A bgv structure for enhancing the bonding force of glass-based electroplated copper and a method of manufacturing the same

Abstract

The application discloses a BGV structure for enhancing the bonding force of glass-based electroplated copper and a manufacturing method thereof, and applies to the technical field of packaging. The technical scheme is as follows: a BGV structure for enhancing the bonding force of glass-based electroplated copper, comprising a glass Core layer, an RDL redistribution layer, a Core conductive structure and a layer-increasing unit, wherein the layer-increasing unit comprises, from inside to outside, an interlayer dielectric layer, a layer-increasing glass layer, a layer-increasing metal pattern layer and a layer-increasing metal conductive part; the layer-increasing metal conductive part comprises a layer-increasing BGV hole copper filled in the layer-increasing BGV hole, an anchoring copper part filled in a side excavation part and a connecting copper part filled in a dielectric layer conductive hole, and the anchoring copper part forms a mechanical anchoring structure for limiting the layer-increasing BGV hole copper from being separated at one end of the layer-increasing BGV hole close to the interlayer dielectric layer. The BGV structure has the technical effect of improving the bonding strength between the hole copper and the glass-based laminated interface, providing a buffer space for subsequent thermal stress release and improving reliability.

Description

Technical Field

[0001] This invention relates to the field of packaging technology, and in particular to a BGV structure for enhancing the adhesion of electroplated copper to a glass substrate and its manufacturing method. Background Technology

[0002] With the development of advanced packaging, glass-based PCBs and high-density 3D interconnect technology, glass materials are gradually being used in fields such as radio frequency devices, MEMS packaging and high-performance computing packaging due to their advantages such as low dielectric loss, adjustable coefficient of thermal expansion (CTE), low radio frequency loss and linearity, and high dimensional stability.

[0003] In glass-based substrates or glass-based PCBs, glass cores, RDL redistribution layers, and add-on glass are typically stacked layer by layer to achieve higher wiring density and thicker packaging substrates. However, due to the smooth surface and low chemical reactivity of glass, the bonding between the copper layer or filler via and the glass via wall mainly relies on seed layers, adhesive layers, or interface contacts. After annealing, thermal cycling, humid environments, or subsequent packaging processes, stress concentration can easily occur near the bottom interface of the copper via due to the differences in thermal expansion properties between the copper via, glass, and interlayer dielectric materials. This can lead to microcracks, warping, or peeling between the copper via and the via wall or bottom, thereby reducing the reliability of the connection. Therefore, it is necessary to improve the existing glass-based laminate structure to enhance the bonding strength between the copper via and the glass-based laminate interface and provide buffer space for subsequent thermal stress release, thus improving reliability. Summary of the Invention

[0004] The primary objective of this invention is to provide a BGV structure that enhances the bonding strength of copper plating on a glass substrate. Its advantages include improving the bonding strength between the copper via and the glass substrate laminate interface, providing a buffer space for subsequent thermal stress release, and improving reliability.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a BGV structure for enhancing the adhesion of electroplated copper on a glass substrate, comprising: A glass core layer has a first surface and a second surface disposed opposite to each other, and an RDL redistribution layer is provided on both the first surface side and the second surface side of the glass core layer; The core conduction structure extends along the thickness direction of the glass core layer and is electrically connected to the RDL redistribution layer; The layering unit is provided in at least one set, which are respectively disposed on the first surface side and / or the second surface side of the glass core layer, including an interlayer dielectric layer, a layered glass layer, a layered metal pattern layer and a layered metal conductive part arranged sequentially from the inside to the outside. The added metal conductive portion includes an added BGV hole formed in the added glass layer and a dielectric layer through hole formed in the interlayer dielectric layer and connected to the added BGV hole. The added BGV hole has a side cutout at one end near the interlayer dielectric layer. The side cutout extends laterally along the periphery of the bottom of the added BGV hole relative to the hole body. The added metal conductive portion includes added BGV hole copper filled in the added BGV hole, anchoring copper portion filled in the side cut portion, and connecting copper portion filled in the dielectric layer conductive hole. The anchoring copper portion forms a mechanical anchoring structure at one end of the added BGV hole near the interlayer dielectric layer to restrict the added BGV hole copper from detaching.

[0006] The present invention is further configured such that: the side cutouts are continuously distributed or at least partially distributed around the bottom periphery of the BGV hole, and the anchoring copper part is filled in the side cutouts in an annular hanging wall shape.

