A pre-warped glass carrier plate and methods of making and using the same

Abstract

This invention provides a pre-warped glass substrate, its manufacturing method, and its applications. The manufacturing method includes: providing a glass substrate; thermoforming the glass substrate to form a pre-bent shape; and forming a stress layer on at least one surface of the pre-bent glass substrate to adjust the curvature of the glass substrate, thereby obtaining a pre-warped glass substrate with a target curvature. This invention, through a process of "physical shaping as the body and chemical strengthening as the application," constructs a dual control mechanism of "pre-deformation-stress compensation," achieving precise design and thermal stability control of the curvature of the glass substrate. This fundamentally eliminates the macroscopic warping problem caused by material CTE mismatch, realizing the functional integration of deformation control and mechanical strengthening. This glass substrate is applicable to a full range of advanced packaging scenarios with stringent warp control requirements, such as 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking.

Description

Technical Field

[0001] This invention belongs to the field of special glass materials and semiconductor manufacturing, specifically relating to a pre-warped glass substrate, its manufacturing method, and its application. Background Technology

[0002] Against the backdrop of semiconductor technology's development towards heterogeneous integration and packaging, advanced packaging technologies such as 2D, 2.5D (based on silicon interposers or redistribution layers), 3D (based on through-silicon vias (TSVs), fan-out, fan-in, system-in-package (SiP), and wafer-level chip stacking (CoW, WoW) have become core pathways to improve device performance and integration. In these complex packaging structures, glass substrates are typically used as temporary or permanent support substrates to allow for the layer-by-layer construction or bonding of various heterogeneous materials, including silicon chips, organic substrates, epoxy molding compounds (EMC), polymer dielectric layers, metal redistribution layers (RDLs), and microbumps, during wafer-level fabrication.

[0003] However, due to the significant differences in the coefficients of thermal expansion (CTE) of the aforementioned materials, the effective CTE of the laminated structure undergoes dynamic and nonlinear changes during thermal cycling processes such as deposition, curing, and reflow soldering. This results in a severe mismatch with the CTE of the relatively fixed glass substrate, thereby inducing enormous internal stress within the wafer. This stress manifests as time-varying, unpredictable macroscopic warping at the wafer level.

[0004] This macroscopic warping poses a severe challenge to high-precision manufacturing processes: on the one hand, it leads to a decrease in photolithography overlay accuracy and the generation of solder bridge defects; on the other hand, it increases the void ratio at the thermocompressed bonding (TCB) interface and introduces fragmentation risks during grinding, cutting, and other processes, severely restricting packaging yield, design rules, and equipment compatibility. Currently, traditional flat glass substrates cannot effectively suppress or compensate for this macroscopic warping caused by material CTE mismatch.

[0005] Therefore, how to solve the macroscopic warpage problem caused by material CTE mismatch in the packaging process, and simultaneously improve the yield and reliability of the packaging process, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a pre-warped glass substrate, its manufacturing method, and its applications. This invention utilizes a process of "physical shaping as the foundation and chemical strengthening as the application," constructing a dual control mechanism of "pre-deformation-stress compensation." This achieves precise design and thermal stability control of the glass substrate's curvature, fundamentally eliminating macroscopic warping problems caused by material CTE mismatch. It integrates deformation control and mechanical strengthening functions, ensuring the long-term stability of the pre-warped curvature under high-temperature processes, while significantly improving the mechanical strength of the glass substrate. This glass substrate is suitable for a full range of advanced packaging scenarios with stringent warp control requirements, including 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking, meeting the needs of high-precision advanced packaging processes.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for manufacturing a pre-warped glass substrate, the method comprising the following steps: We provide glass substrates.

[0008] The glass substrate is thermoformed to form a pre-bent shape.

[0009] A stress layer is formed on at least one side surface of a glass carrier having the pre-bent shape to adjust the curvature of the glass carrier, thereby obtaining a pre-warped glass carrier with a target curvature.

[0010] This invention utilizes a process of "physical shaping as the foundation and chemical strengthening as the application" to construct a dual control mechanism of "pre-deformation-stress compensation." This achieves precise design and thermal stability control of the glass substrate's curvature, fundamentally eliminating macroscopic warpage caused by material CTE mismatch. It integrates deformation control and mechanical strengthening, ensuring the long-term stability of the pre-deformation curvature under high-temperature processes while significantly improving the mechanical strength of the glass substrate. This glass substrate is suitable for a full range of advanced packaging scenarios with stringent warpage control requirements, including 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking, meeting the needs of high-precision advanced packaging processes.

