A filter, a radio frequency module and an electronic device
Patent Information
- Application Number
- CN202522578380.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-04
- Publication Date
- 2026-10-30
- Estimated Expiration
- 2035-12-04
AI Technical Summary
[0003]然而，现有IPD工艺制备的滤波器芯片，由于电感元件所需绕线空间较大，因此会占用电路基板较大的表贴面积，导致成本较高
[0023]相比于现有滤波器芯片采用IPD工艺将电感、电容集成在一起而占用电路基板较大的表贴面积，成本较高，本申请所提供的滤波器包括硅基芯片和电路基板，其中，硅基芯片集成有电容模块，电容模块包括至少一个电容元件，电路基板上设置有第一电感模块，第一电感模块包括至少一个第一电感元件，并且，硅基芯片焊接于电路基板上，使得电容模块与第一电感模块电性连接，组成滤波器电路结构；也就是说，滤波器的至少部分电感元件不再集成在硅基芯片中，而是绕制于电路基板上，并且，考虑到在电路基板设计中，滤波器周围基本不会设置其他电路，正好可以用于绕制电感元件，由此，本申请利用滤波器的硅基芯片在电路基板上的周围空间绕制滤波器的至少部分电感元件，以电路基板空间换取更小的硅基芯片空间，减小硅基芯片的电路规模，从而减小硅基芯片的尺寸，在保证滤波器性能的基础上，达到整体降低成本的目的。
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Figure CN224923701U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of radio frequency technology, and in particular to a filter, radio frequency module and electronic device. Background Technology
[0002] The primary function of a filter is to selectively allow signals within a specific frequency range to pass through while suppressing or attenuating other unwanted frequency components. It is widely used in wireless communication, radar, satellite systems, broadcasting, and other fields, and is a key component for ensuring signal quality and reducing interference. To meet the requirements of high frequency and high performance, filters used in radio frequency modules are generally fabricated using Integrated Passive Devices (IPD) technology. IPD technology integrates passive components such as inductors, capacitors, and resistors on a single silicon substrate, and the fabricated filter chip is then soldered onto a circuit board.
[0003] However, filter chips fabricated using existing IPD processes require a large amount of winding space for inductor components, which in turn occupies a large surface-mount area on the circuit board, resulting in higher costs. Utility Model Content
[0004] To address the aforementioned technical problems, this application provides a filter, an RF module, and an electronic device that reduce the size of the filter chip and effectively lower costs while ensuring filter performance.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] In a first aspect, this application provides a filter comprising:
[0007] A silicon-based chip, wherein the silicon-based chip integrates a capacitor module, and the capacitor module includes at least one capacitor element;
[0008] A circuit board, on which a first inductor module is disposed, the first inductor module including at least one first inductor element;
[0009] The silicon-based chip is soldered onto the circuit board, and the capacitor module is electrically connected to the first inductor module.
[0010] Optionally, the silicon-based chip also integrates a second inductor module, the second inductor module including at least one second inductor element, the inductance value of the second inductor element being less than the inductance value of the first inductor element;
[0011] The second inductor module is electrically connected to at least one of the capacitor module and the first inductor module.
[0012] Optionally, the inductance value of the second inductor is less than 0.2nH, and the inductance value of the first inductor is greater than or equal to 0.2nH.
[0013] Optionally, the circuit board includes a substrate and a first metal layer and a second metal layer stacked on the substrate, wherein the second metal layer is located on the side of the first metal layer opposite to the substrate;
[0014] The first inductor is located in the second metal layer.
[0015] Optionally, the silicon-based chip is soldered onto the circuit board using solder bumps or columnar bumps.
[0016] Optionally, the silicon-based chip integrates a first trace, and the circuit substrate has a second trace, the cross-sectional area of the second trace being larger than that of the first trace.
[0017] Optionally, the width of the second trace is greater than the width of the first trace;
[0018] And / or, the thickness of the metal layer where the second trace is located is greater than the thickness of the metal layer where the first trace is located.
[0019] Optionally, the linewidth of the first trace is less than or equal to 10 μm, and the thickness of the metal layer in which the first trace is located is less than or equal to 10 μm;
[0020] The linewidth of the second trace is greater than or equal to 30 μm, and the thickness of the metal layer in which the second trace is located is greater than or equal to 15 μm.