[0007] The present invention is further configured such that: the bottom CD of the BGV hole on the side near the interlayer dielectric layer is 0.8-2 times the top CD on the side away from the interlayer dielectric layer; and the size of the dielectric layer via on the side near the BGV hole is smaller than the minimum aperture of the BGV hole along the thickness direction of the BGV hole in the layer.

[0008] The present invention is further configured such that: the interlayer dielectric layer is an ABF layer, the thickness of the glass core layer and the add-on glass layer is between 100-400 μm, and the thickness of the interlayer dielectric layer is between 20-60 μm.

[0009] The present invention is further configured such that: the Core conduction structure is a TGV via copper filled in the TGV via penetrating the glass Core layer, and the TGV via copper penetrates the first surface and the second surface of the glass Core layer.

[0010] The present invention is further configured such that: the Core conduction structure is a BGV via copper filled in the BGV blind via of the glass Core layer, one end of the BGV via copper is exposed on the first surface of the glass Core layer, and after thinning on the second surface side of the glass Core layer, the other end of the BGV via copper is exposed on the second surface of the glass Core layer, and the bottom CD of the BGV via copper on the second surface is greater than 20 μm.

[0011] The second objective of this invention is to provide a method for manufacturing a BGV structure that enhances the bonding strength between copper plating on a glass substrate. Its advantages include improving the bonding strength between the copper via and the glass substrate laminate interface, providing a buffer space for subsequent thermal stress release, and improving reliability.

[0012] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a method for manufacturing a BGV structure that enhances the adhesion of electroplated copper to a glass substrate, comprising: Step 1: Fabricate the glass core layer and the core conductive structure; Step 2: Sequentially press the interlayer dielectric layer and the add-on glass layer onto the first surface side and / or the second surface side of the glass core layer; Step 3: Laser modification is performed on the build-up glass layer to form an area to be etched and modified within the build-up glass layer. Then, wet etching is performed on the laser-modified build-up glass layer to form a build-up BGV hole extending towards the interlayer dielectric layer. When the etching front reaches the interface between the build-up glass layer and the interlayer dielectric layer, the etching solution extends laterally from the bottom interface edge region of the build-up BGV hole and performs lateral etching on the bottom edge region of the build-up glass layer near the interlayer dielectric layer to form a side hollow that extends laterally relative to the body of the build-up BGV hole. Step 4: Perform via drilling on the interlayer dielectric layer to form a dielectric layer via connecting the BGV via and the RDL redistribution layer; Step 5: Form augmented metal conductive portions in the augmented BGV holes, the side cutouts, and the dielectric layer vias; then form an augmented metal patterned layer electrically connected to the augmented metal conductive portions on the side of the augmented glass layer away from the interlayer dielectric layer. Step 6: Repeat steps 2-5 to form at least one layer of the added-layer unit on at least one side of the glass core layer.

[0013] The present invention is further configured such that step 1 includes: Step 1.1: Perform laser modification on the glass core layer. During the laser modification process, the laser focus is set at a position close to 1 / 2 of the thickness of the glass core layer, and a TGV via is formed through the glass core layer by wet etching. Step 1.2: Deposit a seed layer in the TGV via and electroplate copper to fill it to form TGV via copper; Step 1.3: Perform double-sided CMP treatment on the glass core layer; Step 1.4: Prepare RDL redistribution layers on the first and second surfaces of the glass Core layer using a semi-additive method.

[0014] The present invention is further configured such that step 1 includes: Step 1.1: Perform laser modification on the glass core layer. During the laser modification process, the laser focus is set close to the upper surface of the glass core layer so that the laser modification area does not extend to the lower surface of the glass core layer. Step 1.2: Perform wet etching on the laser-modified glass core layer to form BGV blind vias; Step 1.3: Deposit a seed layer in the BGV blind via and electroplate copper to fill it to form BGV via copper. Then, perform CMP treatment on the upper surface of the glass core layer to remove the surface copper. Step 1.4: Thin the bottom surface of the glass core layer and perform CMP treatment to expose the bottom of the BGV via copper on the bottom surface of the glass core layer, so as to form a core conduction structure. Step 1.5: Prepare RDL redistribution layers on the first and second surfaces of the glass Core layer using a semi-additive method.

[0015] The present invention is further configured such that: in step 2, the pressing pressure between the interlayer dielectric layer and the superimposed glass layer is between 0.1-1 MPa, the pressing time is 100 s, and the pressing temperature is 90°C; In steps 1 and 3, wet etching uses HF etching solution or NaOH etching solution; In step 4, a CO2 laser is used to create openings in the interlayer dielectric layer.

