Method for manufacturing a glass substrate

Abstract

The application provides a glass substrate preparation method, comprising the following steps: preparing a glass core layer, which is divided into multiple substrate units by a cutting path; forming multiple stacked units stacked along a direction perpendicular to the glass core layer above the substrate units, the stacked units comprising multiple re-wiring units stacked along a direction perpendicular to the glass core layer, and between the stacked units above adjacent substrate units being all or partial cutting-off areas when forming each layer of the stacked units; cutting the remaining area between the glass core layer and the stacked units along the cutting path to form independent glass substrates. The preparation method can avoid glass substrate fragmentation, reduce the glass substrate fragmentation rate, and improve the cutting yield of the glass substrate.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit packaging, and more particularly to a method for preparing a glass substrate. Background Technology

[0002] As a new type of substrate, glass substrates are gradually replacing resin substrates due to their excellent thermal stability, fast signal transmission speed, low loss, and high strength, and are very likely to become the mainstream substrate material in the future.

[0003] like Figure 1 The diagram shows a conventional glass substrate, which includes a glass core layer 100 and a resin layer 200 covering the upper and lower surfaces of the glass core layer 100. The resin layer 200, such as an ABF layer (Ajinomoto Build-up Film), is a key functional insulating layer in glass substrate encapsulation. Through-holes are formed in the resin layer 200 using laser drilling, followed by chemical copper plating and electroplating to fill the holes, thus constructing a vertical interconnect structure. The vertical interconnect structure located on the upper surface of the glass core layer 100 and the vertical interconnect structure located on the lower surface of the glass chip are electrically connected through through-glass vias (TGVs) 101 that penetrate the glass core layer 100.

[0004] In the field of glass substrate processing, the mainstream technologies for cutting large-size substrates (panels) into single chips can be divided into the following two categories: The first approach: composite tool cutting process. First, a metal tool is used to cut the resin layer 200 on the upper and lower surfaces of the glass core layer 100; then, a resin tool is used to cut the glass core layer 100. This technical solution has the following drawbacks: Figure 2 The diagram shows a conventional method of cutting the resin layer 200 on the upper and lower surfaces of the glass core layer 100 with a metal blade. The resin layer 200 is formed by multiple layers of sub-layers 201 through repeated pressing and baking. Residual stress accumulates within it. When the resin layer 200 is cut with a metal blade, this stress is released instantaneously, causing microcracks at the interface between the resin layer 200 and the glass core layer 100, resulting in delamination. Furthermore, due to the mismatch in thermal expansion coefficients between the resin layer 200 and the glass core layer 100, the delamination area extends to the edge of the through-glass via (TGV) under the cutting stress. Figure 3The diagram illustrates the result of cutting the glass core layer 100 using a resin cutter. Due to the delamination between the resin layer 200 and the glass core layer 100, the cutting pressure is concentrated in the glass via area during the cutting process. This delamination weakens the glass's mechanical strength, causing cracks to propagate along the via walls into the glass core layer 100, forming a radial crack network and ultimately rendering the glass substrate unusable. Furthermore, in this cutting process, the glass substrate fragmentation rate increases significantly with the increase in the number of resin layer 200 stacks. The second approach: laser-mechanical composite cutting process. First, the resin layer 200 is ablated using a laser, then the glass core layer 100 is cut using a resin blade. This technical solution has the following drawbacks: Figure 4 As shown, this is a schematic diagram of the existing laser ablation of resin layer 200. During laser ablation of resin layer 200, the pulse energy density easily induces resin carbonization, forming a stepped microporous structure. The size of the stepped microporous structure is larger than the size of the resin ablation blade. Figure 5 The diagram shows a conventional method of cutting the glass core layer 100 using a resin cutter. The glass core layer 100 is cut using a resin cutter at the stepped microporous structure 202. Because the size of the stepped microporous structure 202 is larger than the size of the resin cutter, some glass will be exposed at the glass edge after cutting the glass core layer 100. To avoid damage to the edge of the glass core layer 100, the exposed area needs to be protected with a protective adhesive, such as... Figure 6 The diagram shows an existing method using protective adhesive 300 to protect the edge of the glass core layer 100. The Young's modulus of the protective adhesive 300 does not match the Young's modulus of the glass, resulting in the glass core layer 100 still cracking at high temperatures.

[0005] Therefore, how to prepare glass substrates that meet the requirements, reduce the breakage rate of glass substrates, and improve the cutting yield of glass substrates have become urgent technical problems to be solved. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing a glass substrate, which can avoid glass substrate breakage, reduce the glass substrate fragmentation rate, and improve the glass substrate cutting yield.

[0007] To address the aforementioned problems, the present invention provides a method for preparing a glass substrate, comprising the following steps: fabricating a glass core layer, wherein the glass core layer is divided into multiple substrate units by a dicing channel; forming a multilayer stacked unit above the substrate units, the stacked unit including a multilayer redistribution unit stacked in a direction perpendicular to the glass core layer; wherein, when forming each layer of the stacked unit, the stacked units above adjacent substrate units are completely or partially cut off; and cutting the remaining area between the glass core layer and the stacked units along the dicing channel to form an independent glass substrate.

[0008] In one specific embodiment, the method for fabricating the glass core layer further includes the following steps: providing a glass plate; forming a glass through-hole penetrating the glass plate, an upper conductive layer located on the upper surface of the glass plate, and a lower conductive layer located on the lower surface of the glass plate, wherein the upper conductive layer is electrically connected to the lower conductive layer through the glass through-hole; and in the step of forming a multilayer stacked unit stacked in a direction perpendicular to the glass core layer above the substrate unit, wherein the stacked unit is formed on the upper conductive layer and / or the lower conductive layer.

[0009] In one specific embodiment, the step of forming a glass through-hole, an upper conductive layer on the upper surface of the glass plate, and a lower conductive layer on the lower surface of the glass plate further includes: forming a through-hole; forming a metal layer in the through-hole, on the upper surface and the lower surface of the glass plate; patterning the metal layer on the upper surface and the lower surface of the glass plate to form the upper conductive layer and the lower conductive layer, wherein the metal layer in the through-hole serves as the glass through-hole, and the glass through-hole is electrically connected to the upper conductive layer and the lower conductive layer.

[0010] In one specific embodiment, the step of forming a through-hole through the glass plate further includes: modifying the area of ​​the glass plate where the through-hole needs to be formed; etching the modified area to form the through-hole.

[0011] In one specific embodiment, the step of modifying the area of ​​the glass plate where the via needs to be formed further includes: using laser modification on the area of ​​the glass plate where the via needs to be formed.

[0012] In one specific embodiment, the step of etching the modified area further includes immersing the modified glass plate in an etching solution to etch the modified area.

[0013] In one specific embodiment, the step of forming a metal layer in the via, on the upper and lower surfaces of the glass plate, further includes: forming a seed layer in the via, on the upper and lower surfaces of the glass plate; performing an electroplating process to form the metal layer on the seed layer; and simultaneously patterning the seed layer in the step of patterning the metal layer on the upper and lower surfaces of the glass plate.

[0014] In one specific embodiment, the step of performing an electroplating process to form the metal layer on the seed layer further includes performing a baking process after electroplating.

[0015] In one specific embodiment, prior to the step of forming a seed layer in the via, on the upper and lower surfaces of the glass plate, the method further includes: performing interface optimization treatment on the upper and lower surfaces of the glass plate.

[0016] In one specific embodiment, the step of patterning the metal layers on the upper and lower surfaces of the glass plate further includes: forming a patterned mask layer on the surface of the metal layer, the mask layer having an opening that exposes the area of ​​the metal layer to be removed; removing the metal layer along the opening, the remaining metal layer serving as the upper conductive layer and the lower conductive layer; and removing the mask layer.

[0017] In one specific embodiment, the step of patterning the metal layer on the upper and lower surfaces of the glass plate further includes: thinning the metal layer.

[0018] In one specific embodiment, after the step of patterning the metal layers on the upper and lower surfaces of the glass plate, the method further includes: forming an upper dielectric layer on the upper surface of the glass plate, forming a lower dielectric layer on the lower surface of the glass plate, wherein the upper dielectric layer fills the gaps in the upper conductive layer, and the lower dielectric layer fills the gaps in the lower conductive layer.

[0019] In one specific embodiment, the step of forming an upper dielectric layer on the upper surface of the glass plate and a lower dielectric layer on the lower surface of the glass plate further includes: forming a dielectric material layer, the dielectric material layer covering the upper surface of the glass plate and the upper conductive layer, the lower surface of the glass plate and the lower conductive layer; thinning the dielectric material layer, using the upper conductive layer and the lower conductive layer as stop layers, to form the upper dielectric layer and the lower dielectric layer.

[0020] In one specific embodiment, the step of forming a glass through-hole, an upper conductive layer on the upper surface of the glass plate, and a lower conductive layer on the lower surface of the glass plate further includes: forming a through-hole; forming a seed layer in the through-hole, on the upper surface and lower surface of the glass plate; patterning the seed layer, retaining the areas where the upper and lower conductive layers need to be formed, and the seed layer in the through-hole; performing an electroplating process to form the glass through-hole, the upper conductive layer, and the lower conductive layer on the seed layer, wherein the glass through-hole is electrically connected to the upper conductive layer and the lower conductive layer.