[0021] Secondly, this application provides a radio frequency module including any of the filters mentioned above.
[0022] Thirdly, this application provides an electronic device including the above-described radio frequency module or any of the above-described filters.
[0023] Compared to existing filter chips that use IPD technology to integrate inductors and capacitors, resulting in a large surface-mount area on the circuit board and higher costs, the filter provided in this application includes a silicon-based chip and a circuit board. The silicon-based chip integrates a capacitor module, which includes at least one capacitor element. A first inductor module, which includes at least one first inductor element, is disposed on the circuit board. The silicon-based chip is soldered onto the circuit board, so that the capacitor module and the first inductor module are electrically connected to form a filter circuit structure. In other words, at least some of the inductor elements of the filter are no longer integrated into the silicon-based chip, but are wound on the circuit board. Furthermore, considering that there are basically no other circuits around the filter in the circuit board design, it is perfect to use the space around the filter to wind the inductor elements. Thus, this application utilizes the space around the silicon-based chip of the filter on the circuit board to wind at least some of the inductor elements of the filter, exchanging the space of the circuit board for a smaller space for the silicon-based chip, reducing the circuit scale of the silicon-based chip, thereby reducing the size of the silicon-based chip, and achieving the goal of reducing the overall cost while ensuring the performance of the filter. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 This is a schematic cross-sectional view of a filter provided in an embodiment of this application.
[0026] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure of the filter shown;
[0027] Figure 3 for Figure 1 The diagram shows a top view of the filter's structure.
[0028] Figure 4 This is a schematic diagram of the circuit structure of a filter provided in an embodiment of this application;
[0029] Figure 5 This is a schematic diagram of the circuit structure of the circuit board portion of a filter provided in an embodiment of this application;
[0030] Explanation of reference numerals in the attached figures:
[0031] Silicon-based chip 100; circuit board 200; capacitor module 110; capacitor element 111; first inductor module 210; first inductor element 211; substrate 101; base 201; first metal layer M1; second metal layer M2; second trace S2. Detailed Implementation
[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0033] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.
[0034] As described in the background section, filter chips fabricated using existing IPD processes require a large amount of winding space for inductor components, which in turn occupies a large surface mount area on the circuit board, resulting in higher costs.
[0035] In view of this, embodiments of this application provide a filter. Figure 1 This illustration shows a cross-sectional structural diagram of a filter provided in an embodiment of this application. Figure 2 It shows Figure 1 The diagram shows the 3D structure of the filter. Figure 3 It shows Figure 1 The diagram shows a top view of the filter's structure, combined with... Figures 1-3 As shown, the filter provided in this embodiment includes a silicon-based chip 100 and a circuit board 200. The silicon-based chip 100 integrates a capacitor module 110, which includes at least one capacitor element 111. A first inductor module 210 is disposed on the circuit board 200, which includes at least one first inductor element 211. The silicon-based chip 100 is soldered onto the circuit board 200, so that the capacitor module 110 and the first inductor module 210 are electrically connected.
[0036] It should be noted that in silicon-based chips, the capacitance per unit area can be relatively large, thus the area corresponding to a capacitor of a certain capacitance value can be relatively small. Therefore, in the embodiments of this application, as... Figures 1-3 As shown, the capacitor module 110 of the filter is integrated into the silicon-based chip 100.
[0037] Meanwhile, considering that the winding space occupied by the inductor in an LC filter is larger than that occupied by the capacitor, and that other circuits are generally not placed around the filter in the circuit board design, it is perfectly suited for winding the inductor. Therefore, in the embodiments of this application, as... Figures 1-3 As shown, at least some of the inductor components of the filter are no longer integrated into the silicon-based chip 100, but are instead wound onto the circuit board 200.
[0038] Furthermore, the silicon-based chip 100 is flip-chip soldered onto the circuit board 200, thereby realizing the electrical connection between the capacitor module 110 and the first inductor module 210 to form a filter circuit structure.
[0039] To better understand this application, Figure 4 This paper shows a schematic diagram of the circuit structure of a filter provided in an embodiment of this application. Figure 5 This illustration shows a schematic diagram of the circuit structure of the circuit board portion of a filter provided in an embodiment of this application, in conjunction with... Figures 1-5 As shown, each capacitor element 111 in the capacitor module 110 of the filter is integrated in the silicon-based chip 100, which makes each capacitor element 111 not only high in performance, but also small in area and low in cost.