[0016] In summary, the present invention has the following beneficial effects: 1. This invention provides a side cutout in the bottom edge region of the hole near the interlayer dielectric layer of the BGV layer, and forms an anchoring copper part after copper plating. The anchoring copper part forms a mechanical anchoring structure at one end of the BGV hole near the interlayer dielectric layer to prevent the copper in the BGV hole from detaching. This improves the bonding strength between the copper in the hole and the glass substrate laminate interface, thereby reducing the risk of microcracks, warping or peeling between the copper in the hole and the hole wall or bottom, and improving the reliability of the structure. 2. The present invention provides a side cutout at the periphery of the bottom of the BGV hole near the interlayer dielectric layer, thereby providing a buffer space when there is a thermal expansion difference between the copper, glass and interlayer dielectric layers in the BGV hole, reducing the possibility of microcracks at the interface under annealing, thermal cycling and humid heat environments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of Example 1; Figure 2 This is a schematic diagram of the overall structure of Example 2; Figure 3 This is a schematic diagram of steps 1-2 in Example 4; Figure 4 This is a schematic diagram of steps 3-5 in Example 4.

[0018] Reference numerals: 1. Glass Core layer; 2. RDL redistribution layer; 3. Core conductive structure; 31. TGV via copper; 32. BGV via copper; 4. Add-on unit; 5. Interlayer dielectric layer; 6. Add-on glass layer; 7. Add-on metal pattern layer; 8. Add-on metal conductive part; 81. Add-on BGV via; 82. Dielectric layer via; 83. Side cut; 84. Add-on BGV via copper; 85. Anchor copper part; 86. Connecting copper part. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings.

[0020] Example 1: refer to Figure 1 A BGV structure for enhancing the adhesion of copper plating on a glass substrate includes a glass core layer 1, an RDL redistribution layer 2, a core conduction structure 3, and at least one set of add-layer units 4. The glass core layer 1 has a first surface and a second surface disposed opposite to each other. The thickness of the glass core layer 1 is between 100-400μm. The material used is borosilicate glass or low CTE quartz glass. Alternatively, BF33 glass or other glass materials suitable for laser modification and wet drilling can be used. The RDL redistribution layer 2 is provided on both the first surface side and the second surface side of the glass core layer 1.

[0021] The Core conduction structure 3 extends along the thickness direction of the glass Core layer 1 and is electrically connected to the RDL redistribution layer 2. The glass Core layer 1 achieves electrical interconnection along the vertical thickness direction through the Core conduction structure 3, and achieves signal or electrical connection in the horizontal direction through the RDL redistribution layer 2.

[0022] At least one layer-up unit 4 is provided on the first surface side and / or the second surface side of the glass core layer 1. The layer-up unit 4 includes an interlayer dielectric layer 5, a layer-up glass layer 6, a layer-up metal pattern layer 7, and a layer-up metal conductive portion 8 arranged sequentially from the inside to the outside. The layer-up metal conductive portion 8 is disposed within the interlayer dielectric layer 5 and the layer-up glass layer 6, and is electrically connected to the RDL redistribution layer 2. When multiple layer-up units 4 are provided, the multiple layer-up units 4 are stacked sequentially along the direction away from the glass core layer 1, and adjacent layer-up units 4 are electrically connected to each other through the layer-up metal conductive portion 8. The layer-up metal pattern layer 7 is electrically connected to the layer-up metal conductive portion 8 and is used to form one or more of the following: the layer-up RDL redistribution layer 2, a connection pad, or a connection pad for a bump point. In this embodiment, the interlayer dielectric layer 5 is an ABF layer, the thickness of the build-up glass layer 6 is between 100-400 μm, and the thickness of the interlayer dielectric layer 5 is between 20-60 μm. While serving as interlayer insulation and bonding, the interlayer dielectric layer 5 also acts as a boundary limiting layer for the lateral etching of the bottom of the hole when the subsequent wet etching is used to form the build-up BGV via, so as to prevent the wet etching from penetrating the interlayer dielectric layer 5.

