Structure and manufacturing method of filter

Abstract

The invention discloses a filter structure and a manufacturing method, the filter structure comprises a first insulating layer, a second insulating layer, a glass substrate, at least one inductor and at least one capacitor, the glass substrate is located between the first insulating layer and the second insulating layer, the glass substrate comprises a first surface and a second surface which are oppositely arranged, the glass substrate is provided with a plurality of glass through holes; the inductor comprises a plurality of first parts located on the first surface of the glass substrate, a plurality of second parts located on the second surface of the glass substrate and a plurality of metal columns penetrating through glass through holes, the metal columns are connected with the first parts and the second parts of the inductor, the first parts of the inductor comprise composite metal layers, and the second parts of the inductor comprise composite metal layers. The composite metal layer comprises a titanium layer and an aluminum layer; the capacitor comprises the composite metal layer, stress expansion of thick metal can be reduced, and stress accumulation of the glass substrate is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of wafers, and in particular relates to a structure and a manufacturing method of a filter. Background Art

[0002] 3D integrated passive devices mainly use TSV / TGV (vias) and high-temperature curing materials on the front and back of the structure to achieve sealing protection and rewiring. In actual applications, it has been found that the circumferential stress of the copper pillar causes cracks in the glass substrate, which is prone to a crack extension effect in reliability, leading to the invasion of water vapor and the deterioration of the inductor Q value, which in turn leads to the failure of the filter module and the resonance performance of the filter. In addition, the formation process of the via filling material requires a high-temperature annealing process, which will cause stress accumulation in the substrate structure, resulting in tensile stress and damage to the substrate structure. For example, during the manufacturing process, especially baking or stress-bearing process, the circumferential stress generated by the copper pillar squeezing the glass makes the wafer fragile, resulting in cracks and scrapping in the above process, and the process cracking rate is high. Summary of the invention

[0003] In order to solve the above problems existing in the prior art, the present application provides a filter structure and manufacturing method, which reduces the stress accumulation of the substrate and the influence of the high temperature process on the product by adding a composite metal layer, optimizing the structure and process preparation flow, and adopts the following technical solutions:

[0004] A filter structure includes: a first insulating layer and a second insulating layer arranged opposite to each other, and a glass substrate located between the first insulating layer and the second insulating layer, the glass substrate including a first surface and a second surface arranged opposite to each other, and the glass substrate having a plurality of glass through holes; at least one inductor, the inductor including a plurality of first parts located on the first surface of the glass substrate, a plurality of second parts located on the second surface of the glass substrate, and a plurality of metal pillars penetrating the glass through holes, a spiral conductor structure of the inductor is formed by connecting the first part, the metal pillar and the second part of the inductor, the metal pillar connecting the first part and the second part of the inductor, the first part of the inductor including a composite metal layer, the composite metal layer including a titanium layer and an aluminum layer; at least one capacitor, the capacitor including the composite metal layer. Adding the composite metal layer can alleviate the stress accumulation in the glass substrate structure during the high-temperature process and avoid damage to the glass substrate due to tensile stress. The titanium layer in the composite metal layer can reduce stress and improve adhesion between materials in the filter.

[0005] Preferably, the structure of the filter further includes a conductive structure, and the conductive structure connects the first part of the inductor and the capacitor.

[0006] Further preferably, the first part of the inductor includes a first metal layer between the glass substrate and the conductive structure, and the composite metal layer of the inductor corresponding to the metal column, the composite metal layer of the inductor is located between the first metal layer and the glass substrate, the composite metal layer of the inductor includes an aluminum layer between the first metal layer and the glass substrate, and a titanium layer between the aluminum layer and the glass substrate, and the second part of the inductor includes a second metal layer. The composite metal layer of the inductor can alleviate the extrusion of the metal column on the glass substrate, and avoid cracks in the glass substrate and water vapor entering due to the direct connection of the first metal layer to the metal column.

[0007] Further preferably, the metal column connects the composite metal layer of the inductor and the second part of the inductor, one metal column corresponds to one composite metal layer of the inductor, and the area of ​​the composite metal layer of the inductor is larger than the cross-sectional area of ​​the metal column on the glass substrate.

[0008] Further preferably, the area range of the composite metal layer of the inductor is 1.3 to 2.4 times the cross-sectional area of ​​the metal column on the first surface of the glass substrate. If the area of ​​the composite metal layer of the inductor is smaller than this range, it cannot cover the cross-sectional area of ​​the metal column on the glass substrate, resulting in failure to reduce cracks caused by the metal column squeezing the glass substrate. If it is larger than this area range, the Q value of the inductor will decrease.

[0009] Further preferably, the capacitor includes a third insulating layer between the glass substrate and the conductive structure, a composite metal layer between the glass substrate and the third insulating layer, and a third metal layer between the conductive structure and the third insulating layer, and the composite metal layer of the capacitor includes an aluminum layer between the glass substrate and the third insulating layer, and a titanium layer between the glass substrate and the aluminum layer. The composite metal layer of the capacitor serves as part of the lower plate of the capacitor, wherein the aluminum layer and the titanium layer are prepared by a magnetron sputtering process, the flatness is improved, the breakdown voltage of the capacitor is increased, and the performance of the filter is optimized.