[0021] In one specific embodiment, the step of forming each of the stacked units further includes: forming a multilayer redistribution layer stacked in a direction perpendicular to the glass core layer above the substrate unit; dividing the redistribution layer along a cutting trajectory, such that the stacked units above adjacent substrate units are all or partially cut off, the cutting trajectory being the same as the trajectory of the cutting channel.

[0022] In one specific embodiment, the method of forming each redistribution layer in the step of forming a multilayer redistribution layer stacked in a direction perpendicular to the glass core layer above the substrate unit includes: forming an insulating layer above the substrate unit; forming a conductive connection structure in the insulating layer and forming a conductive line layer on the insulating layer, the conductive line layer being electrically connected to the conductive connection structure; the step of dividing the redistribution layer along a cutting trajectory further includes: dividing the insulating layer and the conductive line layer along a cutting trajectory to form insulating units and conductive line units, such that the insulating units above adjacent substrate units and the conductive line units are all or partially cut off.

[0023] In one specific embodiment, the step of forming an insulating layer over the substrate unit further includes providing a single sheet of insulating material; and pressing the insulating material layer onto the glass core layer as the insulating layer.

[0024] In one specific embodiment, the method of pressing the insulating material layer onto the glass core layer is hot pressing.

[0025] In one specific embodiment, the steps of forming a conductive connection structure in the insulating layer and forming a conductive circuit layer on the insulating layer further include: forming a via in the insulating layer; forming a conductive material layer on the insulating layer, the conductive material layer further filling the via; patterning the conductive material layer to form the conductive circuit layer, wherein the conductive material layer within the via serves as the conductive connection structure.

[0026] In one specific embodiment, prior to the step of forming a conductive material layer on the insulating layer, the method further includes: forming a seed layer on the insulating layer, the seed layer also covering the inner wall of the via; the step of forming a conductive material layer on the insulating layer further includes: performing an electroplating process to form the conductive material layer on the seed layer.

[0027] In one specific embodiment, the insulating layer is an organic resin film layer.

[0028] In one specific embodiment, the step of dividing the redistribution layer along a cutting trajectory further includes: dividing part or all of the redistribution layer along the cutting trajectory using laser cutting or mechanical cutting processes.

[0029] In one specific embodiment, a method for dividing the redistribution layer along a cutting trajectory to create a completely cut-off area between the stacked units above adjacent substrate units includes: dividing all the redistribution layers along the cutting trajectory until the redistribution layers are completely disconnected.

[0030] In one specific embodiment, a method for dividing the redistribution layers along a cutting trajectory to create a partially cut-off region between the stacked units above adjacent substrate units includes: dividing all the redistribution layers along the cutting trajectory to a predetermined depth, so that all the redistribution layers are partially disconnected. In one embodiment, a method for dividing the redistribution layers along a cutting trajectory to create a partially cut-off region between the stacked units above adjacent substrate units includes: intermittently dividing all the redistribution layers along the cutting trajectory to partially disconnect all the redistribution layers in the direction of extension of the cutting trajectory.

[0031] In one specific embodiment, the partially cut area includes holes and connecting blocks arranged alternately along the direction of the cutting trajectory, wherein the holes penetrate all or part of the redistribution layers.

[0032] In one specific embodiment, the holes located in different layers in a direction perpendicular to the glass core layer overlap or are misaligned.

[0033] In one specific embodiment, the step of forming a multilayer stacked unit stacked in a direction perpendicular to the glass core layer above the substrate unit further includes: forming the multilayer stacked unit stacked on both the upper and lower surfaces of the substrate unit of the glass core layer.

[0034] In one specific embodiment, the step of forming a multilayer stacked unit above the substrate unit in a direction perpendicular to the glass core layer further includes: the multilayer stacked units formed on the upper and lower surfaces of the same substrate unit are arranged symmetrically with the plane where the substrate unit is located as the symmetrical plane.

[0035] In one specific embodiment, the step of cutting the glass core layer along the cutting path further includes: cutting the glass core layer using mechanical cutting or laser cutting processes.

[0036] In one specific embodiment, in the step of cutting the glass core layer using a mechanical cutting process, the cutting blade is a resin blade.

[0037] In the glass substrate fabrication method provided by the specific embodiments of the present invention, when forming each layer of the stacked units, the stacked units above adjacent substrate units are completely or partially cut off. Ultimately, after forming multiple stacked units, the area above the cutting path is not covered by all the stacked units. That is, in the glass substrate fabrication method provided by the specific embodiments of the present invention, when forming the stacked structure above and / or below the glass core layer, the cutting process is performed multiple times as the process proceeds. After forming multiple stacked units, all redistribution layers above the cutting path are cut off, or partially cut off. In the cutting step, only the glass core layer is cut, or only the glass core layer and part of the redistribution layers are cut. This avoids the cracking of the glass core layer caused by stress release from simultaneously cutting multiple complete redistribution layers, as is common in existing composite tool cutting processes. It also avoids the need for protective adhesive due to exposed glass edges in existing laser-mechanical composite cutting processes. The glass substrate fabrication method provided by the specific embodiments of the present invention avoids the breakage of the glass core layer, thereby reducing the breakage rate of the glass substrate and improving the cutting yield of the glass substrate. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the 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.

[0039] Figure 1 This is a schematic diagram of an existing glass substrate; Figure 2 This is a schematic diagram of the resin layer after the upper and lower surfaces of the glass core are cut using a metal blade. Figure 3 This is a schematic diagram of the glass core layer after it has been cut using a resin cutter. Figure 4 This is a schematic diagram of the existing resin layer after laser ablation; Figure 5 This is another schematic diagram of the glass core layer after it has been cut using a resin knife; Figure 6 This is a schematic diagram of an existing method of using protective adhesive to protect the edges of the glass core layer; Figure 7 This is a schematic diagram of the steps of a glass substrate preparation method provided in a specific embodiment of the present invention; Figure 8 This is a cross-sectional schematic diagram of the glass plate in the glass substrate preparation method provided by a specific embodiment of the present invention; Figure 9 This is a cross-sectional schematic diagram of the glass substrate after modification of the area where through holes need to be formed in the glass substrate preparation method provided in a specific embodiment of the present invention. Figure 10 This is a cross-sectional schematic diagram of the glass substrate preparation method provided in a specific embodiment of the present invention after the formation of vias; Figure 11 This is a cross-sectional schematic diagram of the glass substrate preparation method provided in a specific embodiment of the present invention after the formation of the metal layer; Figure 12 This is a cross-sectional schematic diagram of the glass core layer in a glass substrate preparation method provided by a specific embodiment of the present invention; Figure 13 This is a top view schematic diagram of the glass core layer in the glass substrate preparation method provided by a specific embodiment of the present invention; Figure 14 This is a cross-sectional schematic diagram of the glass substrate preparation method provided in a specific embodiment of the present invention after the bottom insulating layer is formed on the upper and lower surfaces of the glass core layer; Figure 15 This is a top view schematic diagram of the glass substrate preparation method provided in a specific embodiment of the present invention after the bottom insulating layer is formed on the upper and lower surfaces of the glass core layer; Figure 16 This is a cross-sectional schematic diagram of the glass substrate preparation method provided by a specific embodiment of the present invention, in which a bottom-level conductive connection structure is formed in the bottom-level insulating layer and a bottom-level conductive line layer is formed on the bottom-level insulating layer. Figure 17 This is a top view schematic diagram of the glass substrate preparation method provided by a specific embodiment of the present invention, in which a bottom conductive connection structure is formed in the bottom insulating layer and a bottom conductive line layer is formed on the bottom insulating layer. Figure 18 This is a cross-sectional schematic diagram of the glass substrate preparation method provided by a specific embodiment of the present invention after the formation of the second insulating layer on the bottommost redistribution layer; Figure 19 This is a cross-sectional schematic diagram of the glass substrate preparation method provided in a specific embodiment of the present invention after the formation of the second redistribution layer; Figure 20 This is a cross-sectional schematic diagram of a multilayer redistribution layer formed in a glass substrate preparation method according to a specific embodiment of the present invention, which is stacked along the direction perpendicular to the glass core layer. Figure 21 This is a top view schematic diagram of a glass substrate preparation method provided by a specific embodiment of the present invention, in which multiple redistribution layers are stacked along the direction perpendicular to the glass core layer. Figure 22 This is a cross-sectional schematic diagram of the formation of the bottommost stacked unit in the glass substrate preparation method provided by a specific embodiment of the present invention; Figure 23 This is a top view schematic diagram of the formation of the bottommost stacked unit in the glass substrate preparation method provided by a specific embodiment of the present invention; Figure 24 This is a cross-sectional schematic diagram of the formation of a second stacked unit in a glass substrate preparation method provided by a specific embodiment of the present invention; Figure 25 This is a cross-sectional schematic diagram of the formation of multilayer stacked units in a glass substrate preparation method provided by a specific embodiment of the present invention; Figure 26 This is a cross-sectional schematic diagram of a glass substrate formed in a glass substrate preparation method provided in a specific embodiment of the present invention; Figure 27 This is a cross-sectional schematic diagram of the formation of the bottommost stacked unit in a glass substrate preparation method provided by another specific embodiment of the present invention; Figure 28 This is a cross-sectional schematic diagram of the formation of a second stacked unit in a glass substrate preparation method provided by another specific embodiment of the present invention; Figure 29 This is a cross-sectional schematic diagram of the formation of multilayer stacked units in a glass substrate preparation method provided by another specific embodiment of the present invention; Figure 30 This is a cross-sectional schematic diagram of the formation of the bottommost stacked unit in a glass substrate preparation method provided in another specific embodiment of the present invention; Figure 31 This is a top view schematic diagram of the formation of the bottommost stacked unit in a glass substrate preparation method provided in another specific embodiment of the present invention; Figure 32 This is a cross-sectional schematic diagram of the formation of a second stacked unit in a glass substrate preparation method provided in another specific embodiment of the present invention.