[0040] in, Figure 4 In the filter shown, capacitor module 110 includes seven capacitors: C1, C2, C3, C4, C5, C6, and C7, integrated into a silicon-based chip; the first inductor module 210 includes five inductors: L1, L2, L3, L4, and L5, disposed on a circuit board. The specific electrical connections of each component are as follows: Figure 4 As shown, no further details will be provided. Figure 5 In the filter shown, the silicon-based chip 100, including the capacitor module 110, has six pins from 1 to 6. It can be understood that the first inductor 211 in the first inductor module 210 is electrically connected to the pins of the silicon-based chip 100, thereby realizing the electrical connection between the first inductor 210 and the capacitor in the silicon-based chip 100.
[0041] Optionally, the silicon-based chip 100 can be fabricated using an integrated passive device (IPD) process. Since the IPD process uses micron / nanometer-level processing techniques on a single silicon substrate to create passive components with excellent performance, high precision, and small size, fabricating the silicon-based chip 100 using the IPD process results in capacitors with better performance. Alternatively, the silicon-based chip 100 can also be fabricated using a complementary metal-oxide-semiconductor (CMOS) process, depending on the specific circumstances.
[0042] It is understandable that, such as Figure 1 As shown, the silicon-based chip 100 includes a substrate 101 and a capacitor element 111 located on the substrate 101. The substrate 101 can be a silicon substrate or a silicon-on-insulator (SOI) substrate to obtain a capacitor element with better performance.
[0043] Therefore, compared to existing filter chips that use IPD technology to integrate inductors and capacitors together, which occupies a large surface-mount area on the circuit board and has a higher cost, the filter provided in this application embodiment does not integrate at least some inductor components into the silicon-based chip 100, but instead winds them onto the circuit board 200. Furthermore, considering that there are basically no other circuits around the filter in the circuit board design, it is perfect to use the space around the filter to wind inductor components. Thus, by using the space around the filter's silicon-based chip on the circuit board to wind at least some of the filter's inductor components, the space of the circuit board is exchanged for a smaller space for the silicon-based chip, reducing the circuit scale of the silicon-based chip, thereby reducing the size of the silicon-based chip. While ensuring the performance of the filter, the overall cost is reduced.
[0044] Optionally, in some embodiments of this application, the first inductor module 210 includes all the inductor elements of the filter, that is, all the inductor elements of the filter can be wound on the circuit board. In this way, the circuit scale of the silicon-based chip can be further reduced, thereby further reducing the size of the silicon-based chip and further reducing the cost.
[0045] Optionally, in some other embodiments of this application, considering that the silicon-based chip 100 may be soldered to the circuit board 200 to achieve electrical connection, which may cause parasitics and affect the performance of inductors with smaller inductance values, it is also possible to place only the inductors with larger inductance values and larger winding space required in the filter on the circuit board, while integrating the inductors with smaller inductance values and smaller winding space required in the filter into the silicon-based chip 100.
[0046] In other words, in addition to integrating a capacitor module 110 including a capacitor element 111, the silicon-based chip 100 also integrates a second inductor module. The second inductor module includes at least one second inductor element, and the inductance value of the second inductor element is smaller than the inductance value of the first inductor element 211. As a result, the parasitic influence of the bonding portion between the silicon-based chip 100 and the circuit board 200 on the inductor with the smaller inductance value is reduced, ensuring the performance of the filter. At the same time, the integration of the inductor with the smaller inductance value into the silicon-based chip 100 will not have a significant impact on the size of the silicon-based chip 100, that is, the size of the silicon-based chip 100 remains relatively small, and the overall cost of the filter is relatively low.
[0047] It is understood that the second inductor module is electrically connected to at least one of the capacitor module 110 and the first inductor module 210 to form a filter circuit structure. Specifically, the second inductor module can be electrically connected to the capacitor module 110 within the silicon-based chip 100, and the second inductor module can be electrically connected to the first inductor module 210 through soldering between the silicon-based chip 100 and the circuit board 200.