[0011] For example, the material of the glass substrate may be borosilicate or boroaluminosilicate, etc.

[0012] It should be noted that the abbreviation for bow curvature is Bow.

[0013] It should be noted that "at least one side" means that a stress layer can be formed on one side of the glass substrate, or on both sides of the glass substrate.

[0014] Preferably, the stress layer is located on both sides of the glass substrate, and the compressive stresses are different.

[0015] Preferably, the manufacturing method includes the following steps: We provide glass substrates.

[0016] The glass substrate is polished and then heated to T. p The pre-bent shape is formed by hot pressing on a molding die with a target curvature and then cooled; where T p =T g +∆H,T g The glass transition temperature of the glass substrate is ∆H, which is 30-80℃, for example, it can be 30℃, 40℃, 50℃, 60℃, 70℃ or 80℃, etc.

[0017] At least one surface of the glass carrier plate having the pre-bent shape is chemically strengthened to form a compressive stress layer, thereby obtaining a pre-warped glass carrier plate with the target curvature.

[0018] This invention utilizes a process of "physical shaping as the foundation and chemical strengthening as the application" to construct a dual control mechanism of "pre-deformation-stress compensation." This achieves precise design and thermal stability control of the glass substrate's curvature, fundamentally eliminating dynamic warpage caused by material CTE mismatch. It integrates deformation control and mechanical strengthening, ensuring the long-term stability of the pre-deformation curvature under high-temperature processes while significantly improving the mechanical strength of the glass substrate. This glass substrate is suitable for a full range of advanced packaging scenarios with stringent warpage control requirements, including 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking, meeting the needs of high-precision advanced packaging processes.

[0019] In this invention, chemical strengthening significantly improves the bending and impact resistance of the glass substrate, greatly reducing the breakage rate of ultrathin wafers during the manufacturing process and enhancing production robustness.

[0020] The manufacturing method provided by this invention has precise and flexible deformation control capabilities, provides a wide range of curvature settings and micron-level fine-tuning capabilities, and can obtain precise and controllable uniform bending, meeting the requirements of high-precision advanced packaging processes.

[0021] Preferably, the glass substrate is a wafer or a square plate, and the diameter of the wafer is ≥300mm, for example, it can be 300mm, 350mm or 400mm, etc.

[0022] Preferably, the thickness of the glass carrier plate is 0.5-1.3 mm, for example, it can be 0.5 mm, 1 mm or 1.3 mm.

[0023] Preferably, the curvature of the polished glass substrate satisfies: |X0|≤20μm, for example, it can be 20μm, 15μm, 10μm, 5μm or 1μm, etc.

[0024] Preferably, the hot pressing time is 5-60 minutes, for example, 5 minutes, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

[0025] Preferably, during the cooling process, the cooling rate is <3℃ / min, for example, it can be 2℃ / min, 1.5℃ / min, 1℃ / min or 0.5℃ / min, more preferably <2℃ / min, and even more preferably <1℃ / min.

[0026] This invention uses a physical shaping method of hot pressing and cooling to enable glass substrates to obtain a permanent, thermally stable basic curved shape.

[0027] Preferably, the curvature of the glass carrier plate having the pre-bent shape satisfies: |X1|=10-500μm, for example, it can be 10μm, 50μm, 100μm, 150μm, 200μm, 250μm, 300μm, 350μm, 400μm, 450μm or 500μm, etc.

[0028] Preferably, the chemical strengthening treatment method includes an ion exchange method, the steps of which include: coating a molten salt containing alkali metal ions onto at least one side surface of a glass substrate, and then performing an ion exchange treatment.

[0029] The ion exchange treatment temperature is 300-500℃, for example, 300℃, 400℃ or 500℃, and the holding time is 1-10h, for example, 1h, 3h, 5h, 7h, 9h or 10h; the molten salt contains 30-70% alkali metal ions by mass, for example, 30%, 40%, 50%, 60% or 70%.

[0030] This invention, through chemical strengthening treatment, can, on the one hand, precisely fine-tune the absolute value of the curvature of the glass substrate within the range of 10μm to 500μm to achieve the final target curvature value; on the other hand, it can make the four-point bending strength of the glass substrate reach 1.1 to 5 times that of the original substrate.