[0040] Explanation of reference numerals in the attached figures: 100. Glass core layer; 101. Glass through-hole; 200. Resin layer; 201. Sublayer; 202. Stepped microporous structure; 300. Protective adhesive; 700, Glass core layer; 701, Cutting track; 702, Substrate unit; 703, Glass plate; 704, Glass via; 705, Upper conductive layer; 706, Lower conductive layer; 707, Via; 708, Modified area; 709, Metal layer; 710, Seed layer; 711, Upper dielectric layer; 712, Lower dielectric layer; 800, Stacking unit; 801, Redistribution unit; 802, Insulating unit; 803, Conductive circuit unit; 804, Conductive connection structure; 805, Redistribution layer; 810, Bottom stacking unit; 811, Bottom redistribution layer; 812, Bottom insulating layer; 813, Bottom conductive circuit layer; 814, Bottom conductive connection structure; 820, Second stacking unit; 821, Second redistribution layer; 822, Second insulating layer; 823, Second conductive circuit layer; 824, Second conductive connection structure; 830, Glass substrate; 840, Cut channel; 900, 910, All cut areas; 920, 930, 940, 980, Partial cut areas; 941, 951, Holes; 952, Connecting blocks; 970, Cutting trajectory. Detailed Implementation

[0041] The specific embodiments of the glass substrate preparation method provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0042] Please see Figure 7 The preparation method includes the following steps: Step S70, fabricating a glass core layer, wherein the glass core layer is divided into multiple substrate units by a dicing channel; Step S71, forming a multi-layer stacked unit above the substrate unit in a direction perpendicular to the glass core layer, wherein the stacked unit includes a multi-layer redistribution unit stacked in a direction perpendicular to the glass core layer, wherein when forming each layer of the stacked unit, the stacked units above adjacent substrate units are completely or partially cut off; Step S72, cutting the remaining area between the glass core layer and the stacked units along the dicing channel to form an independent glass substrate.

[0043] The glass substrate fabrication method provided in this invention, during the formation of a stacked structure above and / or below the glass core layer, involves multiple cutting processes as the process progresses. After forming a multi-layered stacked unit, all redistribution layers above the cutting path are cut off, or partially cut off. In the cutting step, only the glass core layer or only the glass core layer and a portion of the redistribution layers are cut. This avoids the cracking of the glass core layer caused by stress release from simultaneously cutting multiple complete redistribution layers, as seen in existing composite tool cutting processes. It also avoids the need for protective adhesive due to exposed glass edges in existing laser-mechanical composite cutting processes. The glass substrate fabrication method provided in this invention avoids glass core layer breakage, thereby reducing the glass substrate fragmentation rate and improving the glass substrate cutting yield. Furthermore, the glass substrate fabrication method provided in this invention cleverly avoids cutting all redistribution layers in the final cutting process by progressively cutting multiple redistribution layers during the process, thus preventing glass core layer breakage, reducing the glass substrate fragmentation rate, and improving the glass substrate cutting yield.

[0044] Figures 8-26 This is a process flow diagram of a glass substrate preparation method provided in a specific embodiment of the present invention.

[0045] Please see Figure 7 , Figure 12 and Figure 13 In step S70, a glass core layer 700 is fabricated, which is divided into multiple substrate units 702 by a cutting channel 701.

[0046] The scribe line 701 is a preset cutting path marker, not a structure that physically separates the glass core layer 700. It can be a scribing line or a shallow groove. Its core function is to form a guide line through a specific process, providing a precise cutting reference for the cutting equipment. The width of the scribe line 701 can be set according to the required width for subsequent cutting processes. In one specific embodiment, the width of the scribe line 701 is the same as, or within the tolerance range of, the width of the cutting blade used in the subsequent cutting process.

[0047] The dicing groove 701 divides the glass core layer 700 into multiple substrate units 702, with the dicing groove 701 separating adjacent substrate units 702. The substrate units 702 are arranged in an array parallel to the surface of the glass core layer 700, such as... Figure 13 As shown, the substrate units 702 are arranged in an array along the X and Y directions.

[0048] As an example, a specific embodiment of the present invention provides a method for fabricating the glass core layer 700. The method for fabricating the glass core layer 700 includes the following steps: Please see Figure 8 , providing glass plate 703. The uncoated soda-lime glass plate 703 is a common glass substrate without surface coating treatment. In this specific embodiment, the glass plate 703 is a large-size glass plate, which can be cut into multiple units in a subsequent cutting process to form a single independent glass substrate. The glass plate 703 includes an upper surface and a lower surface disposed opposite to each other.

[0049] Please see Figure 12 and Figure 13 A glass through-hole 704 penetrating the glass plate 703, an upper conductive layer 705 located on the upper surface of the glass plate 703, and a lower conductive layer 706 located on the lower surface of the glass plate 703 are formed on the glass plate 703. The upper conductive layer 705 is electrically connected to the lower conductive layer 706 through the glass through-hole 704. In some specific embodiments, blind holes (not shown in the figures) are also formed in this step on the surface of the glass plate 703. The blind holes have conductive structures to realize interconnection within the upper conductive layer 705 and the lower conductive layer 706.

[0050] The through-glass via (TGV) 704 is a vertical conductive structure penetrating the glass plate 703. Its upper end is connected to the upper conductive layer 705, and its lower end is connected to the lower conductive layer 706, thereby realizing the electrical connection between the upper conductive layer 705 and the lower conductive layer 706. The upper conductive layer 705 includes a plurality of upper conductive pads (not shown in the figures) formed on the upper surface of the glass plate 703. The upper conductive pads can be electrically connected to the redistribution units 801 subsequently formed on the upper conductive layer 705 to realize the interconnection between different redistribution units 801. The upper conductive pads can also be connected to the upper end of the through-glass via 704. The lower conductive layer 706 includes a plurality of lower conductive pads (not shown in the figures) formed on the lower surface of the glass plate 703. The lower conductive pads can be electrically connected to the redistribution units 801 subsequently formed on the lower conductive layer 706 to realize the interconnection between different redistribution units 801. The lower conductive pads can also be connected to the lower end of the glass through hole 704.

[0051] In one specific embodiment, the step of forming a glass through-hole 704 penetrating the glass plate 703, an upper conductive layer 705 located on the upper surface of the glass plate 703, and a lower conductive layer 706 located on the lower surface of the glass plate 703 further includes: Please see Figure 10 A via 707 is formed through the glass plate 703. The via 707 penetrates the glass plate 703, and multiple vias 707 are arranged in the glass plate 703 as required. In one specific embodiment, the via 707 can be formed in the glass plate 703 by laser etching, chemical etching, or a combination of both. In this step, blind holes (not shown in the figures) that do not penetrate the glass plate 703 can also be formed on the upper and lower surfaces of the glass plate 703 by laser etching, chemical etching, or a combination of both. The method for forming the blind holes is the same as the method for forming the via 707; the following description uses the formation of the via 707 as an example.

[0052] In some embodiments of this invention, the via 707 is formed using a combination of laser processing and chemical etching. Specifically, the step of forming the via 707 penetrating the glass plate 703 further includes: Please see Figure 9 The area of ​​the glass plate 703 where the via 707 needs to be formed is modified. In this specific embodiment, the area of ​​the glass plate 703 where the via 707 needs to be formed is laser-modified to form a modified area 708, which is shown as a dashed line in the figure. Laser irradiation changes the chemical activity and physical morphology of the laser-irradiated area through nonlinear absorption, thermal effects, and structural reorganization, thereby forming a selectively etched modified area.

[0053] Please see Figure 10 The modified region 708 is etched to form the via 707. The modified region 708 of the glass plate 703 has different chemical activity and physical morphology from the unmodified region. An etching solution with a high selectivity for both regions can be selected to etch the glass plate 703. The etching solution only etches the modified region 708 and not the unmodified region, thus forming the via 707 penetrating the glass plate 703 in the modified region 708. In this specific embodiment, the modified glass plate 703 is immersed in the etching solution to etch the modified region 708. Immersion treatment allows the etching solution to fully contact the glass plate 703, avoiding edge effects and effectively controlling etching uniformity.