[0023] The added metal conductive portion 8 includes an added BGV hole 81 formed in the added glass layer 6 and a dielectric layer through hole 82 formed in the interlayer dielectric layer 5 and communicating with the added BGV hole 81. The added BGV hole 81 extends from the side of the added glass layer 6 away from the interlayer dielectric layer 5 to the side close to the interlayer dielectric layer 5. A side cutout 83 is provided at the end of the added BGV hole 81 close to the interlayer dielectric layer 5. The side cutout 83 extends laterally along the periphery of the bottom of the added BGV hole 81 relative to the hole body of the added BGV hole 81. The added metal conductive portion 8 also includes filling the added BGV hole 81. The addition of BGV via copper 84, anchoring copper portion 85 filled in side cutout 83, and connecting copper portion 86 filled in dielectric layer through-hole 82, with the anchoring portion filled in the side cutout 83 which extends laterally relative to the addition of BGV via 81, so that the anchoring copper portion 85 forms a mechanical anchoring structure at the end of the addition of BGV via 81 near the interlayer dielectric layer 5 to restrict the detachment of the addition of BGV via copper 84, thereby improving the bonding strength between the via copper and the glass substrate laminate interface, thereby reducing the risk of microcracks, warping or peeling between the via copper and the via wall or via bottom, and improving the reliability of the structure.

[0024] Specifically, the side cutouts 83 are continuously distributed around the bottom periphery of the BGV via 81, and the anchoring copper portions 85 are filled in the side cutouts 83 in an annular, wall-hanging manner. The anchoring copper portions 85 are connected to the BGV via copper 84 to form a metal anchoring portion at the bottom of the BGV via, resembling the bottom edge of a volcano or an inverted edge, thereby improving the bonding strength between the via copper and the glass substrate laminate interface. Similarly, the side cutouts 83 are at least partially distributed around the bottom periphery of the BGV via 81. As long as a space that extends laterally relative to the BGV via 81 can be formed at the bottom of the via, and the anchoring copper portions 85 are formed after filling with copper to restrict the peeling of the BGV via copper 84, the bonding strength between the via copper and the glass substrate laminate interface can be enhanced, reducing the risk of microcracks, warping, or peeling. In this embodiment, the side cutouts 83 are mainly used to form the bottom edge region of the BGV via 6 near the interlayer dielectric layer 5, and are not formed by large-area etching of the interlayer dielectric layer 5. The interlayer dielectric layer 5 is mainly used to define the interface boundary and provide interlayer insulation. When ABF is used for the interlayer dielectric layer 5, the etching solution may have a local effect on the inorganic filler or interface surface in the ABF layer, but the main body of the side cutout 83 is still the lateral etching space at the bottom edge of the added glass layer 6.

[0025] Specifically, the bottom CD (bottom opening diameter) of the BGV via 81 near the interlayer dielectric layer 5 is 0.8-2 times the top CD (top opening diameter) away from the interlayer dielectric layer 5. The size of the dielectric layer via 82 near the BGV via 81 is smaller than the minimum aperture of the BGV via 81 along the thickness direction of the BGV via 81. When wet etching is performed using HF etchant, the maximum bottom opening of the BGV via 81 is close to 1 times the top opening diameter of the BGV via 81. When wet etching is performed using NaOH etchant, the maximum bottom opening of the BGV via 81 is close to 2 times the top opening diameter of the BGV via 81. Meanwhile, the side cavity has a side cavity height H along the thickness direction of the added glass layer 6 and a unilateral lateral expansion amount W that extends outward relative to the hole body along the radial direction of the added BGV hole 81. Since wet etching has isotropic etching characteristics for glass materials, the unilateral lateral expansion amount W is close to the side cavity height H, and the ratio of W to H can be between 0.8:1-1.2-1, so that the side cavity 83 has a relatively stable crater-shaped or inverted cross section.

[0026] Specifically, the Core conduction structure 3 is a TGV via copper 31 filled in the TGV via penetrating the glass Core layer 1. The TGV via copper 31 penetrates the first and second surfaces of the glass Core layer 1, so that the dielectric layer via 82 will not be excessively enlarged and thus destroy the limiting effect of the side cutout 83 on the anchor copper part 85, while also enabling the anchor copper part 85 to be stably connected with the lower metal pattern layer.

[0027] Example 2: refer to Figure 2 Compared to Example 1, in this example, the Core conduction structure 3 is a BGV via copper 32 filled in the BGV blind via of the glass Core layer 1. One end of the BGV via copper 32 is exposed on the first surface of the glass Core layer 1. After thinning on the second surface side of the glass Core layer 1, the other end of the BGV via copper 32 is exposed on the second surface of the glass Core layer 1. The bottom CD of the BGV via copper 32 on the second surface is >20μm.

[0028] Example 3: refer to Figure 1 and Figure 2 Compared to embodiments 1 and 2, in this embodiment, multiple layering units 4 are provided on both the first and second surface sides of the glass Core layer 1.