[0031] It should be noted that when forming compressive stress layers with different compressive stresses on both sides of the glass carrier plate, this invention can achieve this by controlling the different mass percentages of alkali metal ions in the molten salt on both sides.

[0032] Preferably, the surface compressive stress of the surface compressive stress layer is ≥20MPa, for example, it can be 20MPa, 30MPa, 40MPa, 50MPa, 70MPa or 80MPa, etc., preferably ≥50MPa, and more preferably ≥80MPa.

[0033] Preferably, the depth of the compressive stress layer is 1-100 μm, for example, it can be 1 μm, 5 μm, 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, or 100 μm. It should be noted that the depth of the surface compressive stress layer refers to the depth of ion exchange.

[0034] In this invention, the surface compressive stress of the compressive stress layer obtained by chemical strengthening treatment is ≥20MPa, and the depth is 1-100μm. The compressive stress layer under these parameters is conducive to achieving the required curvature of the product and having sufficient bending strength.

[0035] Preferably, the manufacturing method includes the following steps: We provide glass substrates.

[0036] The glass substrate is polished, then placed on a mold with a preset curvature, and heated to T. p The material undergoes hot bending and then cooling to form a pre-bent shape; among which, T p =T g +∆H,T g The glass transition temperature of the glass substrate is ∆H, which is 50-200℃, for example, it can be 50℃, 100℃, 150℃ or 200℃.

[0037] A compressive stress layer is prepared on at least one side surface of a glass carrier having the pre-bent shape to obtain a pre-warped glass carrier with a target curvature.

[0038] In the manufacturing method provided by this invention, heating to T p It undergoes hot bending treatment, followed by cooling, at this T p At that temperature, because glass is a supercooled liquid, its viscosity is around 10. 9 Pa•s to 10 11 Between Pa and s, deformation can occur, and the glass can achieve the preset mold curvature.

[0039] The manufacturing method provided by this invention can precisely control the curvature of the glass substrate and simultaneously improve the mechanical strength of the glass substrate, providing a high-precision control path for MEMS sensors, optical components and other applications that do not require exposure to extreme high temperatures.

[0040] For example, the mold may be a graphite mold or a ceramic mold, etc.

[0041] Preferably, the glass substrate is a wafer or a square plate, and the diameter of the wafer is ≥300mm, for example, it can be 300mm, 350mm or 400mm, etc.

[0042] Preferably, the thickness of the glass carrier plate is 0.5-1.3 mm, for example, it can be 0.5 mm, 1 mm or 1.3 mm.

[0043] Preferably, the curvature of the polished glass substrate satisfies: |X0|≤20μm, for example, it can be 0.5mm, 1mm or 1.3mm, etc.

[0044] Preferably, the heating to T p During the process, the heating rate is <3℃ / min, for example, it can be 2℃ / min, 1.5℃ / min, 1℃ / min or 0.5℃ / min, preferably <2℃ / min, and more preferably ≤1℃ / min.

[0045] Preferably, the heat preservation time for the hot bending treatment is 10-60 minutes, for example, it can be 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

[0046] Preferably, during the cooling process, the cooling rate is 0.5-5℃ / min, for example, it can be 0.5℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min, etc.

[0047] The present invention employs the above-mentioned heating method in conjunction with the above-mentioned slow cooling method, which can effectively avoid defects such as cracking of glass during rapid cooling.

[0048] Preferably, the method for preparing the compressive stress layer is selected from any of the following: (a) Chemical method: A salt solution containing alkali metal ions is coated onto at least one side of a glass substrate for ion exchange treatment to form a compressive stress layer.

[0049] The concentration of alkali metal ions in the salt solution is 10-90 wt%, for example, it can be 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, or 90 wt%. The temperature of the ion exchange treatment is 360-500℃, for example, it can be 360℃, 400℃, 450℃, or 500℃. The holding time is 0.5-16h, for example, it can be 0.5h, 1h, 3h, 5h, 8h, 10h, 13h, or 16h.

[0050] (b) Physical method: A functional thin film is deposited on at least one side surface of a glass substrate using physical vapor deposition; wherein the functional thin film includes a silicon dioxide thin film and / or a silicon nitride thin film.

[0051] In preparing the compressive stress layer, this invention utilizes a chemical method based on a salt solution containing alkali metal ions. This method allows lithium ions and / or sodium ions in the glass to exchange with alkali metal ions (such as sodium ions and / or potassium ions) in the salt solution at high temperatures. Since the ionic radius in the salt solution is larger than that of the alkali metal ions in the glass, surface compressive stress is formed after the ions are replaced on the glass surface. As for the physical method, physical vapor deposition is used to take advantage of the significant mismatch in the thermal expansion coefficients between the glass substrate and the functional thin film, thereby generating stress at the interface between the two materials and ultimately achieving physical control of the film curvature.

