Preparation method and preparation device of glass through hole

Abstract

The invention provides a preparation method and a preparation device of a glass through hole, and relates to the technical field of glass preparation. The preparation method comprises the following steps: S1, providing a glass substrate, and carrying out surface pretreatment on the glass substrate; s2, performing prefabricated punching on the target area of the glass substrate by adopting pulse laser so as to form a prefabricated hole in the target area; s3, performing etching and magnetic grinding on the prefabricated hole of the glass substrate; s4, carrying out surface post-treatment on the glass substrate to prepare the glass substrate with a through hole; wherein etching and magnetic grinding are carried out on the prefabricated hole in the step S3, specifically, the glass substrate is soaked in etching liquid for etching, polishing and grinding are carried out on the prefabricated hole through reciprocating motion of magnetic powder in a magnetic field, and the etching liquid is a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride and nitric acid.

Description

Technical Field

[0001] The present disclosure relates to the technical field of glass preparation, and particularly to a method and a device for preparing glass through holes. Background Art

[0002] With the rapid rise of advanced technologies such as the Internet of Things and AI, the requirements for the packaging technology of interposer boards are getting higher and higher. Currently, silicon-based interposer boards are often used. However, for the through-hole technology TSV of silicon substrates, an oxide insulating layer is required after the through holes are formed. This is mainly because silicon is a semiconductor material that can generate a certain electromagnetic coupling effect, and eddy current phenomena occur in the substrate, which will cause certain interference to the signal transmission. As an alternative to silicon-based interposer boards, glass interposer boards have a low cost. Since they are insulators, glass interposer boards do not have obvious electromagnetic coupling effects and have excellent high-frequency electrical characteristics, and are attracting more and more attention. Common glass substrate materials include silicate glass, quartz glass, and borosilicate glass. Ultra-thin glass (usually with a thickness of less than 0.1 mm) has a higher transmittance. A wafer based on ultra-thin glass can integrate more circuits in a smaller space, can reduce the power consumption of the chip, and the energy utilization efficiency of data will be higher.

[0003] The glass through-hole technology (TGV) is the key to semiconductor packaging of glass substrates. Common preparation methods include sandblasting method, photosensitive glass method, focused discharge method, plasma etching method, laser ablation method, laser-induced etching method, etc. Among them, the commonly used one is the laser-induced etching method. However, for the through holes of ultra-thin glass, during the induced etching process, problems such as cracking of the generated through-hole edges and large roughness of the through-hole inner walls often occur. Summary of the Invention

[0004] One technical problem to be solved by the present disclosure is that during the process of processing the through holes of ultra-thin glass again by the laser-induced etching method, problems such as cracking of the generated through-hole edges and large roughness of the through-hole inner walls exist.

[0005] To solve the above technical problem, an embodiment of the present disclosure provides a method for preparing glass through holes. The method for preparing glass through holes includes:

[0006] S1. Provide a glass substrate and perform surface pretreatment on the glass substrate;

[0007] S2. Use pulsed laser to pre-drill a target area of the glass substrate to form a pre-drilled hole in the target area;

[0008] S3. Etch and magnetically polish the pre-drilled hole of the glass substrate;

[0009] S4. Perform surface post-treatment on the glass substrate to obtain a glass substrate with through holes;

[0010] Among them, in step S3, etching and magnetic abrasive finishing are performed on the prefabricated holes, specifically as follows:

[0011] The glass substrate is immersed in the etching solution for etching, and the prefabricated holes are polished by the reciprocating movement of magnetic powder in the magnetic field. The etching solution is a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride, and nitric acid.

[0012] In some embodiments, the mass ratio of the components of the ternary mixed acid system is hydrogen fluoride: hydrogen chloride: nitric acid: water = (8 - 20):(1 - 3):(1 - 3):100.

[0013] In some embodiments, the surface pretreatment in step S1 includes: masking the glass substrate.

[0014] In some embodiments, the surface post-treatment in step S4 includes at least: removing the mask, and cleaning and drying the glass substrate.

[0015] In some embodiments, the magnetic powder includes: a main body and a coating layer wrapped around the outside of the main body. The main body is formed of at least one of iron, cobalt, and nickel, and the coating layer is formed of a polymer material inert to acid.

[0016] In some embodiments, the temperature of the etching solution is 30 - 60 °C, and the etching time is 80 - 120 min.

[0017] In some embodiments, the pulse width of the pulsed laser beam in step S2 is between 3 - 15 ps, the repetition frequency is between 20 - 50 kHz, and the pulse energy is between 10 - 50 μJ.