[0029] Each add-in unit 4 includes an interlayer dielectric layer 5, an add-in glass layer 6, an add-in metal pattern layer 7, and an add-in metal conductive section 8 arranged sequentially from the inside out. Adjacent add-in units 4 are electrically connected through corresponding add-in metal conductive structures. At least one add-in glass layer 6 in the add-in unit 4 has a BGV blind hole and a side-hole area at the bottom of the hole. The anchoring copper part 85 of the add-in metal conductive structure is filled in the side-hole area 83.

[0030] Example 4: refer to Figure 3 and Figure 4 A method for manufacturing a BGV structure with enhanced adhesion to electroplated copper on a glass substrate, for manufacturing a BGV structure as shown in Example 1, comprising: Step 1: Prepare glass core layer 1 and core conductive structure 3; Step 1.1: Perform laser modification on the glass core layer 1. During the laser modification process, the laser focus is set at a position close to 1 / 2 of the thickness of the glass core layer 1, and a TGV via is formed through the glass core layer 1 by wet etching. Step 1.2: Deposit a seed layer in the TGV via and fill it with electroplated copper to form TGV via copper 31. The seed layer can be a Ti / Cu combination or a chemical plating method. Step 1.3: Perform double-sided CMP treatment on the glass core layer 1. The CMP treatment removes excess copper from the surface of the glass core layer 1 and exposes the two ends of the TGV hole copper 31 on the first and second surfaces of the glass core layer 1, respectively. Step 1.4: Prepare RDL redistribution layer 2 on the first and second surfaces of glass Core layer 1 using a semi-additive method. RDL redistribution layer 2 is prepared using a semi-additive method, a subtractive method, or other metal patterning processes suitable for packaging substrates. Step 2: Sequentially press the interlayer dielectric layer 5 and the uplift glass layer 6 onto the first surface side and / or the second surface side of the glass core layer 1; Step 3: Laser modification is performed on the additive glass layer 6 to form an area to be etched and modified within the additive glass layer 6. Then, wet etching is performed on the laser-modified additive glass layer 6 to form an additive BGV hole 81 extending towards the interlayer dielectric layer 5 in the additive glass layer 6. When the etching front reaches the interface between the additive glass layer 6 and the interlayer dielectric layer 5, the etching solution extends laterally from the bottom interface edge region of the additive BGV hole 81 and performs lateral etching on the bottom edge region of the additive glass layer 6 near the interlayer dielectric layer 5 to form a side cutout 83 that extends laterally relative to the hole body of the additive BGV hole 81. Step 4: Perform via processing on the interlayer dielectric layer 5 to form a dielectric layer via 82 connecting the add-on BGV via 81 and the RDL redistribution layer 2; Step 5: Form the augmented metal conductive portion 8 in the augmented BGV hole 81, the side cut portion 83 and the dielectric layer through hole 82, and then form the augmented metal patterned layer 7 electrically connected to the augmented metal conductive portion 8 on the side of the augmented glass layer 6 away from the interlayer dielectric layer 5. Specifically, in steps 1 and 3, wet etching uses either HF or NaOH etching solution. Hydrofluoric acid (HF) is currently the dominant wet etching reagent in industrial mass production and is suitable for borosilicate glass (such as Corning Eagle XG and Schott AF32). Sodium hydroxide (NaOH) can theoretically be used for soda-lime glass. When using HF etching solution, the concentration of HF etching solution is between 40% and 50%, and the etching temperature is between 20 and 45°C. During the etching process, 40 kHz ultrasound and 5 rpm rotation are used to promote the renewal of the etching solution in the hole and reduce the retention of reaction products or bubbles in the hole. When using HF etching solution, the aperture angle of the TGV via wall is between 85-87°. If using NaOH solution, the aperture angle of the TGV via wall wall is between 86-89°. In step 1, a picosecond or femtosecond laser is used. Picosecond lasers have a pulse width between 1 and 10 ps, ​​suitable for mass production; femtosecond lasers have a pulse width less than 350 fs, suitable for high-precision or small-sized aperture processing. The laser wavelength can be 1030 nm, 5151 nm, or 343 nm. 1030 nm is the industry standard, offering deep penetration and stable absorption; 515 nm (green light) is suitable for thin glass (thickness <200 μm), and 343 nm (ultraviolet) is used for high-absorption materials. The laser energy density is 1.2 ± 0.2 J / cm². The midpoint distance between adjacent laser-modified points is greater than 100 μm, preferably between 200 and 300 μm.