[0010] Further preferably, the composite metal layer of the capacitor is connected to one of the metal pillars of the inductor. The composite metal layer of the capacitor serves as a part of the lower plate of the capacitor and also as the composite metal layer of the inductor, that is, the lower plate of the capacitor and a metal pillar of the inductor share a composite metal layer, which ensures the performance of the filter while reducing the volume of the filter.

[0011] Further preferably, a first auxiliary layer between the first metal layer and the composite metal layer of the inductor, a second auxiliary layer between the metal column and the second metal layer, and a third auxiliary layer between the third insulating layer and the composite metal layer of the capacitor are further included. The first auxiliary layer, the second auxiliary layer and the third auxiliary layer can improve the adhesion and structural stability between materials, and at the same time help reduce the stress accumulation of the filter.

[0012] Further preferably, the thickness of the aluminum layer is less than or equal to 3 μm, the thickness of the titanium layer is less than or equal to 1 μm, the thickness of the first metal layer is greater than or equal to 3 μm, and the thickness of the second metal layer is greater than or equal to 3 μm.

[0013] On the other hand, a method for manufacturing a filter comprises the following steps:

[0014] S1: forming a plurality of blind holes on a glass substrate;

[0015] S2: filling copper in the blind hole and forming a copper layer on the first surface of the glass substrate;

[0016] S3: removing the copper layer on the first surface of the glass substrate;

[0017] S4: preparing a composite metal layer and a MIM capacitor on the first surface of the glass substrate;

[0018] S5: preparing a first insulating layer, a first metal layer and a conductive structure;

[0019] S6: preparing a second metal layer on the second surface of the glass substrate by temporary bonding;

[0020] S7: forming a second insulating layer on the second surface of the glass substrate;

[0021] S8: After debonding and wafer dicing, the complete filter structure is achieved.

[0022] Preferably, the composite metal layer includes a titanium layer and an aluminum layer, and S4 includes: preparing the titanium layer and the aluminum layer by a magnetron sputtering process. The preparation method is conducive to reducing particle pollution, reducing defective rate, reducing the influence of warping, improving film quality, reducing the influence of baking and force process on the glass substrate, reducing cracks caused by metal columns squeezing the glass substrate, reducing the process cracking rate, and preparing a flatter capacitor bottom plate by a magnetron sputtering process, so that the breakdown voltage of the capacitor is improved.

[0023] Compared with the prior art, the beneficial results of the present invention are:

[0024] (1) The chipping rate of the process is reduced, the composite metal layer is added, the circumferential stress caused by the metal column squeezing the glass during the baking and stress-bearing process is reduced, the wafer firmness is enhanced, the chipping is avoided and the cost is reduced.

[0025] (2) Improve reliability by avoiding the extension effect in the circumferential cracks generated by the metal pillars, which would cause water vapor to enter the glass substrate, prevent the inductor Q value from deteriorating, and thus affect the resonant performance of the filter. At the same time, it reduces the separation between layers caused by the stress expansion of thick metal, thereby increasing the reliability of the filter.

[0026] (3) A composite metal layer is used as part of the lower electrode plate of the capacitor, wherein the aluminum layer and the titanium layer are prepared by a magnetron sputtering process, which improves the flatness, increases the breakdown voltage of the capacitor, reduces the unevenness problem caused by the stress release of the thick metal as an electrode, and optimizes the performance of the filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and together with the description are used to explain the principles of the present invention. Other embodiments and many expected advantages of the embodiments will be readily appreciated as they become better understood by reference to the following detailed description. Other features, objects and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings:

[0028] Figure 1 is a schematic cross-sectional view of the structure of a filter and a composite metal layer structure according to a specific embodiment of the present application;

[0029] Figure 2 is a flow chart of a method for manufacturing a filter according to a specific embodiment of the present application;

[0030] Figure 3 is a schematic structural 3D diagram of a filter according to a specific embodiment of the present application;

[0031] Figure 4 is a schematic diagram of a filter stress simulation model without a composite metal layer according to a specific embodiment of the present application;

[0032] Figure 5 is a cross-sectional schematic diagram corresponding to a stress simulation model of a filter without a composite metal layer according to a specific embodiment of the present application;

[0033] Figure 6 This is a schematic diagram of the main stress distribution of a filter without a composite metal layer in a specific embodiment of the present application;

[0034] Figure 7 It is a schematic diagram of a stress simulation model of a filter with a composite metal layer according to a specific embodiment of the present application;

[0035] Figure 8 It is a cross-sectional schematic diagram corresponding to a stress simulation model of a filter with a composite metal layer according to a specific embodiment of the present application;

[0036] Fig. 9 It is a schematic diagram of the principal stress distribution of a filter with a composite metal layer according to a specific embodiment of the present application.