[0018] The embodiments of the present disclosure further provide a device for preparing glass through-holes. The device for preparing glass through-holes includes: a processing tank, the inside of which includes a first cavity with an open top side. The first cavity is used to accommodate the etching solution and magnetic powder and place the glass substrate;

[0019] At least two magnetic field generator components are respectively arranged on two opposite sides of the processing tank in the first direction and corresponding to the first cavity, and are at least used to control the direction of the magnetic field so that the magnetic powder generates a reciprocating movement;

[0020] Among them, the first direction is perpendicular to the depth direction of the processing tank.

[0021] In some embodiments, the inside of the processing tank further includes a second cavity separated from the first cavity, and the first cavity is located on top of the second cavity;

[0022] The device for preparing glass through-holes further includes:

[0023] An ultrasonic generator is arranged in the second cavity and is used to generate ultrasonic waves to disperse the magnetic powder.

[0024] In some embodiments, a plurality of slots are respectively arranged along a first direction on the inner sides of two opposite sides of the first cavity in a second direction, and two opposite slots in the second direction are respectively used for plugging the two side edges of the glass substrate.

[0025] Through the above technical solution, the method and device for preparing a glass through hole provided by the present disclosure adopt a mask to coat the glass substrate. When preparing a prefabricated hole by laser induction, quality problems such as fission caused by excessive laser irradiation on the edge of the prefabricated hole can be avoided, making the prefabricated hole more regular; in the etching stage after laser induction, a ternary mixed acid system is used as the etching solution. On the premise of ensuring a necessary etching speed, the roughness of the inner wall of the prefabricated hole can be avoided from being too large, increasing the difficulty of subsequent grinding and polishing. By adding a controllable magnetic field and using the reciprocating motion of magnetic powder in the magnetic field to grind and polish the inner wall of the prefabricated hole, the roughness of the inner wall of the prefabricated hole can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 is a schematic flowchart of the method for preparing a glass through hole disclosed in the embodiment of the present disclosure;

[0028] Figure 2 is a top view structural schematic diagram of the device for preparing a glass through hole disclosed in the embodiment of the present disclosure;

[0029] Figure 3 is a cross-sectional structural schematic diagram of the device for preparing a glass through hole disclosed in the embodiment of the present disclosure.

[0030] Description of the reference numerals:

[0031] 1. Processing tank; 101. First cavity; 1011. Slot; 102. Second cavity; 2. Magnetic field generator assembly; 3. Ultrasonic generator; 4. Glass substrate; a. First direction; b. Second direction. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following will further describe in detail the embodiments of the present disclosure in conjunction with the drawings and embodiments. The detailed description and drawings of the following embodiments are used to exemplarily illustrate the principle of the present disclosure, but cannot be used to limit the scope of the present disclosure. The present disclosure can be implemented in many different forms, not limited to the specific embodiments disclosed in the text, but including all technical solutions falling within the scope of the claims.

[0033] The present disclosure provides these embodiments to make the present disclosure thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, the compositions of materials, numerical expressions and values set forth in these embodiments should be construed as merely exemplary and not as limitations.

[0034] It should be noted that in the description of the present disclosure, unless otherwise specified, the meaning of "a plurality" is greater than or equal to two; the orientation or positional relationships indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present disclosure. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0035] In addition, the "first", "second" and similar terms used in the present disclosure do not denote any order, quantity or importance, but are only used to distinguish different parts. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range. Words such as "including" or "comprising" mean that the elements before this word cover the elements listed after this word, and do not exclude the possibility of also covering other elements.

[0036] It should also be noted that in the description of the present disclosure, unless otherwise clearly specified and limited, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances. When it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0037] All terms used in the present disclosure have the same meanings as those understood by those of ordinary skill in the art to which the present disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as those, should be construed to have meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such here.

[0038] Technologies, methods and devices known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the specification.

[0039] Example 1

[0040] Reference appendix Figure 1 , Example 1 of the present invention proposes a method for preparing glass through-holes, and the preparation method includes:

[0041] S1. Provide a glass substrate 4;

