Filter

Abstract

The utility model relates to the technical field of semiconductor devices, and particularly discloses a filter which comprises a substrate, a bulk acoustic wave resonator and a semiconductor cooler which are arranged in a stacked mode. The bulk acoustic wave resonator is arranged on the first surface of the substrate, the semiconductor refrigerator is provided with a refrigeration end surface, and the refrigeration end surface is in contact with the second surface of the substrate; and the first surface and the second surface are two opposite surfaces of the substrate. The heat dissipation performance of the device can be effectively improved, the reliability of the device is improved, the service life of the device is prolonged, and the power capacity of the filter is improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor devices, and in particular to a filter. Background Art

[0002] When a film bulk acoustic resonator (FBAR) filter is in operation, in addition to the conversion of mechanical energy and electrical energy, some of the energy will inevitably be converted into heat energy, causing the device to experience self-heating effects. This heat will become more pronounced as the frequency increases. Since the thickness of the piezoelectric material layer and the electrode layer is only at the micrometer or nanometer level, it is difficult for the heat to dissipate, causing the resonant frequency to shift, or stress accumulation to cause deformation of the material, thereby affecting the reliability and service life of the semiconductor device, and also limiting the power capacity of the filter. Existing technologies usually increase the power by increasing the area of ​​the FBAR and reducing the heat generated by the device. The disadvantage of this method is that it increases the area of ​​the filter, making it difficult to integrate the filter module. At the same time, the device does not have good heat dissipation performance and has limited power increase capabilities. Utility Model Content

[0003] The purpose of this application is to provide a filter that effectively improves the heat dissipation performance of the device, which not only improves the reliability and service life of the device, but also helps to improve the power capacity of the filter.

[0004] The embodiment of the present application is implemented as follows:

[0005] An embodiment of the present application provides a filter, comprising a stacked substrate, a bulk acoustic wave resonator, and a semiconductor cooler; the bulk acoustic wave resonator is arranged on a first surface of the substrate, the semiconductor cooler has a cooling end surface, and the cooling end surface is in contact with the second surface of the substrate; the first surface and the second surface are two opposite surfaces of the substrate.

[0006] As an optional implementation manner, the orthographic projection of the substrate in a direction perpendicular to the refrigeration end surface is located within the refrigeration end surface or coincides with the refrigeration end surface.

[0007] As an optional implementation, there are multiple BAW resonators, and the multiple BAW resonators are arrayed on the first surface of the substrate.

[0008] As an optional embodiment, the semiconductor refrigerator includes a hot end plate, a cold end plate and a thermocouple pair; the hot end plate and the cold end plate are arranged in parallel and spaced apart, and the thermocouple pair is arranged between the hot end plate and the cold end plate; the cooling end surface is located on the cold end plate and on the side away from the hot end plate.

[0009] As an optional implementation, the thermocouple pair includes a P-type structure, an N-type structure, and a metal bridge; the P-type structure and the N-type structure are arranged alternately, and the metal bridge connects the P-type structure and the N-type structure in series.

[0010] As an optional embodiment, the P-type structure and the N-type structure are both strip-shaped structural members whose extension direction intersects with the plane where the cold end plate is located, and the metal bridge includes an upper bridge connected in series with the first end of the adjacent strip-shaped structural members and in contact with the cold end plate, and a lower bridge connected in series with the second end of the adjacent strip-shaped structural members and in contact with the hot end plate.

[0011] As an optional embodiment, the extending direction of the strip structure is perpendicular to the plane where the cold end plate is located, so that a preset distance is generated between the cold end plate and the hot end plate.

[0012] As an optional embodiment, a side of the hot end plate facing away from the cold end plate is in contact with the external environment; or a radiator is provided on a side of the hot end plate facing away from the cold end plate.

[0013] As an optional implementation, in a direction perpendicular to the cold end plate, a projected edge of the hot end plate on the cold end plate coincides with an edge of the cold end plate.

[0014] As an optional embodiment, the semiconductor cooler further includes a power supply, which is electrically connected to the metal bridge and is used to supply direct current to the thermocouple pair.

[0015] The beneficial effects of the embodiments of the present application include:

[0016] The filter provided in the embodiment of the present application includes a stacked substrate, a bulk acoustic wave resonator, and a semiconductor cooler. The bulk acoustic wave resonator in the embodiment of the present application is arranged on the first surface of the substrate, and the semiconductor cooler has a cooling end surface, which contacts the second surface of the substrate. The first surface and the second surface of the embodiment of the present application are two opposite surfaces of the substrate. In the embodiment of the present application, the heat generated by the bulk acoustic wave resonator during operation is transferred to the cooling end surface through the substrate, and the cooling end surface of the semiconductor cooler is used to cool the substrate and the bulk acoustic wave resonator. Therefore, the filter provided in the embodiment of the present application has excellent heat dissipation performance.