[0037] The meaning of the numbers in the figure are: 1. glass substrate; 2. metal column; 3. conductive structure; 4. first auxiliary layer; 5. composite metal layer; 6. first metal layer; 7. second metal layer; 8. third metal layer; 9. third insulating layer. DETAILED DESCRIPTION

[0038] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0039] In the description of the present invention, it should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Directional terms are used with reference to the orientation of the described figures, such as "top", "bottom", "left", "right", "upper", "lower", etc. Because the components of the embodiments can be positioned in several different orientations, directional terms are used for the purpose of illustration and the directional terms are by no means restrictive. The terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection through an intermediate medium, or a communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0040] In the first aspect, the present application proposes a filter structure. Figure 1 and Figure 2 A schematic cross-sectional view of a filter structure according to a specific embodiment of the present invention is shown. The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

[0041] Embodiment 1:

[0042] A filter structure comprises: a first insulating layer, a second insulating layer, a glass substrate 1, at least one inductor, at least one capacitor and a conductive structure 3, wherein the first insulating layer and the second insulating layer are arranged opposite to each other, the glass substrate 1 is located between the first insulating layer and the second insulating layer, the glass substrate 1 comprises a first surface and a second surface arranged opposite to each other, the first insulating layer is located on the first surface of the glass substrate 1, the second insulating layer is located on the second surface of the glass substrate 1, and the glass substrate 1 has a plurality of through-glass holes; the inductor comprises a plurality of first parts located on the first surface of the glass substrate 1, a plurality of second parts located on the second surface of the glass substrate 1 and a plurality of metal pillars 2 penetrating the through-glass holes, a spiral conductor structure of the inductor is formed by connecting the first part of the inductor, the metal pillars 2 and the second part, the metal pillars 2 connect the first part and the second part of the inductor, the first part of the inductor comprises a composite metal layer 5, and the composite metal layer 5 of the inductor is connected to the metal pillars 2; the capacitor comprises a composite metal layer 5, and the composite metal layer 5 comprises a titanium layer and an aluminum layer; and the conductive structure 3 connects the first part of the inductor and the capacitor.

[0043] Adding the composite metal layer 5 can alleviate the stress accumulation in the structure of the glass substrate 1 during the high-temperature process, enhance reliability, reduce the surface effect and interlayer separation caused by the expansion of thick metal stress, and avoid damage to the glass substrate 1 due to tensile stress. The titanium layer in the composite metal layer 5 can reduce stress in the filter and improve the adhesion between materials. The aluminum layer and the titanium layer connect the glass through hole and serve as a release layer.

[0044] Optionally, the first part of the inductor includes a first metal layer 6 between the glass substrate 1 and the conductive structure 3, and a composite metal layer 5 corresponding to the metal column 2, the composite metal layer 5 of the inductor is located between the first metal layer 6 and the glass substrate 1, the composite metal layer 5 includes an aluminum layer between the first metal layer 6 and the glass substrate 1, and a titanium layer between the aluminum layer and the glass substrate 1, and the second part of the inductor includes a second metal layer 7. The composite metal layer 5 can relieve the extrusion of the glass substrate 1 by the metal column 2, and avoid cracks in the glass substrate 1 and water vapor entering due to the direct connection of the first metal layer 6 to the metal column 2, the aluminum layer and the titanium layer can relieve the stress of the metal column 2 on the glass substrate 1 in the high-temperature process, and reduce the stress accumulation of the glass substrate 1, wherein the titanium layer can also improve the adhesion between materials.

[0045] Optionally, the metal column 2 connects the composite metal layer 5 and the second part of the inductor, one metal column 2 corresponds to one composite metal layer 5 , and the area of ​​the composite metal layer 5 is greater than or equal to the area of ​​the metal column 2 in the cross section of the glass substrate 1 .

[0046] In a specific embodiment, the area range of the composite metal layer 5 of the inductor is 1.3 to 2.4 times the cross-sectional area of ​​the metal column 2 on the first surface of the glass substrate 1. Controlling the composite metal layer 5 of the inductor within this area range can ensure that the performance of the inductor is not affected. If it exceeds this range, the performance of the inductor will decrease. In a specific embodiment, when the composite metal layer 5 of the inductor is circular and the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1 is circular, the radius of the composite metal layer 5 of the inductor is 12 to 23 μm longer than the radius of the cross-sectional position of the glass through hole on the first surface of the glass substrate 1; when the composite metal layer 5 of the inductor is rectangular and the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1 is circular, the shortest distance between the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1 and the edge of the composite metal layer 5 of the inductor is 12 to 21 μm; when the composite metal layer 5 of the inductor is rectangular and the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1 is rectangular, the side length of the composite metal layer 5 of the inductor is 25 to 41 μm longer than the side length of the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1.

[0047] Optionally, if the area of ​​the composite metal layer 5 of the inductor is smaller than 1.3 times the cross-sectional area of ​​the metal column 2 on the glass substrate 1, good coverage and stress buffering effect cannot be achieved in actual production; if the area of ​​the composite metal layer 5 of the inductor is larger than 2.4 times the cross-sectional area of ​​the metal column 2 on the glass substrate 1, the conductive performance of copper cannot be brought into play, resulting in excessive impedance of the inductor, high loss, and decreased inductor Q value.

[0048] In a specific embodiment, the through glass hole and the metal column 2 can be one of a column, a cone, and a frustum.

[0049] In a specific embodiment, the area of ​​the composite metal layer 5 of the inductor is smaller than the first metal layer 6 located in the inductor. Specifically, in the inductor, the composite metal layer 5 is only arranged at the connection position centered on the glass through hole and the metal column 2, while the composite metal layer 5 is not arranged on the portion where the two metal columns 2 are connected on the first surface of the glass substrate 1, and the two metal columns 2 on the first surface are connected by the first metal layer 6.