[0042] Specifically, in this embodiment, a laser-induced etching method is used to process through-holes in the glass substrate 4. The thickness of the glass substrate 4 can be, but is not limited to, an ultra-thin glass of 0.5 mm. Before laser induction, surface pretreatment is performed on the glass substrate 4. Here, the surface pretreatment may include: ultrasonically cleaning the glass substrate 4 to remove dust and organic impurities on the surface of the glass substrate 4, which can be washed with pure water and anhydrous ethanol respectively, and then with pure water for three times, and dried for later use; the surface pretreatment may also include: masking the glass substrate 4. The specific operation process is: covering the cleaned and dried glass substrate 4 with a mask. During this process, it is ensured that the mask is tightly attached to the surface of the glass substrate 4, and no air enters the attachment surface, and it does not react with acid. The thickness of the mask can be 30-60 μm. For example, the mask can be a polyimide film CPI with a thickness of about 45 μm. Of course, other films that meet the performance requirements can also be applicable; covering the glass substrate 4 with a mask during the surface pretreatment process can avoid quality problems such as cracked edges caused by excessive laser irradiation on the edges of the prefabricated holes during subsequent laser-induced preparation of the prefabricated holes, and can make the prepared prefabricated holes more regular. Moreover, during the etching process, the mask can also block the erosion of the mixed acid on the through-hole edges and the periphery, which has significant benefits in protecting the non-etched area, improving the etching accuracy, reducing defects and damages, and improving the production efficiency and the yield rate, etc.

[0043] S2. Use pulsed laser to perform prefabricated punching on the target area of the glass substrate 4 to form a prefabricated hole in the target area;

[0044] Specifically, in this step, pulsed laser is used to perform prefabricated punching on the target area of the glass substrate 4 after surface pretreatment. The pulse width of the pulsed laser beam is between 3-15 ps, the repetition frequency is between 20-50 kHz, and the pulse energy is between 10-50 μJ, which can achieve high-precision and high-quality punching. The formed prefabricated hole has high dimensional accuracy and small deviation, the inner wall of the prefabricated hole is smooth and regular, and at the same time, the heat-affected zone is small and can be almost ignored, thus effectively avoiding thermal damage to the surrounding area of the glass substrate 4 and ensuring that the overall performance and strength of the material are not affected.

[0045] S3. Perform surface pretreatment on the glass substrate 4, and etch and magnetically polish the prefabricated holes of the glass substrate 4 after surface pretreatment; wherein, the etching and magnetic polishing of the prefabricated holes are specifically as follows: Immerse the glass substrate 4 in the etching solution for etching, and polish and grind the prefabricated holes through the reciprocating movement of the magnetic powder in the magnetic field. The etching solution is a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride, and nitric acid;

[0046] Specifically, after forming the prefabricated holes, in order to reduce the roughness of the inner wall of the prefabricated holes, the prefabricated holes are subjected to etching and magnetic polishing treatment. During the etching process, the glass substrate is immersed in the etching solution. The etching solution is a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride, and nitric acid. The temperature can be 30 - 60 °C, the rotation speed of the etching machine can be 3 r / min, and the etching time is 80 - 120 min. Among them, the hydrogen fluoride in the ternary mixed acid system etching solution used can react with the silicon in the glass to destroy the chemical structure of the glass to achieve the effect of corrosion etching. However, insoluble inorganic substances will accumulate at the corrosion interface after etching, hindering the further contact between hydrogen fluoride and the glass and reducing the etching speed. The hydrogen chloride and nitric acid in the ternary mixed acid system etching solution can react with the insoluble inorganic substances at the etching interface to form soluble substances, thereby removing the inorganic residues accumulated at the reaction interface and enabling the etching reaction to continue; Since nitric acid has strong oxidizing properties, it can, to a certain extent, destroy the crystal lattice structure of the glass and promote the etching reaction. In addition, the use of the ternary mixed acid system can also indirectly reduce the hydrogen fluoride concentration at the local reaction interface, avoiding excessive roughness of the inner wall of the prefabricated holes due to overly intense reaction during etching; Among them, the mass ratio of the components of the ternary mixed acid system is hydrogen fluoride: hydrogen chloride: nitric acid: water = 8 - 20: 1 - 3: 1 - 3: 100. By setting a specific mass ratio, the etching efficiency and quality can be significantly improved, the etching stability can be enhanced, and the cost - benefit can be optimized.

[0047] In addition, during the etching stage after laser induction, a controllable magnetic field is added. By utilizing the reciprocating motion of magnetic powder in the magnetic field, the inner wall of the prefabricated hole is ground and polished, reducing the roughness of the inner wall of the through-hole. The magnetic powder can be in the same treatment tank 1 as the etching solution and reciprocate under the control of the magnetic field. The specific implementation method will be described in detail below. The magnetic powder includes: a main body and a coating layer wrapped around the outside of the main body. The main body is formed of at least one of iron, cobalt, and nickel. For example, the main body can be a pure substance of iron, cobalt, or nickel, or an alloy material formed by at least two of them. The coating layer is formed of a polymer material inert to acid. The thickness of the coating layer can be 10%-30% of the diameter of the main body. This polymer material can be epoxy resin, polyamide resin, silicone resin, polyvinyl alcohol, phenolic resin, polystyrene, etc., or can also be other organic materials that are easy to coat and do not react with acid. The particle size of the magnetic powder includes the coating layer gradation: the proportion of 6-8μm is 10%-20%, the proportion of 2-4μm is 40%-60%, and the rest is 1μm and below.