[0054] In some specific embodiments, laser irradiation can be used to directly ablate the area of ​​the glass plate 703 where the via 707 needs to be formed, removing the glass in that area to form the via 707. In other specific embodiments, chemical etching can be used directly to form the via 707. Specifically, a patterned mask layer is formed on the upper surface of the glass plate 703, exposing the area of ​​the glass plate 703 where the via 707 needs to be formed; the patterned mask layer is used as a shield to etch the glass plate 703 to form the via 707. As an example, in one specific embodiment, the step of forming a patterned mask layer on the upper surface of the glass plate 703 specifically includes: coating a photoresist layer on the upper surface of the glass plate 703; exposing the photoresist layer; and developing the exposed photoresist layer to form a patterned photoresist layer. This patterned photoresist layer serves as the mask layer.

[0055] After forming the via 707, the preparation method includes: Please refer to [link / reference needed]. Figure 11 A metal layer 709 is formed in the via 707, on the upper and lower surfaces of the glass plate 703. Specifically, this step further includes: A seed layer 710 is formed in the via 707, on the upper and lower surfaces of the glass plate 703. The seed layer 710 covers the inner wall of the via 707, the upper and lower surfaces of the glass plate 703.

[0056] The methods for forming the seed layer 710 mainly include physical vapor deposition (PVD), chemical vapor deposition (CVD), and atomic layer deposition (ALD). The material of the seed layer 710 can be selected from copper-based alloys, titanium / titanium nitride, nickel / tungsten alloys, etc.

[0057] The seed layer 710 serves as the initial conductive layer for electroplating, providing a uniform current distribution and preventing dendritic crystal formation caused by excessively high local current density in the electroplating solution. Furthermore, through mechanical interlocking and chemical bonding, it firmly bonds the subsequently electroplated metal layer 709 to the glass plate 703. In some specific embodiments, the seed layer 710 can also prevent metal atoms from diffusing into the glass plate 703, avoiding the formation of a brittle metal-glass interface layer and improving the reliability of the glass substrate.

[0058] In one specific embodiment, before the step of forming the seed layer 710 on the upper and lower surfaces of the glass plate 703 in the via 707, the method further includes: performing interface optimization treatment on the upper and lower surfaces of the glass plate 703. For example, plasma cleaning is performed on the upper and lower surfaces of the glass plate 703 to remove hydroxyl groups on the glass surface and improve the affinity of the interface; chemical passivation is performed on the upper and lower surfaces of the glass plate 703 to improve the wettability of the interface, thereby facilitating the deposition of the seed layer 710.

[0059] Please see Figure 11 An electroplating process is performed to form the metal layer 709 on the seed layer 710. This step uses the seed layer 710 as the initial conductive layer for electroplating, thereby forming the metal layer 709 on the seed layer 710. The selection of the material for the metal layer 709 needs to comprehensively consider conductivity, corrosion resistance, mechanical strength, and process compatibility. In some specific embodiments, the material of the metal layer 709 may be copper, alloy materials, composite metal materials, etc.

[0060] In one specific embodiment, before performing the electroplating process, the seed layer 710 is first surface-cleaned, for example, by plasma cleaning, to improve the adhesion between the seed layer 710 and the metal layer 709. In another specific embodiment, the step of performing the electroplating process to form the metal layer 709 on the seed layer 710 further includes performing a baking process after electroplating. The advantages of the baking process are that it removes residual solvents and moisture; hydrogen evolution during electroplating can cause metal lattice distortion, and baking promotes the diffusion of hydrogen atoms to the surface to escape, eliminating the risk of hydrogen embrittlement; it promotes the interfacial diffusion reaction between the metal layer 709 and the seed layer 710, forming a metallurgical bond and optimizing the adhesion between the metal layer 709 and the seed layer 710; and at high temperatures, the internal stress of the metal layer 709 is released, the porosity of the metal layer 709 is reduced, and the density of the metal layer 709 is improved.

[0061] After the metal layer 709 is formed on the upper and lower surfaces of the glass plate 703 in the via 707, the metal layer 709 on the upper and lower surfaces of the glass plate 703 is patterned to form the upper conductive layer 705 and the lower conductive layer 706. The metal layer 709 located in the via 707 serves as the glass through-hole 704. The glass through-hole 704 is electrically connected to the upper conductive layer 705 and the lower conductive layer 706. Please refer to [link to previous text]. Figure 12 and Figure 13In one specific embodiment, during the step of patterning the metal layer 709 on the upper and lower surfaces of the glass plate 703, the seed layer 710 is patterned simultaneously. The seed layer 710 overlaps with the metal layer 709 in a direction perpendicular to the upper and lower surfaces of the glass plate 703, together serving as the conductive structure of the glass core layer 700.

[0062] As an example, the step of patterning the metal layer 709 on the upper and lower surfaces of the glass plate 703 further includes: forming a patterned mask layer on the surface of the metal layer 709, the mask layer having an opening that exposes the area of ​​the metal layer 709 to be removed; removing the metal layer 709 along the opening, the remaining metal layer 709 serving as the upper conductive layer 705 and the lower conductive layer 706; and removing the mask layer to expose the upper conductive layer 705 and the lower conductive layer 706. In one specific embodiment, the mask layer can be removed using processes such as wet chemical dissolution or dry plasma etching.

[0063] Specifically, the steps of patterning the metal layer 709 on the upper and lower surfaces of the glass plate 703 include: firstly, spin-coating or sputtering photoresist to form a mask layer on the surface of the metal layer 709; the mask layer forms openings through exposure and development to expose the wiring areas of the metal layer 709 that need to be removed; then, selectively removing the metal layer 709 along the openings using dry etching or wet etching, and the remaining metal layer 709 forms an upper conductive layer 705 and a lower conductive layer 706; finally, thoroughly removing the remaining mask layer by acetone immersion or oxygen plasma ashing.

[0064] In one specific embodiment, before the step of patterning the metal layer 709 on the upper and lower surfaces of the glass plate 703, the method further includes: thinning the metal layer 709. This step thins the metal layer 709 to a preset thickness before performing the patterning step, so that the thicknesses of the formed upper conductive layer 705 and lower conductive layer 706 meet preset requirements. Methods for thinning the metal layer 709 include processes such as mechanical polishing and chemical mechanical polishing.

[0065] In one specific embodiment, after the step of patterning the metal layer 709 on the upper and lower surfaces of the glass plate 703, the method further includes: forming an upper dielectric layer 711 on the upper surface of the glass plate 703 and forming a lower dielectric layer 712 on the lower surface of the glass plate 703. The upper dielectric layer 711 fills the gaps in the upper conductive layer 705, and the lower dielectric layer 712 fills the gaps in the lower conductive layer 706. (See also...) Figure 12 and Figure 13The materials of the upper dielectric layer 711 and the lower dielectric layer 712 can be selected from silicon oxide, silicon nitride, silicon oxynitride, high dielectric constant materials, organic materials, etc. The methods for forming the upper dielectric layer 711 and the lower dielectric layer 712 include physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), etc.

[0066] In one specific embodiment, the step of forming an upper dielectric layer 711 on the upper surface of the glass plate 703 and a lower dielectric layer 712 on the lower surface of the glass plate 703 further includes: forming a dielectric material layer, the dielectric material layer covering the upper surface of the glass plate 703 and the upper conductive layer 705, the lower surface of the glass plate 703 and the lower conductive layer 706; thinning the dielectric material layer, using the upper conductive layer 705 and the lower conductive layer 706 as stop layers, to form the upper dielectric layer 711 and the lower dielectric layer 712.

[0067] In the above specific embodiment, after the metal layer 709 is formed on the seed layer 710, the metal layer 709 and the seed layer 710 are simultaneously patterned to form the upper conductive layer 705 and the seed layer located under the upper conductive layer 705, the lower conductive layer 706 and the seed layer located under the lower conductive layer 706.

[0068] In another specific embodiment, after the seed layer 710 is formed, the seed layer 710 is first patterned to form the required conductive area, and then the metal layer 709 is formed on the patterned seed layer 710. The metal layer 709 does not need to be patterned again, and the upper conductive layer 705 and the lower conductive layer 706 can be formed directly on the seed layer. Specifically, the step of forming a glass through-hole 704 penetrating the glass plate 703, an upper conductive layer 705 located on the upper surface of the glass plate 703, and a lower conductive layer 706 located on the lower surface of the glass plate 703 further includes: forming a via 707 penetrating the glass plate 703; forming a seed layer 710 in the via 707, on the upper surface and the lower surface of the glass plate 703; patterning the seed layer 710, retaining the areas where the upper conductive layer 705 and the lower conductive layer 706 need to be formed, and the seed layer 710 in the via 707; performing an electroplating process to form the glass through-hole 704, the upper conductive layer 705, and the lower conductive layer 706 on the seed layer 710, wherein the glass through-hole 704 is electrically connected to the upper conductive layer 705 and the lower conductive layer 706.

[0069] The above specific embodiments illustrate a method for forming a glass through-hole 704 penetrating the glass plate 703, an upper conductive layer 705 located on the upper surface of the glass plate 703, and a lower conductive layer 706 located on the lower surface of the glass plate 703. In another specific embodiment, after forming the through-hole 707, a metal layer can be deposited, and then the glass through-hole 704, the upper conductive layer 705, and the lower conductive layer 706 can be directly formed by laser ablation. In another specific embodiment, after forming the through-hole 707, the glass through-hole 704, the upper conductive layer 705, and the lower conductive layer 706 can be directly formed by printing. In yet another specific embodiment, after forming the glass through-hole 704, the upper conductive layer 705 and the lower conductive layer 706 can be formed by bonding and debonding processes.