[0048] Optionally, considering that the parasitics generated at the welding point between the silicon chip 100 and the circuit board 200 may have a significant impact on small inductors below 0.2nH, the inductance value of the second inductor can be set to be less than 0.2nH, and the inductance value of the first inductor 211 can be greater than or equal to 0.2nH. That is, inductors with an inductance value greater than or equal to 0.2nH in the filter are wound on the circuit board 200, while inductors with an inductance value less than 0.2nH in the filter are integrated into the silicon chip 100. This reduces the impact of parasitics generated at the welding point between the silicon chip 100 and the circuit board 200 on inductors below 0.2nH, ensuring the performance of the filter. At the same time, integrating inductors below 0.2nH into the silicon chip 100 will not significantly affect the size of the silicon chip 100, meaning the size of the silicon chip 100 remains relatively small, and the overall cost of the filter is relatively low, balancing the performance and cost of the filter.
[0049] Optionally, in some embodiments of this application, such as Figures 1-3As shown, the circuit board 200 includes a substrate 201 and a first metal layer M1 and a second metal layer M2 stacked on the substrate 201. The second metal layer M2 is located on the side of the first metal layer M1 away from the substrate 201. The inductor (i.e., the first inductor 211) wound on the circuit board 200 in the filter can be disposed on the second metal layer M2. The second metal layer M2 can be the top metal layer. In this way, it is not only convenient to connect the first inductor module 210 in the circuit board 200 with the capacitor module 110 in the silicon chip 100, but also, considering that the bottom metal layer of the circuit board 200 is usually grounded, the inductor of the filter is wound on the second metal layer M2, which is relatively far away from the bottom metal layer of the circuit board 200. This makes the inductor wound on the circuit board 200 relatively far away from the grounded metal layer, thereby making the performance of the inductor wound on the circuit board 200 better and improving the Q value of the filter.
[0050] It should be noted that this application does not limit the number of metal layers in the circuit board 200, and it can include two or more metal layers, depending on the specific circumstances.
[0051] Regarding the welding method between the silicon-based chip 100 and the circuit board 200, optionally, in some embodiments of this application, such as... Figure 1 As shown, the silicon-based chip 100 can be soldered to the circuit board 200 via a pillar bump T1. The pillar bump T1 includes a copper pillar and a solderable material (such as a tin alloy) located on the top of the copper pillar. Since the copper pillar provides stable support and efficient electrical and thermal conduction, the solderable material applied to the top of the copper pillar melts when heated, thereby firmly soldering the silicon-based chip 100 to the circuit board 200.
[0052] Alternatively, the silicon-based chip 100 can also be soldered onto the circuit board 200 using conventional solder bumps.
[0053] Compared to traditional solder bumps, using pillar bumps to solder the silicon-based chip 100 and the circuit board 200 is advantageous because copper pillars are less prone to deformation and collapse during soldering, thus supporting fine circuit connections. Furthermore, copper pillars maintain a fixed height better, providing higher stability and reliability. Additionally, copper pillars are good conductors of heat, so using pillar bumps can also reduce resistance and improve the electrical and heat dissipation performance of the filter.
[0054] For filter chips fabricated using existing IPD processes, there is a problem: the small cross-sectional area of the internal traces limits the filter's fusing power. However, using traces with larger cross-sectional areas would increase the chip size. Therefore, the filter provided in this application, in addition to winding at least some inductor elements on the circuit board 200, can further have traces set on the circuit board 200. Compared to the internal traces of the silicon-based chip 100, the traces on the circuit board 200 can have a larger cross-sectional area and relatively lower precision, thereby achieving better current carrying capacity and improving the filter's power handling capability.
[0055] Accordingly, in some embodiments of this application, such as Figures 1-3 As shown, the silicon-based chip 100 integrates a first trace, and the circuit board 200 is provided with a second trace S2. The cross-sectional area of the second trace S2 is larger than that of the first trace, thereby obtaining better current carrying capacity and improving the power handling capacity of the filter.
[0056] Optionally, the line width of the second trace S2 on the circuit board 200 can be set to be greater than the line width of the first trace on the silicon chip 100, so that the cross-sectional area of the second trace S2 is greater than the cross-sectional area of the first trace.
[0057] Alternatively, the thickness of the metal layer on the circuit board 200 where the second trace S2 is located can be set to be greater than the thickness of the metal layer on the silicon chip 100 where the first trace is located, so that the cross-sectional area of the second trace S2 is greater than the cross-sectional area of the first trace.
