10 µm, and the second aperture is between 10 µm and 100 µm. The method for forming a substrate having conductive pillars as described in claim 1, wherein, The substrate to be processed has an upper surface and a lower surface. Before performing the drilling process, the method further includes a protective treatment on the substrate to be processed. The protective treatment includes: using a clamping element to temporarily fix a protective plate element to the upper surface or the lower surface of the substrate to be processed; or providing a protective material to the substrate to be processed to form a protective layer on the upper surface or the lower surface of the substrate to be processed. The method for forming a substrate having conductive pillars as described in claim 1, wherein, The method further includes using a monitoring module to monitor the state of the gaps between the plurality of conductive posts and the inner walls of the plurality of holes, the monitoring module including a camera unit. The method for forming a substrate having conductive pillars as described in claim 1, wherein, The method further includes monitoring the substrate to be processed using a monitoring module, the monitoring module comprising: an optical module including a light emitting unit and a light receiving unit, the light emitting unit emitting a monitoring laser toward the substrate to be processed, wherein the wavelength range of the monitoring laser is 300 nm to 2000 nm and the pulse width range of the monitoring laser is 50 fs to 50 ns; and an image analysis module electrically connected to the optical module. The method for forming a substrate having conductive pillars as described in claim 5, wherein, The light receiving unit includes a first wavefront sensor and a second wavefront sensor. The first wavefront sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second wavefront sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. The image analysis module includes a waveform generator electrically connected to the first wavefront sensor and the second wavefront sensor. The waveform generator is used to receive the reflected light signal and the transmitted light signal, and generate a first detection waveform corresponding to the reflected light signal and a second detection waveform corresponding to the transmitted light signal. The method for forming a substrate having conductive pillars as described in claim 5, wherein, The light receiving unit includes a first photoelastic sensor and a second photoelastic sensor. The first photoelastic sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second photoelastic sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. The image analysis module includes an image device electrically connected to the first photoelastic sensor and the second photoelastic sensor. The image device is used to receive the reflected light signal and the transmitted light signal, and generate a first stress distribution feature map corresponding to the reflected light signal and a second stress distribution feature map corresponding to the transmitted light signal. The method for forming a substrate having conductive pillars as described in claim 5, wherein, The optical receiving unit includes a first laser vibrometer and a second laser vibrometer. The first laser vibrometer is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected ultrasound wave. The second laser vibrometer is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted ultrasound wave. The image analysis module includes a waveform generator electrically connected to the first laser vibrometer and the second laser vibrometer. The waveform generator is used to receive the reflected ultrasound wave and the transmitted ultrasound wave and generate a first waveform corresponding to the reflected ultrasound wave and a second waveform corresponding to the transmitted ultrasound wave. The method for forming a substrate having conductive pillars as described in claim 5, wherein, The light receiving unit includes a first hyperspectral sensor and a second hyperspectral sensor. The first hyperspectral sensor is disposed on a first side of the substrate to be processed and is used to receive reflected light from the monitoring laser reflected by the substrate to generate a reflected light signal. The second hyperspectral sensor is disposed on a second side of the substrate to be processed and is used to receive transmitted light from the monitoring laser passing through the substrate to generate a transmitted light signal. The first and second hyperspectral sensors receive a spectral range of 300 nm to 2500 nm, and the spectrum is a continuous spectrum. The image analysis module includes a hyperspectral generator electrically connected to the first and second hyperspectral sensors. The hyperspectral generator is used to receive the reflected light signal and the transmitted light signal, and generate a first detection spectrum corresponding to the reflected light signal and a second detection spectrum corresponding to the transmitted light signal. The method for forming a substrate having conductive pillars as described in claim 5, wherein, The monitoring module further includes an image detection device electrically connected to the image analysis module. The image detection device is configured to detect and capture multiple images of a shadow area of ​​the substrate to be processed that has not been exposed to the monitoring laser. The image analysis module receives the multiple images and, based on the multiple images, determines and calculates the defects and probabilities of the shadow area, or compensates for the multiple images and determines and calculates the defects and probabilities of the shadow area.

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