[0070] Please see Figure 7 and Figure 25 In step S71, a multilayer stacked unit 800 is formed above the substrate unit 702 in a direction perpendicular to the glass core layer 700. The stacked unit 800 includes multiple layers of redistribution units 801 stacked in a direction perpendicular to the glass core layer 700. When forming each layer of the stacked unit 800, the stacked units 800 above adjacent substrate units 702 are completely or partially cut off. In one specific embodiment, the number of redistribution units 801 included in different layers of the stacked unit 800 can be different to adapt to actual process requirements. (The text repeats itself here, so the translation reflects that.) Figure 25 The Z direction in the equation.

[0071] This step, in the process of fabricating the stacked unit 800, employs a layer-by-layer construction process, specifically including: the first layer formation step: forming the bottommost stacked unit 810 (marked on) on the surface of the substrate unit 702. Figure 22 The adjacent bottommost stacked units 810 are all or partially cut off, and this area is directly opposite the cut track 701; interlayer stacking step: the second to Nth stacked units are stacked sequentially on the bottommost stacked units 810, and the area between the stacked units 800 above the adjacent substrate units in each layer is all or partially cut off, and the all or partially cut off areas between the stacked units of adjacent layers are directly opposite, so that after the final stacked multilayer stacked units 800 are formed, all redistribution layers above the cut track 701 are cut off, or all are partially cut off.

[0072] The glass substrate fabrication method provided in the specific embodiments of the present invention, through the above-mentioned interlayer stacking process, ensures that after forming a stacked multilayer stacked unit, all redistribution layers above the dicing track are cut off, or partially cut off. When all redistribution layers above the dicing track are cut off, the dicing track 701 is fully exposed. When all redistribution layers above the dicing track are partially cut off, the thickness of all redistribution layers above the dicing track 701 is reduced, or the connection strength of all redistribution layers is reduced. In contrast, in the conventional process, after forming a stacked multilayer stacked unit, all redistribution layers above the dicing track 701 of the glass core layer 700 maintain their original thickness and connection strength.

[0073] In some specific embodiments, the step of forming a multilayer stacked unit 800 stacked in a direction perpendicular to the glass core layer 700 above the substrate unit 702 further includes: forming the multilayer stacked unit 800 stacked in a direction perpendicular to the glass core layer 700 on both the upper and lower surfaces of the substrate unit 702 of the glass core layer 700, wherein the stacked unit 800 is formed on the upper conductive layer 705 and / or the lower conductive layer 706. Specifically, in one specific embodiment, as... Figure 25 As shown, the stacking unit 800 is formed on the upper conductive layer 705 and the lower conductive layer 706; in another specific embodiment, the stacking unit 800 is formed only on the upper conductive layer 705; in yet another specific embodiment, the stacking unit 800 is formed only on the upper and lower conductive layers 706; the position of the stacking unit 800 can be set according to the requirements of the final glass substrate.

[0074] In one specific embodiment, the multilayer stacked units 800 formed on the upper and lower surfaces of the same substrate unit 702 are symmetrically arranged with the plane of the substrate unit 702 as the plane of symmetry. The exposed areas of the cleavage paths of two adjacent stacked units 800 extend along the cutting direction of the cleavage path 701 on both sides of the plane of symmetry and are symmetrically arranged with the plane of the substrate unit 702 as the plane of symmetry. This ensures that when cutting the glass core layer 700 in the subsequent step of cutting along the cutting direction, the stacked units 800 that have been misaligned will not be cut, further improving the glass substrate cutting yield.

[0075] The stacking unit 800 includes multiple redistribution units 801 stacked along a direction perpendicular to the glass core layer 700. The redistribution units 801 serve as an intermediate dielectric structure for interconnecting the glass core layer 700 with external chips. Each redistribution unit 801 includes an insulating unit 802 and a conductive line unit 803 disposed on the insulating unit 802. The insulating unit 802 serves as a dielectric isolation, forming an insulating barrier to effectively suppress signal crosstalk and alleviate the thermal expansion coefficient mismatch between the glass core layer 700 and the metal circuit. The conductive line unit 803 provides conductive lines to achieve electrical interconnection between the glass core layer 700 and external chips.

[0076] In one specific embodiment, the insulating unit 802 is an organic resin film unit, including but not limited to polyimide and electronic-grade resin-based film materials (such as ABF layers). The conductive circuit unit 803 is made of copper, alloy materials, composite metal materials, etc.

[0077] A specific embodiment of the present invention provides a method for forming each layer of the stacked units 800. Specifically, the method for forming each layer of the stacked units 800 includes: forming multiple redistribution layers stacked in a direction perpendicular to the glass core layer 700 above the substrate unit 702; dividing the redistribution layers along a cutting trajectory 970 to form multiple layers of the redistribution units 801, such that the stacked units above adjacent substrate units are completely or partially cut off, and the cutting trajectory 970 is the same as the trajectory of the dicing path. The redistribution units 801 adjacent in directions parallel to the glass core layer 700 (as shown in the X and Y directions) are completely or partially cut off. After forming each layer of the stacked units 800, the redistribution layers above the dicing path 701 of the glass core layer 700 are all cut off, or all are partially cut off.

[0078] In one specific embodiment, the method for forming each of the redistribution layers in the step of forming multiple redistribution layers stacked in a direction perpendicular to the glass core layer above the substrate unit includes: An insulating layer is formed over the substrate unit 702. In this step, the insulating layer is not segmented and covers the entire surface above the glass core layer 700.

[0079] In one specific embodiment, the method for forming an insulating layer above the substrate unit 702 includes: providing a single sheet of insulating material; and pressing the insulating material layer onto the glass core layer as the insulating layer. This method avoids displacement that occurs when individually mounting insulating units, resulting in higher positioning accuracy. In one specific embodiment, the pressing method for pressing the insulating material layer onto the glass core layer is hot pressing. The insulating layer is softened by heating while mechanical pressure is applied, utilizing intermolecular forces (van der Waals forces) or chemical bonds (such as epoxy resin crosslinking) to achieve adhesion between the insulating layer and the underlying structure.

[0080] A conductive connection structure 804 is formed in the insulating layer, and a conductive circuit layer is formed on the insulating layer, the conductive circuit layer being electrically connected to the conductive connection structure 804. In this step, the conductive circuit layer is not segmented and covers the entire surface above the glass core layer 700.

[0081] In one specific embodiment, the steps of forming a conductive connection structure 804 in the insulating layer and forming a conductive circuit layer on the insulating layer further include: forming a via in the insulating layer; forming a conductive material layer on the insulating layer, the conductive material layer further filling the via; patterning the conductive material layer to form the conductive circuit layer, wherein the conductive material layer in the via serves as the conductive connection structure 804.

[0082] In one specific embodiment, prior to the step of forming a conductive material layer on the insulating layer, the method further includes: forming a seed layer on the insulating layer, the seed layer also covering the inner wall of the via; the step of forming a conductive material layer on the insulating layer further includes: performing an electroplating process to form the conductive material layer on the seed layer.

[0083] Repeat the steps of forming the insulating layer, forming the conductive connection structure 804, and forming the conductive circuit layer to form multiple layers of the redistribution layer stacked in a direction perpendicular to the glass core layer. In two adjacent redistribution layers, the conductive circuit layer of the upper redistribution layer is electrically connected to the conductive circuit layer of the lower redistribution layer via the conductive connection structure 804.

[0084] After forming multiple redistribution layers, multiple insulating layers and multiple conductive lines are divided along a cutting trajectory 970 to form insulating units 802 and conductive lines 803, such that the insulating units 802 and conductive lines 803 above adjacent substrate units 702 are completely or partially cut off. Above the same substrate unit 702, the insulating units 802, conductive connection structures 804, and conductive lines 802 located on the same layer together serve as redistribution units 801. Multiple redistribution units 801 are stacked along a direction perpendicular to the glass core layer 700 and form a stacking unit 800. In one specific embodiment, laser cutting or mechanical cutting processes are used to divide part or all of the insulating layers and conductive lines along the cutting trajectory 970.

[0085] As an example, a specific embodiment of the present invention provides a method for forming a multilayer stacked unit 800 stacked above the substrate unit 702 in a direction perpendicular to the glass core layer 700. When forming each layer of the stacked unit, the stacked units on adjacent substrate units are completely cut off, and the width of the completely cut off region is less than or equal to the width of the dicing channel 701. In this specific embodiment, the width of the completely cut off region is equal to the width of the dicing channel 701 as an example. The method for forming the multilayer stacked unit 800 includes: Please see Figure 22 and Figure 23 A bottom layer stacked unit 810 is formed on the upper and lower surfaces of the substrate unit 702. In this specific embodiment, a completely cut-off region 900 is formed between the bottom layer stacked units 810 on adjacent substrate units 702. This step includes: A bottom redistribution layer 811 (marked as shown in the diagram) is formed on the upper and lower surfaces of the substrate unit 702. Figure 16 (in Chinese), including the following steps: Please see Figure 14 and Figure 15 A bottom insulating layer 812 is formed on the upper and lower surfaces of the glass core layer 700, covering the entire upper and lower surfaces of the glass core layer 700. In this step, a single sheet of insulating material is first provided, and then the insulating material layer is pressed onto the entire upper and lower surfaces of the glass core layer 700 using a thermoforming method, forming the bottom insulating layer 812. The dimensions of the insulating material layer can be the same as the dimensions of the glass plate 703. The insulating material layer is an organic resin material layer.