[0050] In a specific embodiment, the capacitor is a MIM (metal-insulator-metal) capacitor, including a third insulating layer 9 between the glass substrate 1 and the conductive structure 3, a composite metal layer 5 between the glass substrate 1 and the third insulating layer 9, and a third metal layer 8 between the conductive structure 3 and the third insulating layer 9. The composite metal layer 5 of the capacitor includes an aluminum layer between the glass substrate 1 and the third insulating layer 9, and a titanium layer between the glass substrate 1 and the aluminum layer. In other embodiments, other types of capacitors can also be prepared. The composite metal layer 5 can be used as an electrode structure of a MIM capacitor to reduce the unevenness problem caused by the stress release of thick metal as an electrode.

[0051] In a specific embodiment, the lower electrode plate of the capacitor is composed of a composite metal layer 5, and a third auxiliary layer between the third insulating layer 9 and the composite metal layer 5, that is, the composition of the lower plate of the capacitor is titanium layer-aluminum layer-titanium layer. Optionally, the composition of the upper electrode plate of the capacitor can be the same as that of the lower plate, which is titanium layer-aluminum layer-titanium layer. The third metal layer 8 can also be a combination of one or more metal materials such as aluminum, titanium, copper, silver, and gold. When the electrode plate of the capacitor contains an aluminum layer and a titanium layer, the unevenness problem caused by the stress release of the thick metal as an electrode can be alleviated, and the internal stress caused by the change of the lattice during annealing can be alleviated. At the same time, the aluminum layer and the titanium layer are prepared by a magnetron sputtering process, the flatness is improved, and the breakdown voltage of the capacitor is increased.

[0052] The structure of the filter also includes a first auxiliary layer 4 between the first metal layer 6 and the composite metal layer 5 of the inductor, a second auxiliary layer between the metal column 2 and the second metal layer 7, and a third auxiliary layer between the third insulating layer 9 and the composite metal layer 5 of the capacitor. In a specific embodiment, an auxiliary layer is provided between each layer of metal and metal, and between metal and non-metal. The material of the auxiliary layer is titanium. In other embodiments, it can also be titanium nitride or other titanium compounds. The auxiliary layer can improve the adhesion and structural stability between materials, and at the same time help reduce the stress accumulation of thick metal in the glass substrate, thereby maintaining the stability of the inductor, capacitor and filter.

[0053] In a specific embodiment, the thickness of the aluminum layer is less than or equal to 3 μm, the thickness of the titanium layer is less than or equal to 1 μm, the thickness of the first metal layer 6 is greater than or equal to 3 μm, and the thickness of the second metal layer 7 is greater than or equal to 3 μm.

[0054] like Figure 1As shown, it is a schematic diagram, including a glass substrate 1, a through glass via (TGV), and a metal column 2 composed of metal copper filled in the through glass via. The glass substrate 1 has a first surface and a second surface arranged opposite to each other. The first part of the inductor and the MIM capacitor are located on the first surface of the glass substrate 1. The through glass via connects the first part of the inductor. The first part of the inductor is a titanium layer of a composite metal layer 5, an aluminum layer of the composite metal layer 5, a first auxiliary layer 4, and a first metal layer 6 in sequence from close to the first surface of the glass substrate 1 to far away from the first surface of the glass substrate 1; the MIM capacitor includes a third metal layer 8, a third insulating layer 9 and a lower electrode The lower electrode plate comprises a composite metal layer 5, and the first surface of the lower electrode plate from close to to far from the glass substrate 1 is a titanium layer of the composite metal layer 5, an aluminum layer of the composite metal layer 5, and a third auxiliary layer, the third metal layer 8 is connected to a conductive structure 3, and the area of ​​the composite metal layer 5 of the inductor is 1.3 to 2.4 times the cross-sectional area of ​​the metal column 2 and the first surface of the glass substrate 1; the second surface of the glass substrate 1 comprises a second insulating layer, and a second metal layer 7 between the second insulating layer and the second surface of the glass substrate 1, and a second auxiliary layer is included between the metal column 2 and the second metal layer 7.

[0055] In a specific embodiment, the first metal layer 6 and the second metal layer 7 are made of copper, and in other embodiments, they may be other metals; the material of the third metal layer 8 is a combination of one or more of aluminum, copper, titanium, gold, silver, etc. The material of the first auxiliary layer 4, the second auxiliary layer and the third auxiliary layer is titanium, and in other embodiments, they may be titanium compounds, such as titanium nitride; the material of the first insulating layer and the second insulating layer is polyimide, and in other embodiments, they may be one of phenolic resin, epoxy resin and other polymer materials; the material of the third insulating layer 9 is silicon nitride, and in other embodiments, it may be one of silicon dioxide and other high dielectric constant materials; the conductive structure 3 is a metal wiring made of copper, and in other embodiments, it may be other metals. In other embodiments, the material of the composite metal layer may also be a combination of one or more materials of other submicron materials such as gold, silver, titanium, aluminum, copper, etc.