[0052] It should be noted that when the salt solution is coated on both sides of the glass substrate, the coating thickness can be the same or different.

[0053] Secondly, the present invention provides a pre-warped glass carrier plate, which is obtained by the manufacturing method described above.

[0054] After undergoing subsequent heat treatment, the pre-warped glass substrate exhibits a curvature change rate of less than 5%, for example, it can be 4%, 3%, 2% or 1%, etc.

[0055] The pre-warped glass substrate has a four-point bending strength ≥120MPa, for example, it can be 120MPa, 140MPa or 160MPa, etc.

[0056] For example, the heat treatment can be performed at 400°C for 1 hour.

[0057] Thirdly, the present invention provides a pre-warped glass carrier plate, which is obtained by the manufacturing method described above.

[0058] Fourthly, the present invention provides an application of the pre-warped glass substrate as described in the second aspect in 2.5D chip packaging, 3D integrated circuit packaging, 3D fan-out packaging, SiP system-in-package or wafer-level chip stacking packaging.

[0059] Fifthly, the present invention provides an application of the pre-warped glass substrate as described in the third aspect in the fabrication of MEMS sensors or semiconductor packaging structures.

[0060] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0061] Compared with the prior art, the present invention has the following beneficial effects: This invention utilizes a process of "physical shaping as the foundation and chemical strengthening as the application" to construct a dual control mechanism of "pre-deformation-stress compensation." This achieves precise design and thermal stability control of the glass substrate's curvature, fundamentally eliminating macroscopic warpage caused by material CTE mismatch. It integrates deformation control and mechanical strengthening, ensuring the long-term stability of the pre-deformation curvature under high-temperature processes while significantly improving the mechanical strength of the glass substrate. This glass substrate is suitable for a full range of advanced packaging scenarios with stringent warpage control requirements, including 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking, meeting the needs of high-precision advanced packaging processes. Attached Figure Description

[0062] Figure 1 This is a schematic diagram illustrating the definition of Bow in this invention.

[0063] Figure 2 This is a partial process flow diagram provided in Embodiment 2 of the present invention.

[0064] Figure 3 This is a schematic diagram illustrating the principle of how the stress layer affects the curvature in this invention.

[0065] Figure 4 This is a warping evolution diagram of the pre-warped glass substrate provided in Embodiment 1 of the present invention during a simulated packaging thermal process.

[0066] Figure 5 This is a warpage evolution diagram of the glass substrate provided in Comparative Example 1 of the present invention during a simulated packaging thermal process.

[0067] Among them, 1-glass substrate; 2-graphite mold; 3-potassium nitrate precursor thin layer. Detailed Implementation

[0068] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0069] The scope of this invention can be defined by lower and upper limits. The selected lower and upper limits define the boundaries of a specific range. The range defined in this way can be defined by the inclusion or exclusion of endpoints. Any endpoint can be independently selected for inclusion or exclusion, and all lower and upper limits can be arbitrarily combined to form new ranges. That is, any lower limit can be combined with any upper limit to form an effective range. For example, if the ranges of 60~120 and 80~110 are listed for specific parameters, it should be understood that the ranges of 60~110 and 80~120 also fall within the scope of this invention. In addition, if the minimum range values ​​1 and 2 are listed, and the maximum range values ​​3, 4 and 5 are also listed, then all ranges of 1~3, 1~4, 1~5, 2~3, 2~4 and 2~5 fall within the scope of this invention. In this invention, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0~5" means that all real numbers between 0 and 5 have been fully listed in this document, and "0~5" is only a shortened representation of this set of numerical combinations. When a parameter is expressed as an integer ≥2, it is equivalent to listing positive integers that meet the requirements, such as 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. When a parameter is expressed as an integer selected from "2~10", it is equivalent to listing any integer among 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0070] In this invention, "a combination of at least two" refers to a quantity greater than or equal to 2 unless otherwise specified. For example, "any one or a combination of at least two" means that any one of the listed items can be selected, or a combination of at least two of the listed items formed in a manner that does not conflict and enables the implementation of this invention. In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" cover any one of two or more related listed items, as well as any and all combinations of the related listed items. The arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" means a set consisting of A, B, and combinations of A and B, where "containing A and / or B" can be understood, depending on the context of the statement, as containing A, containing B, or simultaneously containing both A and B. In this invention, "optional" means that the corresponding feature, component, step or solution is not necessary, that is, it is selected from either "with" or "without". If there are multiple "optional" limitations in a technical solution, unless otherwise specified and there is no technical conflict or mutual constraint, each "optional" limitation is independent and does not affect the others.