[0086] Please see Figure 16 and Figure 17A bottom conductive connection structure 814 is formed in the bottom insulating layer 812, and a bottom conductive line layer 813 is formed on the bottom insulating layer 812. As an example, the method for forming the bottom conductive connection structure 814 and the bottom conductive line layer 813 in this step includes: forming a via in the bottom insulating layer 812; forming a seed layer on the bottom insulating layer 812, the seed layer also covering the inner wall of the via; performing an electroplating process to form a conductive material layer on the seed layer; patterning the conductive material layer to form the bottom conductive line layer 813, wherein the conductive material layer within the via serves as the bottom conductive connection structure 814.

[0087] The bottom insulating layer 812, the bottom conductive connection structure 814, and the bottom conductive line layer 813 serve as the bottom redistribution layer 811. The bottom conductive connection structure 814 is electrically connected to the upper conductive layer 705 or the lower conductive layer 706.

[0088] A second redistribution layer 821 (indicated in) is formed on the bottommost redistribution layer 811. Figure 19 (in Chinese), including the following steps: Please see Figure 18 A second insulating layer 822 is formed on the bottommost redistribution layer 811. The method for forming the second insulating layer 822 in this step is the same as the method for forming the bottommost insulating layer 812.

[0089] Please see Figure 19 A second conductive connection structure 824 is formed in the second insulating layer 822, and a second conductive line layer 823 is formed on the second insulating layer 822. The method for forming the second conductive connection structure 824 in this step is the same as the method for forming the bottom conductive connection structure 814, and the method for forming the second conductive line layer 823 is the same as the method for forming the bottom conductive line layer 813.

[0090] The second insulating layer 822, the second conductive connection structure 824, and the second conductive line layer 823 constitute the second redistribution layer 821. The second conductive connection structure 824 is electrically connected to the bottom conductive line layer 813.

[0091] Please see Figure 20 and Figure 21 Repeat the steps described above to form the second redistribution layer 821, forming the third to Nth redistribution layers, and finally forming a multi-layer redistribution layer 805 stacked in a direction perpendicular to the glass core layer 700.

[0092] Please see Figure 22 and Figure 23 Along a cutting trajectory 970 (marked at) Figure 21 The redistribution layer 805 is divided to form multiple redistribution units 801, such that the bottommost stacked units 810 above adjacent substrate units 702 form a complete cut-off region 900, and the cutting trajectory 970 is the same as the trajectory of the cutting path 701. Multiple redistribution units 801 located on the upper surface of the same substrate unit 702 constitute one bottommost stacked unit 810, and similarly, multiple redistribution units 801 located on the lower surface of the same substrate unit 702 constitute one bottommost stacked unit 810. In directions parallel to the glass core layer 700 (as shown in the X and Y directions), adjacent bottommost stacked units 810 form a complete cut-off region 900, which exposes the cutting path 701 of the glass core layer 700.

[0093] After forming the bottommost stacked unit 810, a second stacked unit 820 is formed on the bottommost stacked unit 810. In this specific embodiment, the area between the second stacked units 820 on adjacent substrate units 702 is a completely cut-off region 910. Please refer to [link / reference]. Figure 24 This step includes: Multiple redistribution layers are formed on the bottommost stacked unit 810. The method for forming the redistribution layers is the same as the method for forming the second redistribution layer 821.

[0094] The redistribution layer 805 is divided along a cutting trajectory 970 using a mechanical cutting process to form multiple redistribution units 801, such that the second-layer stacked units 820 above adjacent substrate units 702 are completely cut off 910. Multiple redistribution units 801 located on the upper surface of the same substrate unit 702 constitute one second-layer stacked unit 820, and similarly, multiple redistribution units 801 located on the lower surface of the same substrate unit 702 constitute one second-layer stacked unit 820. In directions parallel to the glass core layer 700 (as shown in the X and Y directions), adjacent second-layer stacked units 820 are completely cut off 910, exposing the cutting paths 701 of the glass core layer 700. The completely cut off 900 of the bottommost stacked unit 810 is continuous with the completely cut off 910 of the second-layer stacked unit 820.

[0095] Please see Figure 25The steps for forming the second stacked unit 820 are repeated to form the third to Nth stacked units, ultimately forming a multi-layer stacked unit 800 stacked along a direction perpendicular to the glass core layer 700. The entire cut area of ​​the finally formed multi-layer stacked unit 800 forms a continuous through-cut channel 840 in three-dimensional space, exposing the cut path 701 of the glass core layer 700.

[0096] Please see Figure 7 and Figure 26 In step S72, the glass core layer 700 is cut along the cutting path 701 to form an independent glass substrate 830.

[0097] The cutting channel 840 of the stacked multilayer stacked unit 800 exposes the cutting path 701. Therefore, when performing the cutting process, it is only necessary to go deep into the cutting channel 840 in the cutting direction and cut the glass core layer 700 along the cutting path 701, which effectively reduces the breakage rate of the glass substrate and significantly improves the cutting yield of the glass substrate.

[0098] In one specific embodiment, the step of cutting the glass core layer 700 along the cutting path 701 further includes: cutting the glass core layer 700 using mechanical cutting or laser cutting processes. In one specific embodiment, in the step of cutting the glass core layer 700 using mechanical cutting processes, the cutting blade is a resin blade. Resin blades have excellent elasticity, absorbing cutting stress through elastic deformation, reducing the roughness of the cut surface of the glass core layer 700, and effectively reducing the density of microcracks.

[0099] Compared to traditional processes that require cutting redistribution layers and glass core layer 700 after multi-layer stacking, the glass substrate preparation method provided in this invention forms cutting channels 840 simultaneously during layer-by-layer construction. This effectively avoids the problems of cracks in the glass core layer 700 and the need for protective adhesive to be applied to exposed glass edges after cutting, effectively reducing the breakage rate of the glass substrate and significantly improving the glass substrate cutting yield.

[0100] In other specific embodiments, when forming each layer of the stacked units, there is a partially cut-off region between the stacked units on adjacent substrate units. By setting the partially cut-off region, the stress of the stacked units is released layer by layer, effectively avoiding the problems of cracks in the glass core layer 700 and the need to apply protective adhesive to the exposed glass edges after cutting. This effectively reduces the breakage rate of the glass substrate and significantly improves the glass substrate cutting yield.

[0101] As an example, another specific embodiment of the present invention provides a method for forming multiple layers of the stacked units 800, wherein, when forming each layer of the stacked units, there is a partially cut-off region between the stacked units on adjacent substrate units. In this specific embodiment, the method for creating a partially cut-off region between the stacked units on adjacent substrate units includes: cutting all redistribution layers along the cutting trajectory 970 to a predetermined depth, so that the redistribution layers are partially disconnected, thereby forming the stacked units 800. Specifically, the method for forming multiple layers of the stacked units 800 provided in this specific embodiment includes the following steps: The bottommost stacked unit 810 (marked as) is formed on the upper and lower surfaces of the substrate unit 702. Figure 27 In this specific embodiment, a partially cut-off region 920 is formed between the bottommost stacked units 810 on adjacent substrate units 702. This step includes forming a bottommost insulating layer 812 on the upper and lower surfaces of the glass core layer 700. (See also...) Figure 14 and Figure 15 A bottom-level conductive connection structure 814 is formed in the bottom-level insulating layer 812, and a bottom-level conductive line layer 813 is formed on the bottom-level insulating layer 812. Please refer to [link / reference]. Figure 16 and Figure 17 The bottom insulating layer 812, the bottom conductive connection structure 814, and the bottom conductive line layer 813 are described as the bottom redistribution layer 811.

[0102] A second insulating layer 822 is formed on the bottommost redistribution layer 811. (See also...) Figure 18 A second conductive connection structure 824 is formed in the second insulating layer 822, and a second conductive line layer 823 is formed on the second insulating layer 822. (See also...) Figure 19 The second insulating layer 822, the second conductive connection structure 824, and the second conductive line layer 823 serve as the second redistribution layer 821.

[0103] Repeat the steps described above for forming the second redistribution layer 821 to form the third to Nth redistribution layers, ultimately forming a multi-layer redistribution layer 805 stacked along a direction perpendicular to the glass core layer 700. The multi-layer redistribution layer 805 is a stacked layer; please refer to [link / reference]. Figure 20 and Figure 21 .

[0104] Please see Figure 27All the redistribution layers are divided along the cutting trajectory 970 to a preset depth to form the bottommost stacking unit 810. The stacking layer is partially broken in the direction perpendicular to the glass core layer to form a partially cut region 920 between adjacent bottommost stacking units 810. In this step, multiple redistribution layers can be cut to the preset depth of the stacking layers. The insulating layer and conductive line layer of each redistribution layer are cut, while the insulating layer and conductive line layer of the uncut redistribution layers remain intact. In another specific embodiment, multiple redistribution layers can also be cut to the preset depth of the stacking layers. This preset depth can be located at any position of a single redistribution layer. The insulating layer and conductive line layer of the bottommost redistribution layer in the cut region can be partially cut. For example, the conductive line layer is completely cut while the insulating layer remains intact, or the conductive line layer is partially cut while the insulating layer remains intact, or the conductive line layer is completely cut while the insulating layer is partially cut.