[0056] Embodiment 2:

[0057] A filter structure comprises: a first insulating layer, a second insulating layer, a glass substrate 1, at least one inductor, at least one capacitor and a conductive structure 3, wherein the first insulating layer and the second insulating layer are arranged opposite to each other, the glass substrate 1 is located between the first insulating layer and the second insulating layer, the glass substrate 1 comprises a first surface and a second surface arranged opposite to each other, the first insulating layer is located on the first surface of the glass substrate 1, the second insulating layer is located on the second surface of the glass substrate 1, and the glass substrate 1 has a plurality of through-glass holes; the inductor comprises a plurality of first parts located on the first surface of the glass substrate 1, a plurality of second parts located on the second surface of the glass substrate 1 and a plurality of metal pillars 2 penetrating the through-glass holes, a spiral conductor structure of the inductor is formed by connecting the first part of the inductor, the metal pillars 2 and the second part, the metal pillars 2 connect the first part and the second part of the inductor, the first part of the inductor comprises a composite metal layer 5, and the composite metal layer 5 of the inductor is connected to the metal pillars 2; the capacitor comprises a composite metal layer 5, and the composite metal layer 5 comprises a titanium layer and an aluminum layer; and the conductive structure 3 connects the first part of the inductor and the capacitor. Adding a composite metal layer can alleviate the stress accumulation in the structure of the glass substrate 1 during the high-temperature process, enhance reliability, reduce the surface effect and interlayer separation caused by the expansion of thick metal stress, avoid damage to the glass substrate 1 due to tensile stress, and avoid water vapor entering the circumferential cracks caused by the metal column 2 squeezing the glass substrate 1, thereby affecting the resonance performance of the filter. The titanium layer in the composite metal layer 5 can reduce stress in the filter and improve the adhesion between materials. The aluminum layer and the titanium layer connect the glass through hole and serve as a release layer.

[0058] In a specific embodiment, the through glass via and the metal column 2 can be one of a column, a cone and a frustum.

[0059] Optionally, the first part of the inductor includes a first metal layer 6 between the glass substrate 1 and the conductive structure 3, and a composite metal layer 5 corresponding to the metal column 2. Since the inductor of the filter includes a plurality of metal columns 2, the first surface of the glass substrate 1 corresponds to the same number of composite metal layers 5 of the inductor. The composite metal layer 5 of the inductor is located between the first metal layer 6 and the glass substrate 1. The composite metal layer 5 includes an aluminum layer between the first metal layer 6 and the glass substrate 1, and a titanium layer between the aluminum layer and the glass substrate 1. The second part of the inductor includes a second metal layer 7. The aluminum layer and the titanium layer can relieve the stress of the metal column 2 on the glass substrate 1 during the high-temperature process and reduce the stress accumulation of the glass substrate 1. The titanium layer can also improve the adhesion between materials.

[0060] Optionally, the metal column 2 connects the composite metal layer 5 of the inductor and the second part of the inductor, one metal column 2 corresponds to one composite metal layer 5 of the inductor, and the area range of the composite metal layer 5 of the inductor is 1.3 to 2.4 times the cross-sectional area of ​​the metal column 2 on the glass substrate 1. By controlling the composite metal layer 5 within this area range, it can be ensured that the performance of the inductor is not affected. If the area is exceeded, the performance of the inductor decreases. In a specific embodiment, when the composite metal layer 5 of the inductor is circular and the cross-sectional position of the metal column 2 on the first surface of the glass substrate 1 is circular, The radius of the composite metal layer 5 of the inductor is 15 μm longer than the radius of the glass through hole in the cross-section of the first surface of the glass substrate 1; when the composite metal layer 5 of the inductor is rectangular, and the cross-section position of the metal column 2 on the first surface of the glass substrate 1 is circular, the side length of the composite metal layer 5 of the inductor is 30 μm longer than the diameter of the cross-section of the metal column 2 on the first surface of the glass substrate 1; when the composite metal layer 5 of the inductor is rectangular, and the cross-section position of the metal column 2 on the first surface of the glass substrate 1 is rectangular, the side length of the composite metal layer 5 of the inductor is 30 μm longer than the side length of the cross-section of the metal column 2 on the first surface of the glass substrate 1.

[0061] In a specific embodiment, the area of ​​the first metal layer 6 located in the inductor is greater than or equal to the composite metal layer 5 of the inductor. Specifically, in the inductor, the composite metal layer 5 is only provided at the connection position centered on the glass through hole and the metal column 2, while the composite metal layer 5 is not provided at the portion where the two metal columns 2 are connected on the first surface of the glass substrate 1, and the two metal columns 2 on the first surface are connected by the first metal layer 6.

[0062] Optionally, the composite metal layer 5 of the capacitor is connected to one of the metal pillars 2 of the inductor. That is, the composite metal layer 5 of the capacitor serves as a part of the lower plate of the capacitor and also serves as the composite metal layer 5 of the inductor, that is, the lower plate of the capacitor and a metal pillar of the inductor share a composite metal layer 5. Such a setting can reduce the volume of the filter while ensuring the performance of the filter, avoiding waste of materials and space. The composite metal layer 5, as the electrode structure of the capacitor, can alleviate the unevenness problem caused by the stress release of the thick metal as the electrode, improve the performance of the filter, and at the same time avoid the metal pillar 2 squeezing the glass substrate 1 to produce a cracking effect, prevent water vapor from entering the cracks, and thus reduce the reliability of the filter.

[0063] In a specific embodiment, the capacitor is a MIM (metal-insulator-metal) capacitor, including a third insulating layer 9 located between the glass substrate 1 and the conductive structure 3, a composite metal layer 5 located between the glass substrate 1 and the third insulating layer 9, and a third metal layer 8 located between the conductive structure 3 and the third insulating layer 9. The composite metal layer 5 of the capacitor includes an aluminum layer between the glass substrate 1 and the third insulating layer 9, and a titanium layer between the glass substrate 1 and the aluminum layer, wherein the aluminum layer and the titanium layer are prepared by a magnetron sputtering process, the flatness is improved, the breakdown voltage of the capacitor is increased, and the performance of the filter is optimized. In other embodiments, other types of capacitors can also be prepared.