[0071] In this invention, technical features or solutions described using open-ended terms such as "comprising" or "including" do not exclude additional non-conflicting elements beyond the listed elements unless otherwise specified. They are considered to disclose both closed-ended features or solutions consisting solely of the listed elements and open-ended features or solutions that may include additional non-conflicting elements beyond the listed elements. For example, if A includes a1, a2, and a3, unless otherwise specified, this means that A can consist only of a1, a2, and a3, or it can include other non-conflicting elements based on a1, a2, and a3. This corresponds to the disclosure of technical solutions such as "A consists of a1, a2, and a3," "A is selected from a1, a2, and a3," and "A not only includes a1, a2, and a3, but may also include other non-conflicting elements." All embodiments and optional embodiments of this invention, unless otherwise specified and without technical conflict, can be combined to form new technical solutions, and such combinations fall within the scope of this invention. The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various locations throughout the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this invention can be combined with other embodiments that do not conflict with the technology. The ordinal numbers "first," "second," "third," and "fourth," etc., used in the expressions "first aspect," "second aspect," "third aspect," and "fourth aspect" in this invention are for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly specifying the importance or quantity of the indicated technical features. They serve only as a non-exhaustive enumeration and do not constitute a closed limitation on quantity.

[0072] In this invention, the order in which the steps are written in the methods described in each embodiment does not imply a strict execution order. The actual execution order of each step should be determined based on its function and possible internal logic. Unless otherwise specified, all steps of this invention can be executed in the order they are written, or in any order without technical conflict. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) executed sequentially, or it may include steps (b) and (a) executed sequentially. If the method also includes step (c), then step (c) can be added to the method in any order without conflict, including but not limited to the execution order of steps (a), (b), and (c), steps (a), (c), and (b), steps (c), (a), and (b), etc.

[0073] Figure 1 A schematic diagram illustrating the definition of Bow in this invention is shown. As can be seen from the diagram, the Bow of the glass substrate 1 is the difference between B1 and B2.

[0074] Figure 3 The diagram illustrates the principle of how the stress layer affects the curvature in this invention. As shown in the diagram, the presence of the stress layer can fine-tune, either enhance or weaken, the curvature of the glass carrier plate 1: when the compressive stress 1 is greater than the compressive stress 2, the curvature of the glass carrier plate 1 will be enhanced, and vice versa.

[0075] Example 1 This embodiment provides a method for manufacturing a pre-warped glass carrier plate, the method comprising the following steps: (1) Provide a glass carrier plate; the glass carrier plate is alkali-containing borosilicate glass, the glass grade is Corning Gorilla Glass 3, and the size is 300mm×300mm×1mm.

[0076] (2) Polish the glass substrate, and the curvature of the glass substrate after polishing satisfies: |X0|=20μm; then heat it to T p The material is hot-pressed for 30 minutes on a graphite mold with the target curvature, and then cooled at a rate of 1.5℃ / min to form a pre-bent shape; where T p =T g +50℃, T g The glass transition temperature of the glass substrate is given; the curvature of the glass substrate with the pre-bent shape satisfies: |X1|=80μm.

[0077] (3) A molten salt with a KNO3 mass percentage of 60% is coated on the convex surface of the glass substrate with a coating thickness of 10 μm. Then, it is placed in a high-temperature furnace at 400°C for 1 hour of ion exchange treatment to form a compressive stress layer with a surface compressive stress of 30 MPa and a depth of 12 μm, thereby obtaining a pre-warped glass substrate with a target curvature of 311 μm.

[0078] A four-point bending strength test was performed on the pre-warped glass carrier plate, and it was found that the four-point bending strength of the pre-warped glass carrier plate was 330 MPa, which is 2.7 times that of the original glass carrier plate (120 MPa).

[0079] The pre-warped glass substrate was heat-treated at 400°C for 1 hour, and the change rate of the Bow value of the pre-warped glass substrate was found to be less than 2%.