[0031] In step 2, the pressing pressure between the interlayer dielectric layer 5 and the superimposed glass layer 6 is between 0.1-1 MPa, the pressing time is 100 s, and the pressing temperature is 90℃. The bonding pressure between the interlayer dielectric layer 5 and the superimposed glass layer 6 is between 0.1-1 MPa, the bonding time is 100 s, and the bonding temperature is 90℃. In one fabrication method, an RDL redistribution layer 2 is first fabricated on one side of the glass Core layer 1, and then the fabricated side is protected by temporary bonding. Subsequently, an RDL redistribution layer 2 is fabricated on the other side. In another fabrication method, an RDL redistribution layer 2 and an add-in unit 4 are first fabricated on one side of the glass Core layer 1, and then temporary bonding is performed for protection. Then, the corresponding fabrication process is performed on the other side, and finally the temporary bonding is released.

[0032] In step 4, a CO2 laser is used to create openings in the interlayer dielectric layer 5.

[0033] Example 5: A method for manufacturing a BGV structure that enhances the adhesion of electroplated copper to a glass substrate, for manufacturing the BGV structure as shown in Example 2, comprising: Step 1: Prepare glass core layer 1 and core conductive structure 3; Step 1.1: Perform laser modification on the glass core layer 1. During the laser modification process, the laser focus is set close to the upper surface of the glass core layer 1, and the laser modification area does not extend to the bottom surface of the glass core layer 1. Step 1.2: Perform wet etching on the laser-modified glass Core layer 1 to form BGV blind vias; Step 1.3: Deposit a seed layer in the BGV blind via and electroplate copper to fill it to form BGV via copper 32. Then, perform CMP treatment on the upper surface of the glass Core layer 1 to remove the surface copper. Step 1.4: Thin the bottom surface of the glass Core layer 1 and perform CMP treatment so that the bottom of the BGV via copper 32 is exposed on the bottom surface of the glass Core layer 1 to form the Core conduction structure 3. Step 1.5: Prepare RDL redistribution layer 2 on the first and second surfaces of glass Core layer 1 using a semi-additive method; Step 2: Sequentially press the interlayer dielectric layer 5 and the uplift glass layer 6 onto the first surface side and / or the second surface side of the glass core layer 1; Step 3: Laser modification is performed on the additive glass layer 6 to form an area to be etched and modified within the additive glass layer 6. Then, wet etching is performed on the laser-modified additive glass layer 6 to form an additive BGV hole 81 extending towards the interlayer dielectric layer 5 in the additive glass layer 6. When the etching front reaches the interface between the additive glass layer 6 and the interlayer dielectric layer 5, the etching solution extends laterally from the bottom interface edge region of the additive BGV hole 81 and performs lateral etching on the bottom edge region of the additive glass layer 6 near the interlayer dielectric layer 5 to form a side cutout 83 that extends laterally relative to the hole body of the additive BGV hole 81. Step 4: Perform via processing on the interlayer dielectric layer 5 to form a dielectric layer via 82 connecting the add-on BGV via 81 and the RDL redistribution layer 2; Step 5: Form the augmented metal conductive portion 8 in the augmented BGV hole 81, the side cut portion 83 and the dielectric layer through hole 82, and then form the augmented metal patterned layer 7 electrically connected to the augmented metal conductive portion 8 on the side of the augmented glass layer 6 away from the interlayer dielectric layer 5. Step 6: Repeat steps 2-5 to form at least one layer of add-on unit 4 on at least one side of glass Core layer 1.

[0034] The Core fabrication route described in this embodiment reduces the difficulty of directly filling copper through high aspect ratio TGV vias and helps improve the quality of copper filling in the Core layer and the reliability of the glass substrate.

[0035] Specifically, in steps 1 and 3, wet etching uses either HF or NaOH etching solution. Hydrofluoric acid (HF) is currently the dominant wet etching reagent in industrial mass production and is suitable for borosilicate glass (such as Corning Eagle XG and Schott AF32). Sodium hydroxide (NaOH) can theoretically be used for soda-lime glass. When using HF etching solution, the concentration of HF etching solution is between 40% and 50%, and the etching temperature is between 20 and 45°C. During the etching process, 40 kHz ultrasound and 5 rpm rotation are used to promote the renewal of the etching solution in the hole and reduce the retention of reaction products or bubbles in the hole. When using HF etching solution, the aperture angle of the TGV via wall is between 85-87°. If using NaOH solution, the aperture angle of the TGV via wall wall is between 86-89°. In step 1, a picosecond or femtosecond laser is used. Picosecond lasers have a pulse width between 1 and 10 ps, ​​suitable for mass production; femtosecond lasers have a pulse width less than 350 fs, suitable for high-precision or small-sized aperture processing. The laser wavelength can be 1030 nm, 5151 nm, or 343 nm. 1030 nm is the industry standard, offering deep penetration and stable absorption; 515 nm (green light) is suitable for thin glass (thickness <200 μm), and 343 nm (ultraviolet) is used for high-absorption materials. The laser energy density is 1.2 ± 0.2 J / cm². The midpoint distance between adjacent laser-modified points is greater than 100 μm, preferably between 200 and 300 μm.