[0048] S4. Perform surface post-treatment on the glass substrate 4 to obtain a glass substrate 4 with through-holes.

[0049] Specifically, after the etching and grinding treatment of the prefabricated hole is completed, surface post-treatment can be performed on the glass substrate 4 to obtain a glass substrate 4 with through-holes. Among them, the surface post-treatment can include: removing the mask, and cleaning and drying the glass substrate 4. Here, the cleaning can be ultrasonic cleaning using ethanol and pure water.

[0050] According to the above, the embodiment of the present invention provides a method for preparing glass through-holes. By using a mask to coat the glass substrate 4, when preparing prefabricated holes by laser induction, quality problems such as fission caused by excessive laser irradiation at the edge of the prefabricated holes can be avoided, making the prefabricated holes more regular. During the etching stage after laser induction, a ternary mixed acid system is used as the etching solution. On the premise of ensuring the necessary etching speed, the roughness of the inner wall of the prefabricated hole can be avoided from being too large, increasing the difficulty of subsequent grinding and polishing. By adding a controllable magnetic field and utilizing the reciprocating motion of magnetic powder in the magnetic field, the inner wall of the prefabricated hole is ground and polished, and the roughness of the inner wall of the prefabricated hole can be reduced.

[0051] Embodiment 2

[0052] Refer to the appendix Figure 2 and the appendix Figure 3, Embodiment 2 of the present invention provides a preparation device for glass through-holes, which is applied to the above-mentioned method for preparing glass through-holes. The preparation device includes: a processing tank 1, the inside of which includes a first cavity 101 with an open top side. The first cavity 101 is used to accommodate the etching solution and magnetic powder and place the glass substrate 4; at least two magnetic field generator components 2 are respectively arranged on two opposite sides of the processing tank 1 in the first direction a and corresponding to the first cavity 101, and are at least used to control the direction of the magnetic field so that the magnetic powder generates reciprocating motion; wherein, the first direction a is perpendicular to the depth direction of the processing tank 1.

[0053] Specifically, the preparation device for glass through-holes provided in this embodiment is applied to step S3 in the above-mentioned method for preparing glass through-holes, and is used for etching and magnetic abrasive polishing of the prefabricated holes. The main structure of the preparation device is the processing tank 1. The inside of the processing tank 1 includes a first cavity 101 with an open top side. The cross-sectional shape of the first cavity 101 can be rectangular, its length direction can be the first direction a, and its width direction can be the second direction b. The first cavity 101 contains the etching solution and magnetic powder, and can be used to place the glass substrate 4. The number of glass substrates 4 that can be placed in the first cavity 101 is not limited to one, that is, synchronous etching and grinding treatment of multiple glass substrates 4 can be realized through the preparation device; the etching solution can be a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride and nitric acid, and the ratio can be hydrogen fluoride: hydrogen chloride: nitric acid: water = 8 - 20: 1 - 3: 1 - 3: 100. All parts in the first cavity 101 that come into contact with the etching solution do not react with the etching solution; magnetic field generator components 2 are respectively arranged on two opposite sides of the processing tank 1 in the first direction a. The magnetic field generator component 2 can include: an AC power supply module, a controller and a coil. By continuously changing the direction of the alternating current, the direction of the magnetic field can be changed. By changing the magnitude of the current, the intensity of the magnetic field can be controlled, so as to realize the control of the magnetic powder. Among them, the frequency of the magnetic field direction change can be 400 - 600 times / min, and the magnitude of the applied alternating current can be 50 - 80 A. For example, the frequency of the magnetic field change can be set to 500 times / min, and the applied alternating current is 60 A; in the initial stage of etching, the reciprocating motion of the magnetic powder will accelerate the etching process of the prefabricated holes, and after the etching is completed, the reciprocating motion of the magnetic powder will play a role in polishing and grinding the inner wall of the prefabricated holes.