[0080] The pre-warped glass substrate provided in this embodiment, in the Fan-Out process that includes multi-layer RDL and chip stacking, fully pre-warped to offset the high warpage caused by CTE mismatch of heterogeneous materials in the chip, effectively reducing the process incompatibility caused by excessive warpage during packaging.

[0081] Example 2 This embodiment provides a method for manufacturing a pre-warped glass carrier plate, the method comprising the following steps: (1) Provide a glass carrier plate; the glass carrier plate is alkali borosilicate glass, the glass grade is Corning Gorilla Glass 3, and the size is 300mm×300mm×1mm.

[0082] (2) Polish the glass substrate so that the curvature of the glass substrate after polishing satisfies: |X0|=20μm; then place it on a graphite mold with a preset curvature and heat it to T at a heating rate of 1℃ / min. p The glass substrate is subjected to a hot bending process for 15 minutes, followed by a cooling rate of 2℃ / min to obtain a pre-bent glass substrate; wherein, T p =T g +100℃, T g The glass transition temperature of the glass substrate is given; the curvature of the glass substrate with the pre-bent shape satisfies: |X1|=80μm.

[0083] (3) A 50wt% KNO3 aqueous solution is coated on the convex surface of the glass substrate to form a potassium nitrate precursor thin layer with a thickness of 10μm. Then, it is placed in a high-temperature furnace at 400℃ for 1h of ion exchange treatment to form a compressive stress layer, thereby obtaining a pre-warped glass substrate with a target curvature of 416μm.

[0084] A four-point bending strength test was performed on the pre-warped glass carrier plate, and it was found that the four-point bending strength of the pre-warped glass carrier plate was 280 MPa, which is 2.3 times that of the original glass carrier plate (120 MPa).

[0085] The pre-warped glass substrate was heat-treated at 400°C for 1 hour, and the change rate of the Bow value of the pre-warped glass substrate was found to be less than 5%.

[0086] Figure 2 A partial process flow diagram of this embodiment is shown. As can be seen from the diagram, the polished glass substrate 1 is placed on a graphite mold 2 with a preset curvature and subjected to hot bending treatment. Then, a KNO3 aqueous solution is coated on the convex surface of the glass substrate 1 to form a potassium nitrate precursor thin layer 3.

[0087] Example 3 The difference between this embodiment and embodiment 2 is that step (3) is replaced by: A 2 μm thick silica film was deposited on the convex surface of a glass substrate using physical vapor deposition to prepare a pre-warped glass substrate with a target curvature of 50 μm.

[0088] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0089] A four-point bending strength test was performed on the pre-warped glass carrier plate, and it was found that the four-point bending strength of the pre-warped glass carrier plate was 150 MPa, which is 1.25 times that of the original glass carrier plate (120 MPa).

[0090] The pre-warped glass substrate was heat-treated at 400°C for 1 hour, and the change rate of the Bow value of the pre-warped glass substrate was found to be less than 5%.

[0091] Example 4 The difference between this embodiment and Embodiment 1 is that T p =T g +100℃.

[0092] The remaining manufacturing methods and parameters are consistent with those in Example 1.

[0093] Example 5 The difference between this embodiment and Embodiment 1 is that the cooling rate is 3°C / min.

[0094] The remaining manufacturing methods and parameters are consistent with those in Example 1.

[0095] Example 6 The difference between this embodiment and Embodiment 1 is that the temperature of the ion exchange treatment is 200°C.

[0096] The remaining manufacturing methods and parameters are consistent with those in Example 1.

[0097] Example 7 The difference between this embodiment and Embodiment 1 is that the temperature of the ion exchange treatment is 600°C.

[0098] The remaining manufacturing methods and parameters are consistent with those in Example 1.

[0099] Example 8 The difference between this embodiment and embodiment 2 is that T p =T g +30℃.

[0100] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0101] Example 9 The difference between this embodiment and embodiment 2 is that T p =T g +250℃.

[0102] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0103] Example 10 The difference between this embodiment and Embodiment 2 is that the cooling rate during the cooling process is 8°C / min.

[0104] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0105] Example 11 The difference between this embodiment and Embodiment 2 is that the temperature of the ion exchange treatment is 300°C.

[0106] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0107] Example 12 The difference between this embodiment and Embodiment 2 is that the temperature of the ion exchange treatment is 550°C.

[0108] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0109] Comparative Example 1 This comparative example provides a glass carrier plate as described in step (1) of Example 1.