[0105] Please see Figure 28 A second stacking unit 820 is formed on the bottommost stacking unit 810, and a partially cut region 930 is formed between adjacent second stacking units 820. The method for forming the second stacking unit 820 in this step is the same as the method for forming the bottommost stacking unit 810. The partially cut region 930 overlaps with the partially cut region 920 and corresponds to the position of the cutting channel 701.

[0106] Please see Figure 29 Repeat the steps described above to form the second layer of stacked unit 820 to form the third to Nth layer of stacked units 800. The total thickness of the partially cut-off area 980 of the finally formed multi-layer stacked unit 800 is less than the total thickness of the stacked area of ​​the multi-layer stacked unit 800.

[0107] Please see Figure 26 After forming a stacked multilayer stacked unit 800, the glass core layer 700 and the partial cut area between adjacent stacked units 800 are cut along the cutting trajectory 970 and the cutting channel 701 to form an independent glass substrate 830.

[0108] In this specific embodiment, through interlayer stacking technology, after forming multiple stacked units, all stacked units above the cutting path 701 are partially cut layer by layer. On the one hand, the thickness of all stacked units above the cutting path 701 is reduced; on the other hand, the stress of each stacked unit is reduced by partial cutting, thereby reducing stress accumulation. This ensures that in the final cutting step, there is no cracking of the glass core layer caused by the complete stress release from cutting multiple complete redistribution layers simultaneously, as is the case in existing composite tool cutting processes. It also avoids the need for protective adhesive due to exposed glass edges in existing laser-mechanical composite cutting processes. This invention effectively avoids the problems of cracking in the glass core layer 700 and the need for protective adhesive after cutting, effectively reducing the glass substrate breakage rate and significantly improving the glass substrate cutting yield.

[0109] As an example, another specific embodiment of the present invention provides a method for forming multiple layers of the stacked cells 800, wherein, when forming each layer of the stacked cells, there is a partially cut-off region between the stacked cells on adjacent substrate cells. In this specific embodiment, the method for creating a partially cut-off region between the stacked cells on adjacent substrate cells includes: intermittently cutting a redistribution layer along a cutting trajectory 970 to partially disconnect the redistribution layer in the direction of extension of the cutting trajectory 970, thereby forming the stacked cells 800.

[0110] In one specific embodiment, the partially cut area includes holes and connecting blocks alternately arranged along the cutting trajectory 970. The holes release stress on the redistribution layers and reduce their connection strength, thereby preventing the glass core layer from breaking in subsequent cutting steps, thus reducing the glass substrate's breakage rate and improving the cutting yield. The holes penetrate all or part of the redistribution layers; that is, the cutting depth of the holes is the full thickness or part of the thickness of the stacked layer composed of all the redistribution layers. The shape of the holes can be circular, square, serrated, or irregular. In one specific embodiment, the holes located in different layers are staggered in a direction perpendicular to the glass core layer 700.

[0111] Specifically, the method for forming multiple layers of the stacked unit 800 provided in this embodiment includes the following steps: The bottommost redistribution layer 811 is formed on the upper and lower surfaces of the glass core layer 700. (See also...) Figure 16 and Figure 17 A second redistribution layer 821 is formed on the bottommost redistribution layer 811. (See also...) Figure 19Repeat the steps described above for forming the second redistribution layer 821 to form the third to Nth redistribution layers, ultimately forming a multilayer redistribution layer 805 stacked along a direction perpendicular to the glass core layer 700. The multilayer redistribution layer 805 is a stacked layer. (See also...) Figure 20 and Figure 21 .

[0112] Please see Figure 30 and Figure 31 The redistribution layer is intermittently cut along the cutting trajectory 970 to partially break the redistribution layer in the direction of extension of the cutting trajectory 970, forming the bottommost stacking unit 810, and a partially cut region 940 is formed between adjacent bottommost stacking units 810. Specifically, in this step, the stacking layer composed of multiple redistribution layers is intermittently cut along the cutting trajectory 970 to partially break the stacking layer in the direction of extension of the cutting trajectory 970, forming the bottommost stacking unit 810. As an example, the partially cut region 940 between adjacent bottommost stacking units 810 in the direction of extension of the cutting trajectory 970 consists of alternating holes 941 and connecting blocks 942, forming a postage stamp-like structure to reduce the connection strength and stress between two adjacent bottommost stacking units 810. In this specific embodiment, the hole 941 penetrates the bottommost stacking layer, that is, the depth to which the stacking layer is cut is the full thickness of the stacking layer. In some other embodiments, the hole 941 does not penetrate the bottommost stack layer, and the hole 941 extends downward from the surface of the bottommost stack layer to a predetermined depth of the bottommost stack layer, that is, the depth to which the stack layer is cut is a portion of the thickness of the stack layer.

[0113] Please see Figure 32A second stacking unit 820 is formed on the bottommost stacking unit 810. Adjacent second stacking units 820 are partially cut off, and these partially cut off areas include alternating holes 951 and connecting blocks. The method for forming the second stacking unit 820 in this step is the same as that for forming the bottommost stacking unit 810. The partially cut off area 940 of the bottommost stacking unit 810 overlaps with the partially cut off area of ​​the second stacking unit 820 and corresponds to the position of the cutting channel 701. In the direction perpendicular to the glass core layer, the holes 941 in the bottommost stacking unit 810 overlap with the holes 951 in the second stacking unit 820; that is, in the direction perpendicular to the glass core layer 700, the holes 941 in the bottommost stacking unit 810 and the holes 951 in the second stacking unit 820 are either connected or directly opposite each other. In another specific embodiment, the holes 941 in the bottommost stacked unit 810 and the holes 951 in the second stacked unit 820 are staggered in the direction perpendicular to the glass core layer 700, so as to further reduce the stress and connection strength of the final stacked layer composed of multiple stacked units, and reduce the difficulty of subsequent cutting processes.

[0114] Please see Figure 25 Repeat the steps described above to form the second layer stacking unit 820 to form the third to Nth layer stacking units 800. The total thickness of the partially cut-off area of ​​the finally formed multi-layer stacking unit 800 is less than the total thickness of the stacked area of ​​the multi-layer stacking unit 800.

[0115] Please see Figure 26 After forming a stacked multilayer stacked unit 800, the glass core layer 700 and the partial cut area between adjacent stacked units 800 are cut along the cutting trajectory 970 and the cutting channel 701 to form an independent glass substrate 830.

[0116] In this specific embodiment, through an interlayer stacking process, each stacked unit is formed by intermittently cutting the stacked layers above the cutting path into alternating arrangements of holes and connecting blocks. The holes release stress in each redistribution layer, thereby reducing stress accumulation and decreasing the connection strength of the redistribution layers. This eliminates the cracking of the glass core layer caused by the simultaneous cutting of multiple complete redistribution layers, as seen in existing composite tool cutting processes, and also avoids the need for protective adhesive due to exposed glass edges in existing laser-mechanical composite cutting processes. This invention effectively avoids the problems of glass core layer cracking and the need for protective adhesive after glass edge exposure, effectively reducing the glass substrate breakage rate and significantly improving the glass substrate cutting yield. The glass substrate preparation method provided by this invention cleverly utilizes changes in the cutting steps during the process to effectively avoid the risk of glass substrate breakage, reduce the glass substrate breakage rate, and improve the glass substrate cutting yield.

[0117] It should be noted that the terms "comprising" and "having," and their variations, used in this invention document are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence, unless explicitly indicated by the context; it should be understood that such use of data can be interchanged where appropriate. The term "one or more" depends at least in part on the context and can be used to describe features, structures, or characteristics in a singular sense, or in a plural sense to describe combinations of features, structures, or characteristics. The term "based on" can be understood as not necessarily intended to express an exclusive set of factors, but can instead, also at least in part on the context, allow for the presence of other factors that are not necessarily explicitly described. Furthermore, embodiments and features in embodiments of this invention can be combined with each other without conflict. In addition, descriptions of well-known components and technologies have been omitted in the above description to avoid unnecessarily obscuring the concepts of this invention. In the various embodiments described above, each embodiment focuses on its differences from other embodiments; similar / identical parts between embodiments can be referred to mutually.

[0118] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a glass substrate, characterized in that, Includes the following steps: A glass core layer is fabricated, wherein the glass core layer is divided into multiple substrate units by cleaving lines; A multilayer stacked unit is formed above the substrate unit in a direction perpendicular to the glass core layer. The stacked unit includes a multilayer redistribution unit stacked in a direction perpendicular to the glass core layer. When forming each layer of the stacked unit, the stacked units above adjacent substrate units are completely or partially cut off. The remaining area between the glass core layer and the stacked units is cut along the cutting path to form an independent glass substrate.