[0054] Refer to the attached Figure 1 and the attached Figure 2, in a specific implementation, in order to disperse the magnetic powder, in the technical solution adopted by the present invention, the inside of the treatment tank 1 further includes a second cavity 102 separated from the first cavity 101. The first cavity 101 is located at the top of the second cavity 102. The second cavity 102 is not in contact with the etching solution, and an ultrasonic generator 3 is arranged inside it. The ultrasonic generator 3 can be arranged in the center of the second cavity 102; the ultrasonic generator 3 can generate a certain amount of ultrasonic waves to play a role in dispersing the magnetic powder. The vibration frequency of the ultrasonic generator 3 can be between 50 kHz and 70 kHz. For example, the vibration frequency of the ultrasonic generator 3 can be set to 60 kHz.

[0055] Reference appendix Figure 1 , in a specific implementation, in order to improve the stability of the glass substrate 4 fixed in the first cavity 101, in the technical solution adopted by the present invention, a plurality of slots 1011 are respectively arranged along the first direction a on the inner sides of the two opposite sides of the first cavity 101 in the second direction b, so as to realize the placement of a plurality of glass substrates 4. The two slots 1011 opposite to each other in the second direction b are a group, and are respectively used to insert the two side edges of the glass substrate 4. There is a certain interval between each group of slots 1011, and the interval distance can be set according to the actual situation.

[0056] So far, the embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details well known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed here based on the above description.

[0057] Although some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present disclosure. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way.

Claims

1. A method for preparing a through-glass via, characterized in that: include: S1, providing a glass substrate (4), and performing surface pretreatment on the glass substrate (4); S2, using a pulsed laser to perform pre-drilling on a target area of ​​the glass substrate (4) to form a pre-drilled hole in the target area; S3, etching and magnetically grinding the prefabricated holes of the glass substrate (4); S4, performing surface post-treatment on the glass substrate (4) to obtain the glass substrate (4) having through holes; Wherein, the etching and magnetic grinding of the prefabricated hole in step S3 are specifically as follows: The glass substrate (4) is immersed in an etching solution for etching, and the prefabricated holes are polished and ground by reciprocating motion of magnetic powder in a magnetic field. The etching solution is a ternary mixed acid system formed by mixing hydrogen fluoride, hydrogen chloride and nitric acid.

2. The method for preparing a through-glass via according to claim 1, characterized in that: The components of the ternary mixed acid system are in a ratio of hydrogen fluoride: hydrogen chloride: nitric acid: water = (8-20): (1-3): (1-3): 100 by mass.

3. The method for preparing a through-glass via according to claim 1, characterized in that: The surface pre-treatment in the step S1 comprises: masking the glass substrate (4).

4. The method for preparing a through-glass via according to claim 3, characterized in that: The surface post-treatment in step S4 at least includes: removing the mask, and cleaning and drying the glass substrate (4).

5. The method for preparing a through-glass via according to claim 1, characterized in that: The magnetic powder comprises: a main body and a coating layer wrapped around the main body, the main body is formed of at least one substance selected from iron, cobalt and nickel, and the coating layer is formed of a polymer material inert to acid.

6. The method for preparing a through-glass via according to claim 1, characterized in that: The temperature of the etching solution is 30-60° C., and the etching time is 80-120 min.

7. The method for preparing a through-glass via according to claim 1, characterized in that: The pulse width of the pulse laser beam in step S2 is between 3-15 ps, the repetition frequency is between 20-50 kHz, and the pulse energy is between 10-50 μJ.

8. A through-glass via manufacturing device, applied to the through-glass via manufacturing method as claimed in any one of claims 1 to 7, characterized in that: include: A processing tank, the interior of which comprises a first cavity (101) with an opening on the top side, wherein the first cavity (101) is used to contain etching liquid and magnetic powder and to place a glass substrate (4); At least two magnetic field generator assemblies (2) are disposed on opposite sides of the processing tank in the first direction (a) and correspond to the first cavity (101), and are used at least to control the direction of the magnetic field so as to cause the magnetic powder to generate reciprocating motion; Wherein, the first direction (a) is perpendicular to the depth direction of the processing tank.

9. The through-glass via manufacturing device according to claim 8, characterized in that: The interior of the treatment tank further includes a second cavity (102) separated from the first cavity (101), and the first cavity (101) is located on the top of the second cavity (102); The through-glass via preparation device further comprises: An ultrasonic generator (3) is arranged in the second cavity (102) and is used to generate ultrasonic waves to disperse the magnetic powder.

10. The through-glass via manufacturing device according to claim 9, characterized in that: The first cavity (101) is provided with a plurality of slots (1011) along the first direction (a) on two opposite sides thereof in the second direction (b), and the two opposite slots (1011) in the second direction (b) are used to insert two side edges of the glass substrate (4) respectively.

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