[0110] Figure 4 and Figure 5 The figures show the warpage evolution of the pre-warped glass substrate provided in Example 1 and the glass substrate provided in Comparative Example 1 during a simulated packaging thermal process. The comparison shows that if the glass substrate is not pre-bowing, significant upward warping will occur at the substrate edges during advanced packaging due to thermal mismatch stress between the layers. This will not only severely affect the etching accuracy of the RDL wiring but may also trigger a warpage over-limit alarm in the semiconductor processing equipment. Comparative Example 2 The difference between this comparative example and Example 1 is that hot pressing is not performed.

[0111] The remaining manufacturing methods and parameters are consistent with those in Example 1.

[0112] The pre-warped glass substrate prepared in this comparative example, after undergoing a simulated RDL process heat treatment at 350℃, exhibited a warping of approximately 1mm due to the large composite equivalent coefficient of thermal expansion (CTE) generated by multiple materials such as copper RDL, solder, epoxy molding compound (EMC), and chip, which differed significantly from the CTE of the glass substrate itself. This indicates that its warping compensation function has essentially failed.

[0113] Comparative Example 3 The difference between this comparative example and Example 2 is that hot pressing is not performed.

[0114] The remaining manufacturing methods and parameters are consistent with those in Example 2.

[0115] Performance testing The glass substrates obtained in the above embodiments and comparative examples were subjected to a four-point bending strength test, and the test method was based on ASTM C158: Standard Test Method for Bending Strength of Glass.

[0116] The test results are shown in Table 1.

[0117] Table 1 analyze: As shown in Table 1, this invention, through a process of "physical shaping as the foundation and chemical strengthening as the application," constructs a dual control mechanism of "pre-deformation-stress compensation," achieving precise design and thermal stability control of the glass substrate's curvature. This fundamentally eliminates the macroscopic warpage problem caused by material CTE mismatch, realizing the functional integration of deformation control and mechanical strengthening. It ensures the long-term stability of the pre-deformation curvature under high-temperature processes while significantly improving the mechanical strength of the glass substrate. This glass substrate is suitable for a full range of advanced packaging scenarios with stringent warpage control requirements, including 2.5D / 3D ICs, Fan-Out, SiP, and chip stacking, meeting the needs of high-precision advanced packaging processes.

[0118] A comparison between Example 1 and Example 4 shows that if heated to T... p If the temperature after heating is too high, the bending strength will decrease.

[0119] A comparison of Example 1 and Example 5 shows that if the cooling rate is too high, the bending strength of the glass will decrease.

[0120] As can be seen from the comparison between Example 1 and Examples 6-7, if the temperature of ion exchange treatment is too low, the chemical strengthening of glass cannot be effectively achieved; if the temperature of ion exchange treatment is too high, the glass will have a relaxation effect after ion exchange, causing the chemical strengthening effect caused by ion exchange to fail.

[0121] A comparison of Example 2 and Examples 8-9 shows that if heated to T... p If the temperature after heating is too low, the glass cannot be pre-bent; if it is heated to T... p If the temperature is too high after heating, the glass is prone to cracking.

[0122] As can be seen from the comparison between Example 2 and Example 10, if the cooling rate is too high during the cooling process, the glass is prone to cracking.

[0123] As can be seen from the comparison between Example 2 and Examples 11-12, if the temperature of ion exchange treatment is too low, the chemical strengthening effect is weak; if the temperature of ion exchange treatment is too high, the chemical strengthening effect will be destroyed by high-temperature ion relaxation and microcracks will be generated on the glass surface, thus failing to achieve strength improvement.

[0124] As can be seen from the comparison between Example 1 and Comparative Example 1, if the glass substrate is not pre-warped, the glass and other materials in the glass substrate will be bent during the advanced packaging process.

[0125] As can be seen from the comparison between Example 1 and Comparative Example 2, if hot pressing is not performed, the resulting glass substrate will warp by about 1 mm after being subjected to a simulated RDL process heat treatment at 350°C, indicating that the warp compensation function is basically ineffective.

[0126] As can be seen from the comparison between Example 2 and Comparative Example 3, if hot pressing is not performed, the resulting glass substrate will warp by about 1 mm after undergoing heat treatment of the simulated RDL process at 350°C, indicating that the warp compensation function is basically ineffective.