[0064] In a specific embodiment, the lower electrode plate of the capacitor is composed of a composite metal layer 5, and a third auxiliary layer between the third insulating layer 9 and the composite metal layer 5, that is, the composition of the lower plate of the capacitor is titanium layer-aluminum layer-titanium layer, and the third metal layer 8, that is, the composition of the upper electrode plate of the capacitor is a combination of one or more of a titanium layer, an aluminum layer and a copper layer. When the electrode plate of the capacitor contains an aluminum layer and a titanium layer, the unevenness problem caused by the stress release of the thick metal as an electrode can be alleviated, the internal stress caused by the change of the lattice during annealing can be alleviated, and the performance of the filter is optimized. In other embodiments, the composition of the upper electrode plate of the capacitor may be different from that of this embodiment.

[0065] In a specific embodiment, the thickness of the aluminum layer is less than or equal to 3 μm, the thickness of the titanium layer is less than or equal to 1 μm, the thickness of the first metal layer 6 is greater than or equal to 3 μm, and the thickness of the second metal layer 7 is greater than or equal to 3 μm.

[0066] In a specific embodiment, when the first metal layer 6 , the third metal layer 8 and the conductive structure 3 are all made of copper or other metals of the same type, the material consumption of the conductive structure 3 can be reduced without affecting the electrical connection.

[0067] In a specific embodiment, the first metal layer 6 and the second metal layer 7 are made of copper, and in other embodiments, they may be other metals; the first auxiliary layer 4, the second auxiliary layer and the third auxiliary layer are made of titanium, and in other embodiments, they may be titanium compounds, such as titanium nitride; the first insulating layer and the second insulating layer are made of polyimide, and in other embodiments, they may be one of phenolic resin, epoxy resin and other polymer materials; the third insulating layer 9 is made of silicon nitride, and in other embodiments, it may be one of silicon dioxide and other high dielectric constant materials; the third metal layer is a combination of one or more materials such as aluminum, titanium, copper, gold, silver, etc.; the conductive structure 3 is a metal wiring made of copper, and in other embodiments, it may be other metals. In other embodiments, the material of the composite metal layer may also be a combination of one or more materials of other submicron materials such as gold, silver, titanium, aluminum, copper, etc.

[0068] Figure 3 A schematic diagram of the three-dimensional structure of a filter with a composite metal layer is shown. Figure 3 As shown, it includes a glass substrate 1, a MIM capacitor, an inductor and a composite metal layer, the glass substrate 1 includes a first surface and a second surface arranged opposite to each other, and a plurality of glass through holes penetrating the glass substrate 1, the glass through holes are filled with metal to form a plurality of metal pillars 2, the first surface of the glass substrate 1 is provided with a composite metal layer, a first part of the inductor and the MIM capacitor, the second surface of the glass substrate 1 is provided with a second part of the inductor, the first part of the inductor includes a composite metal layer 5 and a first metal layer 6 connected to the composite metal layer 5, the second part of the inductor includes a second metal layer 7, the first part of the inductor, the metal pillar 2 and the second part of the inductor are connected in sequence The spiral conductor structure of the inductor is constituted, and the composite metal layer 5 of the inductor is located between the first metal layer 6 and the metal column 2. The area of ​​the composite metal layer 5 of the inductor is 1.3 times the cross-sectional area of ​​the metal column 2 on the first surface of the glass substrate 1. The composite metal layer 5 of this area can achieve a relatively excellent stress buffering effect. The MIM capacitor includes the composite metal layer 5. The composite metal 5 of the capacitor serves as the lower plate of the MIM capacitor and is connected to one of the metal columns 2 as the composite metal layer 5 of the metal column 2, avoiding waste of materials and space, alleviating the cracking effect caused by the metal column 2 squeezing the glass substrate 1, and preventing water vapor from entering the cracks, thereby reducing the reliability of the filter.

[0069] In a specific embodiment, the inductor and the capacitor are connected to a common metal block and use the same metal layer, thereby reducing the resistance value between the stacked layers and improving the Q value of the filter.

[0070] Figures 4 to 9 The stress simulation schematic diagram of the present application is shown. The stress simulation model is as follows Figure 4 and Figure 7 As shown, it includes a glass substrate 1, a metal column 2, a first auxiliary layer 4 and a first metal layer 6. In a specific embodiment, the material of the metal column 2 and the first metal layer 6 includes copper, the material of the first auxiliary layer 4 includes titanium, and the first auxiliary layer 4 is located between the first metal layer 6 and the glass substrate 1. Figure 7 The stress simulation model shown also includes a composite metal layer 5, which is located between the first auxiliary layer 4 and the glass substrate 1. The composite metal layer 5 includes an aluminum layer and a titanium layer. The corresponding cross-sectional schematic diagram of the glass substrate 1, the composite metal layer 5, the first metal layer 6 and the first auxiliary layer 4 is shown in FIG. Figure 8 As shown, the stress simulation model without the composite metal layer 5 is as shown in FIG. Figure 4 As shown, the cross-sectional schematic diagram of the corresponding glass substrate 1, the first metal layer 6 and the first auxiliary layer 4 is as shown Figure 5 In the simulation results, the schematic diagram of the principal stress distribution is shown in Figure 6 and Fig. 9 As shown, Figure 6 This is a schematic diagram of the principal stress distribution without the composite metal layer 5, and the maximum stress reaches 158.96Mpa. Fig. 9 It is a schematic diagram of the principal stress distribution with a composite metal layer 5, the maximum stress of which is 127.28Mpa, and the stress of the glass around the metal column 2 is significantly reduced. It should be noted that the schematic diagram of the principal stress distribution is a top-down perspective of the stress simulation model. In the stress simulation, the area of ​​the composite metal layer 5 is 2.4 times the area of ​​the metal column 2 on the first surface cross section of the glass substrate 1. This area ratio can achieve a better stress buffering effect, reduce interlayer separation caused by thick metal stress expansion, and improve the performance of the filter.