[0036] In step 2, the pressing pressure between the interlayer dielectric layer 5 and the superimposed glass layer 6 is between 0.1-1 MPa, the pressing time is 100 s, and the pressing temperature is 90℃. The bonding pressure between the interlayer dielectric layer 5 and the superimposed glass layer 6 is between 0.1-1 MPa, the bonding time is 100 s, and the bonding temperature is 90℃. In one fabrication method, an RDL redistribution layer 2 is first fabricated on one side of the glass Core layer 1, and then the fabricated side is protected by temporary bonding. Subsequently, an RDL redistribution layer 2 is fabricated on the other side. In another fabrication method, an RDL redistribution layer 2 and an add-in unit 4 are first fabricated on one side of the glass Core layer 1, and then temporary bonding is performed for protection. Then, the corresponding fabrication process is performed on the other side, and finally the temporary bonding is released.

[0037] In step 4, a CO2 laser is used to create openings in the interlayer dielectric layer 5.

[0038] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make inventive modifications to this embodiment as needed, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A BGV structure for enhancing the adhesion of electroplated copper to a glass substrate, characterized in that, include: The glass core layer (1) has a first surface and a second surface disposed opposite to each other, and both the first surface side and the second surface side of the glass core layer (1) are provided with an RDL redistribution layer (2); The Core conduction structure (3) extends along the thickness direction of the glass Core layer (1) and is electrically connected to the RDL redistribution layer (2); The layer addition unit (4) is provided in at least one set, which is respectively disposed on the first surface side and / or the second surface side of the glass core layer (1), including an interlayer dielectric layer (5), an addition glass layer (6), an addition metal pattern layer (7) and an addition metal conductive part (8) arranged sequentially from the inside to the outside. The added metal conductive part (8) includes an added BGV hole (81) opened in the added glass layer (6) and a dielectric layer through hole (82) opened in the interlayer dielectric layer (5) and connected to the added BGV hole (81). The added BGV hole (81) has a side cutout (83) at one end near the interlayer dielectric layer (5). The side cutout (83) extends laterally along the bottom periphery of the added BGV hole (81) relative to the hole body of the added BGV hole (81). The added metal conductive portion (8) further includes added BGV hole copper (84) filled in the added BGV hole (81), anchoring copper portion (85) filled in the side hole portion (83), and connecting copper portion (86) filled in the dielectric layer conductive hole (82). The anchoring copper portion (85) forms a mechanical anchoring structure at one end of the added BGV hole (81) near the interlayer dielectric layer (5) to restrict the detachment of the added BGV hole copper (84).

2. The BGV structure for enhancing the adhesion of electroplated copper to a glass substrate according to claim 1, characterized in that, The side cutout (83) is continuously distributed or at least partially distributed around the bottom periphery of the BGV hole (81) of the layered layer, and the anchoring copper part (85) is filled in the side cutout (83) in an annular hanging wall shape.

3. The BGV structure for enhancing the adhesion of electroplated copper to a glass substrate according to claim 1, characterized in that, The bottom CD of the BGV hole (81) near the interlayer dielectric layer (5) is 0.8-2 times the top CD of the side away from the interlayer dielectric layer (5). The size of the dielectric layer via (82) near the BGV hole (81) is smaller than the minimum aperture of the BGV hole (81) along the thickness direction of the BGV hole (81).

4. The BGV structure for enhancing the adhesion of electroplated copper to a glass substrate according to claim 1, characterized in that, The interlayer dielectric layer (5) is an ABF layer, the thickness of the glass core layer (1) and the added glass layer (6) is between 100-400 μm, and the thickness of the interlayer dielectric layer (5) is between 20-60 μm.

5. The BGV structure for enhancing the adhesion of electroplated copper to a glass substrate according to any one of claims 1-4, characterized in that, The Core conduction structure (3) is a TGV via copper (31) filled in the TGV via penetrating the glass Core layer (1), and the TGV via copper (31) penetrates the first surface and the second surface of the glass Core layer (1).