[0127] It should be noted that the present invention is illustrated through the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for manufacturing a pre-warped glass carrier plate, characterized in that, The manufacturing method includes the following steps: Provide glass carrier plates; The glass substrate is thermoformed to form a pre-bent shape; A stress layer is formed on at least one side surface of a glass carrier having the pre-bent shape to adjust the curvature of the glass carrier, thereby obtaining a pre-warped glass carrier with a target curvature.

2. The manufacturing method according to claim 1, characterized in that, The manufacturing method includes the following steps: Provide glass carrier plates; The glass substrate is polished and then heated to T. p The pre-bent shape is formed by hot pressing on a molding die with a target curvature and then cooled; where T p =T g +∆H,T g The glass transition temperature of the glass substrate is ∆H, which is 30-80℃. At least one surface of the glass carrier plate having the pre-bent shape is chemically strengthened to form a compressive stress layer, thereby obtaining a pre-warped glass carrier plate with the target curvature.

3. The manufacturing method according to claim 2, characterized in that, The glass substrate is a wafer or a square plate, and the diameter of the wafer is ≥300mm; And / or, the thickness of the glass substrate is 0.5-1.3 mm; And / or, the curvature of the polished glass substrate satisfies: |X0|≤20μm; And / or, the hot pressing time is 5-60 min. And / or, during the cooling process, the cooling rate is <3℃ / min, preferably <2℃ / min, and more preferably <1℃ / min.

4. The manufacturing method according to claim 3, characterized in that, The curvature of the glass carrier plate with the pre-bent shape satisfies: |X1|=10-500μm; And / or, the chemical strengthening treatment method includes ion exchange, the steps of which include: coating a molten salt containing alkali metal ions onto at least one side surface of a glass substrate, and then performing ion exchange treatment; The ion exchange treatment is performed at a temperature of 300-500℃ for 1-10 hours; the molten salt contains 30-70% alkali metal ions by mass. And / or, the surface compressive stress of the compressive stress layer is ≥20MPa, preferably ≥50MPa, and more preferably ≥80MPa; And / or, the depth of the compressive stress layer is 1-100 μm.

5. The manufacturing method according to claim 1, characterized in that, The manufacturing method includes the following steps: Provide glass carrier plates; The glass substrate is polished, then placed on a mold with a preset curvature, and heated to T. p The material undergoes hot bending and then cooling to form a pre-bent shape; among which, T p =T g +∆H,T g The glass transition temperature of the glass substrate is ∆H, which is 50-200℃. A compressive stress layer is prepared on at least one side surface of a glass carrier having the pre-bent shape to obtain a pre-warped glass carrier with a target curvature.

6. The manufacturing method according to claim 5, characterized in that, The glass substrate is a wafer or a square plate, and the diameter of the wafer is ≥300mm; And / or, the thickness of the glass substrate is 0.5-1.3 mm; And / or, the curvature of the polished glass substrate satisfies: |X0|≤20μm; And / or, the heating to T p During the process, the heating rate is <3℃ / min, preferably <2℃ / min, and more preferably ≤1℃ / min; And / or, the heat preservation time for the hot bending treatment is 10-60 min; And / or, during the cooling process, the cooling rate is 0.5-5℃ / min; And / or, the method for preparing the compressive stress layer is selected from any of the following: (a) Chemical method: A salt solution containing alkali metal ions is coated onto at least one side of a glass substrate for ion exchange treatment to form a compressive stress layer; The concentration of alkali metal ions in the salt solution is 10-90 wt%; the temperature of the ion exchange treatment is 360-500℃, and the holding time is 0.5-16 h. (b) Physical method: A functional thin film is deposited on at least one side surface of a glass substrate using physical vapor deposition; wherein the functional thin film includes a silicon dioxide thin film and / or a silicon nitride thin film.

7. A pre-warped glass carrier plate, characterized in that, The pre-warped glass substrate is obtained by the manufacturing method described in any one of claims 2-4; The pre-warped glass substrate undergoes a curvature change rate of less than 5% after subsequent heat treatment; The four-point bending strength of the pre-warped glass substrate is ≥120MPa.

8. A pre-warped glass carrier plate, characterized in that, The pre-warped glass substrate is obtained using the manufacturing method described in claim 5 or 6.

9. The application of a pre-warped glass substrate as described in claim 7 in 2.5D chip packaging, 3D integrated circuit packaging, 3D fan-out packaging, SiP system-in-package or wafer-level chip stacking packaging.

10. The application of the pre-warped glass substrate as described in claim 8 in the fabrication of MEMS sensors or semiconductor packaging structures.

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