[0071] In a second aspect, the present application also proposes a method for manufacturing a filter. Figure 2 is a flow chart of a method for making a filter in a specific embodiment of the present application, such as Figure 2 As shown, the method comprises the following steps:

[0072] S1: forming a plurality of blind holes on the glass substrate 1;

[0073] S2: filling copper in the blind hole and forming a copper layer on the first surface of the glass substrate 1;

[0074] S3: removing the copper layer on the first surface of the glass substrate;

[0075] S4: preparing a composite metal layer and a MIM capacitor on the first surface of the glass substrate 1;

[0076] S5: preparing a first insulating layer, a first metal layer 6 and a conductive structure 3;

[0077] S6: preparing a second metal layer 7 on the second surface of the glass substrate 1 by temporary bonding;

[0078] S7: forming a second insulating layer on the second surface of the glass substrate 1;

[0079] S8: After debonding and wafer dicing, the complete filter structure is achieved.

[0080] The above-mentioned manufacturing method can be used to manufacture a filter, which avoids the circumferential stress caused by the metal pillar 2 squeezing the glass substrate 1 during the baking and stress process stages, thereby preventing the glass substrate 1 from cracking and entering water vapor, enhancing the wafer strength, and reducing the process cracking rate. At the same time, it alleviates the impact of internal stress caused by the change of the lattice of thick metal during annealing on the device, reduces the interlayer separation caused by the expansion of thick metal, ensures the excellent resonance performance of the filter, and is conducive to reducing particle contamination, reducing the defective rate, thereby improving the yield, reducing the impact of warping, and improving the film quality.

[0081] Optionally, the composite metal layer 5 includes a titanium layer and an aluminum layer, and S4 includes: preparing the titanium layer and the aluminum layer by a magnetron sputtering process. The composite metal layer 5 can alleviate the unevenness problem caused by the stress release of the thick metal as an electrode, and the composite metal layer 5, as part of the lower plate of the MIM capacitor, optimizes the performance of the filter.

[0082] In a specific embodiment, S1 further includes: forming a plurality of TGV blind holes on the glass substrate 1;

[0083] In a specific embodiment, S2 further includes: filling copper in the blind hole through an electroplating process and forming a copper layer on the first surface of the glass substrate 1 , and step S2 also includes baking.

[0084] In a specific embodiment, S3 further includes: removing the copper layer on the first surface of the glass substrate by chemical mechanical polishing;

[0085] In a specific embodiment, S4 also includes: preparing a composite metal layer on the first surface of the glass substrate 1, wherein the composite metal layer is a titanium layer prepared by a magnetron sputtering process, and the thickness of the titanium layer is less than or equal to 1 μm, and then preparing an aluminum layer by a magnetron sputtering process, and the thickness of the aluminum layer is less than or equal to 3 μm; depositing a third insulating layer 9 of the MIM capacitor to prepare a third metal layer 8, and then forming a composite metal layer 5 of the inductor and a MIM capacitor on the first surface of the glass substrate 1 by photolithography and dry etching, wherein the MIM capacitor includes the composite metal layer 5, and the composite metal layer covers the cross-section of the metal column 2 on the first surface of the glass substrate 1.

[0086] In a specific embodiment, S5 also includes: preparing a first insulating layer, preparing a first metal layer 6 and a portion of a conductive structure 3 by photolithography and electroplating, then performing pattern flattening to remove the copper layer on the surface of the first insulating layer, and then preparing the conductive structure 3 by photolithography and coating the first insulating layer, and reserving a notch on the first insulating layer for preparing solder balls. The material of the first metal layer 6 is copper, and the thickness of the first metal layer 6 is greater than or equal to 3μm. Step S5 also includes baking.

[0087] In a specific embodiment, S6 further includes: preparing solder balls, the solder balls connecting the conductive structures 3, forming through-glass vias in the glass substrate 1, and preparing a second metal layer 7 on the second surface of the glass substrate 1 by temporary bonding;

[0088] In a specific embodiment, S7 further includes: forming a second insulating layer on the second surface of the glass substrate 1. The material of the second metal layer 7 is copper, and the thickness of the second metal layer 7 is greater than or equal to 3 μm.

[0089] Optionally, the first insulating layer and the second insulating layer are made of polyimide, and in other embodiments may also be made of phenolic resin, epoxy resin and other polymer materials, and the conductive structure 3 is made of copper.