[0058] Alternatively, the linewidth of the second trace S2 on the circuit board 200 can be set to be greater than the linewidth of the first trace on the silicon chip 100, and the thickness of the metal layer on the circuit board 200 where the second trace S2 is located can be set to be greater than the thickness of the metal layer on the silicon chip 100 where the first trace is located, so that the cross-sectional area of the second trace S2 is greater than the cross-sectional area of the first trace.
[0059] Specifically, in some embodiments of this application, the linewidth of the first trace on the silicon-based chip 100 is less than or equal to 10 μm, and the thickness of the metal layer on which the first trace is located is less than or equal to 10 μm; the linewidth of the second trace S2 on the circuit board 200 is greater than or equal to 30 μm, and the thickness of the metal layer on which the second trace S2 is located is greater than or equal to 15 μm; thereby making the cross-sectional area of the second trace S2 larger than that of the first trace, thereby enabling the filter to obtain better current carrying capacity and improve the power handling capacity of the filter.
[0060] In summary, the filter provided in this application integrates the filter's capacitor elements onto a silicon-based chip and winds at least a portion of the filter's inductor elements onto a circuit board to achieve the filter's circuit structure. By utilizing the space surrounding the silicon-based chip on the circuit board to wind at least a portion of the filter's inductor elements, the space on the circuit board is exchanged for a smaller silicon-based chip space, reducing the circuit scale of the silicon-based chip and thus its size. This achieves overall cost reduction while maintaining filter performance. Furthermore, larger cross-sectional area and relatively lower precision traces can be provided on the circuit board to realize internal electrical connections of the filter, thereby obtaining better current carrying capacity and improving the filter's power handling capability.
[0061] Accordingly, this application also provides a radio frequency module, which includes the filter provided in any of the above embodiments.
[0062] This application also provides an electronic device, which includes the radio frequency module described above, or the filter provided in any of the above embodiments.
[0063] Since the filters have been described in detail in the foregoing embodiments, please refer to the foregoing embodiments; they will not be repeated here.
[0064] This electronic device can be used in all devices that require filters as components, such as duplexers and other electronic products that use these components.
[0065] The various parts of this manual are described in a combination of parallel and progressive methods. Each part focuses on the differences between the other parts, and the same or similar parts can be referred to each other.
[0066] The features described above regarding the disclosed embodiments can be substituted or combined with each other to enable those skilled in the art to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A filter, characterized in that, include: A silicon-based chip, wherein the silicon-based chip integrates a capacitor module, and the capacitor module includes at least one capacitor element; A circuit board, on which a first inductor module is disposed, the first inductor module including at least one first inductor element; The silicon-based chip is soldered onto the circuit board, and the capacitor module is electrically connected to the first inductor module.
2. The filter according to claim 1, characterized in that, The silicon-based chip also integrates a second inductor module, which includes at least one second inductor element, the inductance value of which is less than the inductance value of the first inductor element. The second inductor module is electrically connected to at least one of the capacitor module and the first inductor module.
3. The filter according to claim 2, characterized in that, The inductance value of the second inductor is less than 0.2nH, and the inductance value of the first inductor is greater than or equal to 0.2nH.
4. The filter according to claim 1, characterized in that, The circuit board includes a substrate and a first metal layer and a second metal layer stacked on the substrate, wherein the second metal layer is located on the side of the first metal layer opposite to the substrate; The first inductor is located in the second metal layer.
5. The filter according to claim 1, characterized in that, The silicon-based chip is soldered onto the circuit board via solder bumps or columnar bumps.
6. The filter according to claim 1, characterized in that, The silicon-based chip has a first trace integrated on it, and the circuit board has a second trace, the cross-sectional area of the second trace being larger than that of the first trace.
7. The filter according to claim 6, characterized in that, The width of the second trace is greater than the width of the first trace; And / or, the thickness of the metal layer where the second trace is located is greater than the thickness of the metal layer where the first trace is located.
8. The filter according to claim 6, characterized in that, The linewidth of the first trace is less than or equal to 10 μm, and the thickness of the metal layer containing the first trace is less than or equal to 10 μm. The linewidth of the second trace is greater than or equal to 30 μm, and the thickness of the metal layer in which the second trace is located is greater than or equal to 15 μm.
9. A radio frequency module, characterized in that, Includes the filter described in any one of claims 1-8.
10. An electronic device, characterized in that, It includes the radio frequency module as described in claim 9, or the filter as described in any one of claims 1-8.