6. A BGV structure for enhancing the adhesion of electroplated copper to a glass substrate according to any one of claims 1-4, characterized in that, The Core conduction structure (3) is a BGV via copper (32) filled in the BGV blind via of the glass Core layer (1). One end of the BGV via copper (32) is exposed on the first surface of the glass Core layer (1). After being thinned on the second surface side of the glass Core layer (1), the other end of the BGV via copper (32) is exposed on the second surface of the glass Core layer (1). The bottom CD of the BGV via copper (32) on the second surface is >20μm.

7. A method for manufacturing a BGV structure that enhances the adhesion of electroplated copper to a glass substrate, characterized in that, include: Step 1: Prepare the glass core layer (1) and the core conductive structure (3); Step 2: Press the interlayer dielectric layer (5) and the uplift glass layer (6) sequentially onto the first surface side and / or the second surface side of the glass core layer (1); Step 3: Laser modification is performed on the addition glass layer (6) to form an area to be etched and modified in the addition glass layer (6). Then, wet etching is performed on the laser-modified addition glass layer (6) to form an addition BGV hole (81) extending towards the side of the interlayer dielectric layer (5) in the addition glass layer (6). When the etching front reaches the interface between the addition glass layer (6) and the interlayer dielectric layer (5), the etching solution extends laterally from the bottom interface edge area of ​​the addition BGV hole (81) and laterally etches the bottom edge area of ​​the addition glass layer (6) near the interlayer dielectric layer (5) to form a side cutout (83) that extends laterally relative to the hole body of the addition BGV hole (81). Step 4: Perform an opening process on the interlayer dielectric layer (5) to form a dielectric layer via (82) that connects the add-on BGV via (81) and the RDL redistribution layer (2); Step 5: Form an augmented metal conductive portion (8) in the augmented BGV hole (81), the side cutout (83) and the dielectric layer through hole (82), and then form an augmented metal patterned layer (7) electrically connected to the augmented metal conductive portion (8) on the side of the augmented glass layer (6) away from the interlayer dielectric layer (5); Step 6: Repeat steps 2-5 to form at least one layer of the added layer unit (4) on at least one side of the glass core layer (1).

8. The method for manufacturing a BGV structure with enhanced adhesion to electroplated copper on a glass substrate according to claim 7, characterized in that, Step 1 includes: Step 1.1: Laser modification is performed on the glass core layer (1). During the laser modification process, the laser focus is set at a position close to 1 / 2 of the thickness of the glass core layer (1), and a TGV via is formed through the glass core layer (1) by wet etching. Step 1.2: Deposit a seed layer in the TGV via and electroplate copper to fill it to form TGV via copper (31); Step 1.3: Perform double-sided CMP treatment on the glass Core layer (1); Step 1.4: Prepare an RDL redistribution layer (2) on the first and second surfaces of the glass Core layer (1) using a semi-additive method.

9. The method for manufacturing a BGV structure with enhanced adhesion to electroplated copper on a glass substrate according to claim 7, characterized in that, Step 1 includes: Step 1.1: Perform laser modification on the glass Core layer (1). During the laser modification process, the laser focus is set close to the upper surface of the glass Core layer (1) and the laser modification area does not extend to the bottom surface of the glass Core layer (1). Step 1.2: Wet etching is performed on the laser-modified glass Core layer (1) to form BGV blind holes; Step 1.3: Deposit a seed layer in the BGV blind via and electroplate copper to fill it to form BGV via copper (32), and then perform CMP treatment on the upper surface of the glass Core layer (1) to remove the surface copper. Step 1.4: Thin the bottom surface of the glass Core layer (1) and perform CMP treatment so that the bottom of the BGV hole copper (32) is exposed on the bottom surface of the glass Core layer (1) to form the Core conduction structure (3). Step 1.5: Prepare an RDL redistribution layer (2) on the first and second surfaces of the glass Core layer (1) using a semi-additive method.

10. A method for manufacturing a BGV structure with enhanced adhesion to electroplated copper on a glass substrate according to claim 8 or 9, characterized in that, In step 2, the pressing pressure of the interlayer dielectric layer (5) and the superimposed glass layer (6) is between 0.1-1 MPa, the pressing time is 100 s, and the pressing temperature is 90 ℃. In steps 1 and 3, wet etching uses HF etching solution or NaOH etching solution; In step 4, a CO2 laser is used to open a hole in the interlayer dielectric layer (5).

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