[0090] It should be noted that the force-bearing process refers to a process step including placing the wafer on a chuck for adsorption, at which time the product has multiple force points.

[0091] The structure and manufacturing method of a filter proposed in the present application, through the composite metal layer 5, reduce the circumferential stress caused by the metal column 2 squeezing the glass during the baking and stress process, enhance the wafer firmness, avoid the scrapping of cracks, and reduce the crack rate and cost of the process; at the same time, avoid the extension effect, which causes water vapor to enter the glass substrate 1, the inductor Q value deteriorates, and further affects the resonance performance of the filter, and also reduces the interlayer separation caused by the expansion of thick metal stress, thereby increasing the reliability of the filter; the composite metal layer 5 is used as a part of the lower plate of the capacitor, in which the aluminum layer and the titanium layer are prepared by the magnetron sputtering process, the flatness is improved, and the breakdown voltage of the capacitor is increased, The performance of the filter is optimized, and the composite metal layer 5 serves as the lower electrode of the MIM capacitor and is connected to one of the metal pillars 2 as the composite metal layer of the metal pillar 2, that is, the composite metal layer 5 serving as the lower electrode of the capacitor is connected to the composite metal layer 5 covering the metal pillar 2 on the first surface interface of the glass substrate 1, so as to realize a shared composite metal layer 5, avoid waste of materials and space, and reduce the unevenness problem caused by the stress release of the thick metal as an electrode. At the same time, an auxiliary metal layer is added, which can improve the adhesion and structural stability between materials, and at the same time help reduce the stress accumulation of the thick metal in the glass substrate, and maintain the stability of the inductor, capacitor and filter.

[0092] The above describes the specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A filter structure, characterized in that: include: A first insulating layer and a second insulating layer arranged opposite to each other, and a glass substrate located between the first insulating layer and the second insulating layer, wherein the glass substrate comprises a first surface and a second surface arranged opposite to each other, and the glass substrate has a plurality of glass through holes; at least one inductor, the inductor comprising a plurality of first portions located on the first surface of the glass substrate, a plurality of second portions located on the second surface of the glass substrate, and a plurality of metal pillars penetrating through-glass vias, the spiral conductor structure of the inductor being formed by connecting the first portion, the metal pillars, and the second portion of the inductor, the metal pillars connecting the first portion and the second portion of the inductor, the first portion of the inductor comprising a composite metal layer, the composite metal layer comprising a titanium layer and an aluminum layer; At least one capacitor, the capacitor comprising the composite metal layer.

2. A filter structure according to claim 1, characterized in that: Also included is a conductive structure connecting the first portion of the inductor and the capacitor.

3. A filter structure according to claim 2, characterized in that: The first part of the inductor includes a first metal layer between the glass substrate and the conductive structure, and the composite metal layer of the inductor corresponding to the metal column, the composite metal layer of the inductor is located between the first metal layer and the glass substrate, the composite metal layer of the inductor includes an aluminum layer between the first metal layer and the glass substrate, and a titanium layer between the aluminum layer and the glass substrate, and the second part of the inductor includes a second metal layer.

4. A filter structure according to claim 3, characterized in that: The metal column connects the composite metal layer of the inductor and the second part of the inductor, one metal column corresponds to one composite metal layer of the inductor, and the area of ​​the composite metal layer of the inductor is larger than the cross-sectional area of ​​the metal column on the glass substrate.

5. The structure of a filter according to claim 3, characterized in that: The capacitor includes a third insulating layer located between the glass substrate and the conductive structure, a composite metal layer located between the glass substrate and the third insulating layer, and a third metal layer located between the conductive structure and the third insulating layer. The composite metal layer of the capacitor includes an aluminum layer between the glass substrate and the third insulating layer, and a titanium layer between the glass substrate and the aluminum layer.

6. A filter structure according to claim 5, characterized in that: The composite metal layer of the capacitor is connected to one of the metal pillars of the inductor.

7. The filter structure according to claim 5, characterized in that: It also includes a first auxiliary layer between the first metal layer and the composite metal layer of the inductor, a second auxiliary layer between the metal column and the second metal layer, and a third auxiliary layer between the third insulating layer and the composite metal layer of the capacitor.

8. The filter structure according to claim 5, characterized in that: The thickness of the aluminum layer is less than or equal to 3 μm, the thickness of the titanium layer is less than or equal to 1 μm, the thickness of the first metal layer is greater than or equal to 3 μm, and the thickness of the second metal layer is greater than or equal to 3 μm.

9. A method for manufacturing a filter, characterized in that: The following steps are involved: S1: forming a plurality of blind holes on a glass substrate; S2: filling copper in the blind hole and forming a copper layer on the first surface of the glass substrate; S3: removing the copper layer on the first surface of the glass substrate; S4: preparing a composite metal layer and a MIM capacitor on the first surface of the glass substrate; S5: preparing a first insulating layer, a first metal layer and a conductive structure; S6: preparing a second metal layer on the second surface of the glass substrate by temporary bonding; S7: forming a second insulating layer on the second surface of the glass substrate; S8: After debonding and wafer dicing, the complete filter structure is achieved.

10. The method for manufacturing a filter according to claim 9, characterized in that: The composite metal layer includes a titanium layer and an aluminum layer, and S4 includes: preparing the titanium layer and the aluminum layer by a magnetron sputtering process.

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