2. The method for preparing a glass substrate according to claim 1, characterized in that, The method for fabricating the glass core layer further includes the following steps: Provide glass plates; A glass through-hole is formed through the glass plate, an upper conductive layer is located on the upper surface of the glass plate, and a lower conductive layer is located on the lower surface of the glass plate. The upper conductive layer is electrically connected to the lower conductive layer through the glass through-hole. In the step of forming a multilayer stacked unit stacked in a direction perpendicular to the glass core layer above the substrate unit, the stacked unit is formed on the upper conductive layer and / or the lower conductive layer.

3. The method for preparing a glass substrate according to claim 2, characterized in that, The step of forming a glass through-hole, an upper conductive layer on the upper surface of the glass plate, and a lower conductive layer on the lower surface of the glass plate further includes: Forming a through hole through the glass plate; A metal layer is formed in the via, on the upper and lower surfaces of the glass plate; The metal layers on the upper and lower surfaces of the glass plate are patterned to form the upper conductive layer and the lower conductive layer. The metal layer located in the via serves as the glass via, and the glass via is electrically connected to the upper conductive layer and the lower conductive layer.

4. The method for preparing a glass substrate according to claim 3, characterized in that, The step of forming a through-hole through the glass plate further includes: The area of ​​the glass plate where the via needs to be formed is modified. The modified area is etched to form the via.

5. The method for preparing a glass substrate according to claim 4, characterized in that, The step of modifying the area of ​​the glass plate where the via needs to be formed further includes: using laser modification on the area of ​​the glass plate where the via needs to be formed.

6. The method for preparing a glass substrate according to claim 4, characterized in that, The step of etching the modified area further includes immersing the modified glass plate in an etching solution to etch the modified area.

7. The method for preparing a glass substrate according to claim 3, characterized in that, The step of forming a metal layer in the via, on the upper and lower surfaces of the glass plate, further includes: A seed layer is formed in the via, on the upper and lower surfaces of the glass plate; An electroplating process is performed to form the metal layer on the seed layer; In the step of patterning the metal layers on the upper and lower surfaces of the glass plate, the seed layer is patterned simultaneously.

8. The method for preparing a glass substrate according to claim 7, characterized in that, The step of performing an electroplating process to form the metal layer on the seed layer further includes performing a baking process after electroplating.

9. The method for preparing a glass substrate according to claim 7, characterized in that, Before the step of forming a seed layer in the via, on the upper and lower surfaces of the glass plate, the method further includes: performing interface optimization treatment on the upper and lower surfaces of the glass plate.

10. The method for preparing a glass substrate according to claim 3, characterized in that, The step of patterning the metal layers on the upper and lower surfaces of the glass plate further includes: A patterned mask layer is formed on the surface of the metal layer, the mask layer having openings that expose the areas of the metal layer that need to be removed; The metal layer is removed along the opening, and the remaining metal layer serves as the upper conductive layer and the lower conductive layer; Remove the mask layer.

11. The method for preparing a glass substrate according to claim 3, characterized in that, The step of patterning the metal layer on the upper and lower surfaces of the glass plate further includes: thinning the metal layer.

12. The method for preparing a glass substrate according to claim 3, characterized in that, The step of graphically representing the metal layers on the upper and lower surfaces of the glass plate further includes: An upper dielectric layer is formed on the upper surface of the glass plate, and a lower dielectric layer is formed on the lower surface of the glass plate. The upper dielectric layer fills the gaps in the upper conductive layer, and the lower dielectric layer fills the gaps in the lower conductive layer.

13. The method for preparing a glass substrate according to claim 12, characterized in that, The step of forming an upper dielectric layer on the upper surface of the glass plate and forming a lower dielectric layer on the lower surface of the glass plate further includes: A dielectric material layer is formed, which covers the upper surface of the glass plate and the upper conductive layer, the lower surface of the glass plate and the lower conductive layer; The dielectric material layer is thinned, and the upper conductive layer and the lower conductive layer are used as stop layers to form the upper dielectric layer and the lower dielectric layer.

14. The method for preparing a glass substrate according to claim 2, characterized in that, The step of forming a glass through-hole, an upper conductive layer on the upper surface of the glass plate, and a lower conductive layer on the lower surface of the glass plate further includes: Forming a through hole through the glass plate; A seed layer is formed in the via, on the upper and lower surfaces of the glass plate; The seed layer is graphically represented, retaining the areas where the upper and lower conductive layers need to be formed, as well as the seed layer in the via; An electroplating process is performed to form the glass via, the upper conductive layer, and the lower conductive layer on the seed layer, wherein the glass via is electrically connected to the upper conductive layer and the lower conductive layer.

15. The method for preparing a glass substrate according to claim 1, characterized in that, The step of forming each layer of the stacked cells further includes: A multilayer redistribution layer is formed above the substrate unit in a direction perpendicular to the glass core layer; The redistribution layer is divided along a cutting trajectory, such that the stacked units above adjacent substrate units are completely or partially cut off, and the cutting trajectory is the same as the cutting path trajectory.

16. The method for preparing a glass substrate according to claim 15, characterized in that, The method for forming each of the redistribution layers in the step of forming a multilayer redistribution layer stacked in a direction perpendicular to the glass core layer above the substrate unit includes: An insulating layer is formed above the substrate unit; A conductive connection structure is formed in the insulating layer and a conductive circuit layer is formed on the insulating layer, wherein the conductive circuit layer is electrically connected to the conductive connection structure. The step of dividing the redistribution layer along a cutting trajectory further includes: dividing the insulating layer and the conductive line layer along a cutting trajectory to form insulating units and conductive line units, such that the insulating units and conductive line units above adjacent substrate units are all or partially cut off.

17. The method for preparing a glass substrate according to claim 16, characterized in that, The step of forming an insulating layer over the substrate unit further includes: Provide a single layer of insulation material; The insulating material layer is laminated onto the glass core layer to form the insulating layer.

18. The method for preparing a glass substrate according to claim 17, characterized in that, The method of pressing the insulating material layer onto the glass core layer is hot pressing.

19. The method for preparing a glass substrate according to claim 16, characterized in that, The steps of forming a conductive connection structure in the insulating layer and forming a conductive line layer on the insulating layer further include: Through-holes are formed in the insulating layer; A conductive material layer is formed on the insulating layer, and the conductive material layer also fills the via. The conductive material layer is patterned to form the conductive circuit layer, and the conductive material layer within the via serves as the conductive connection structure.

20. The method for preparing a glass substrate according to claim 19, characterized in that, Prior to the step of forming a conductive material layer on the insulating layer, the method further includes: forming a seed layer on the insulating layer, the seed layer also covering the inner wall of the via; The step of forming a conductive material layer on the insulating layer further includes performing an electroplating process to form the conductive material layer on the seed layer.

21. The method for preparing a glass substrate according to claim 16, characterized in that, The insulating layer is an organic resin film.

22. The method for preparing a glass substrate according to claim 15, characterized in that, The step of dividing the redistribution layer along a cutting trajectory further includes: dividing part or all of the redistribution layer along the cutting trajectory using laser cutting or mechanical cutting processes.

23. The method for preparing a glass substrate according to claim 15, characterized in that, A method for dividing the redistribution layer along a cutting trajectory such that the stacked cells above adjacent substrate cells are completely cut off includes: dividing all the redistribution layers along the cutting trajectory until the redistribution layers are completely disconnected.

24. The method for preparing a glass substrate according to claim 15, characterized in that, A method for dividing the redistribution layers along a cutting trajectory to create a partially cut-off region between the stacked units above adjacent substrate units includes: dividing all the redistribution layers along the cutting trajectory to a predetermined depth so that all the redistribution layers are partially disconnected.

25. The method for preparing a glass substrate according to claim 15, characterized in that, A method of dividing the redistribution layers along a cutting trajectory to create a partially cut-off region between the stacked cells above adjacent substrate cells includes: intermittently dividing all the redistribution layers along the cutting trajectory to partially disconnect all the redistribution layers in the direction of extension of the cutting trajectory.

26. The method for preparing a glass substrate according to claim 25, characterized in that, The partially cut area includes holes and connecting blocks arranged alternately along the direction of the cutting trajectory, wherein the holes penetrate all or part of the redistribution layers.

27. The method for preparing a glass substrate according to claim 26, characterized in that, The holes in different layers are overlapping or misaligned in the direction perpendicular to the glass core layer.

28. The method for preparing a glass substrate according to claim 1, characterized in that, The step of forming a multilayer stacked unit above the substrate unit in a direction perpendicular to the glass core layer further includes: forming the multilayer stacked unit on both the upper and lower surfaces of the substrate unit of the glass core layer.

29. The method for preparing a glass substrate according to claim 28, characterized in that, The step of forming a multilayer stacked unit above the substrate unit in a direction perpendicular to the glass core layer further includes: the multilayer stacked units formed on the upper and lower surfaces of the same substrate unit are arranged symmetrically with the plane where the substrate unit is located as the plane.

30. The method for preparing a glass substrate according to claim 1, characterized in that, The step of cutting the glass core layer along the cutting path further includes: cutting the glass core layer using mechanical cutting or laser cutting processes.

31. The method for preparing a glass substrate according to claim 30, characterized in that, In the step of cutting the glass core layer using a mechanical cutting process, the cutting blade is a resin blade.

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