[0017] Compared to existing technologies, the embodiments of the present application can significantly improve the power capacity of BAW resonators. They can quickly dissipate heat, preventing it from accumulating on the substrate, effectively preventing the resonant frequency from shifting due to high temperature, and addressing the problem of material deformation caused by stress buildup caused by high temperatures. Furthermore, the embodiments of the present application improve the device's heat dissipation performance without increasing the area of ​​the filter and BAW resonator, thereby not increasing the material cost per wafer and facilitating production cost control. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 This is one of the structural diagrams of the filter according to the embodiment of the present application;

[0020] Figure 2 This is the second structural diagram of the filter according to the embodiment of the present application;

[0021] Figure 3 This is the third structural diagram of the filter according to the embodiment of the present application.

[0022] Icons: 100-substrate; 101-bulk acoustic wave resonator; 102-semiconductor refrigerator; 103-first surface; 104-second surface; 105-hot end plate; 106-cold end plate; 107-thermocouple pair; 108-P-type structure; 109-N-type structure; 110-metal bridge; 111-strip structure; 112-upper bridge; 113-lower bridge; 114-power supply; 115-packaging structure; 116-filter chip. DETAILED DESCRIPTION

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0025] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. In addition, the terms "first," "second," "third," etc. are used only to distinguish the descriptions and are not to be understood as indicating or implying relative importance.

[0026] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0027] When a film bulk acoustic resonator (FBAR) filter is in operation, in addition to the conversion of mechanical energy and electrical energy, some of the energy will inevitably be converted into heat energy, causing the device to experience self-heating effects. This heat will become more pronounced as the frequency increases. Since the thickness of the piezoelectric material layer and the electrode layer is only at the micrometer or nanometer level, it is difficult for the heat to dissipate, causing the resonant frequency to shift, or stress accumulation to cause deformation of the material, thereby affecting the reliability and service life of the semiconductor device, and also limiting the power capacity of the filter. Existing technologies usually increase the power by increasing the area of ​​the FBAR and reducing the heat generated by the device. The disadvantage of this method is that it increases the area of ​​the filter, making it difficult to integrate the filter module. At the same time, the device does not have good heat dissipation performance and has limited power increase capabilities.

[0028] To solve the above technical problems, an embodiment of the present application provides a filter.

[0029] Reference Figure 1 、 Figure 2 As shown, an embodiment of the present application provides a filter, including a stacked substrate 100, a bulk acoustic wave resonator 101 and a semiconductor cooler 102; the bulk acoustic wave resonator 101 is arranged on a first surface 103 of the substrate 100, and the semiconductor cooler 102 has a cooling end surface, which is in contact with a second surface 104 of the substrate 100; the first surface 103 and the second surface 104 are two opposite surfaces of the substrate 100.

[0030] It should be noted that the existing technology usually reduces the power density by increasing the area of ​​the bulk acoustic wave resonator 101, thereby reducing the heat generated by the device to achieve the effect of increasing power. The disadvantage of this method is that it increases the coverage area of ​​the filter, which is not easy to integrate with the filter module. At the same time, the device does not have a good heat dissipation structure and the power increase capability is limited. In addition, as the device size increases, the average price per wafer will increase, thereby increasing the production cost of the device.

[0031] In this embodiment, a semiconductor cooler 102 is disposed on the side of the substrate 100 facing away from the BAW resonator 101 to cool the substrate 100 and prevent heat accumulation in the BAW resonator 101 during prolonged operation, which could lead to excessive temperature increases in the entire device. In other words, this embodiment improves heat dissipation by attaching the semiconductor cooler 102 to the substrate 100.

[0032] It should be noted that the substrate 100 of the embodiment of the present application is covered with a package housing that encloses the bulk acoustic wave resonator 101, and the package housing protects the internal filter chip 116. It should be noted that the filter chip 116 protected inside the package housing is provided with the FBAR 101.

[0033] The film bulk acoustic resonator (FBAR) 101 is a microelectronic device that uses the acoustic resonance effect of thin-film piezoelectric materials to achieve resonance at a specific frequency. It should be noted that the film bulk acoustic resonator 101 has a wide range of applications in the field of wireless communications due to its high Q value, wide bandgap effect, and good temperature stability.

[0034] Research on the power capacity of FBAR filters has been driven by market demand for high-power filters, such as those used in duplexers in wireless transceivers. FBARs in FBAR filters are primarily categorized into cavity-type, back-cavity-etched, and solid-state assembly types, depending on their structure and process.

[0035] Reference Figure 1 、 Figure 2 As shown, the filter provided in the embodiment of the present application includes a substrate 100, a bulk acoustic wave resonator 101 and a semiconductor cooler 102; the bulk acoustic wave resonator 101 in the embodiment of the present application is arranged on the first surface 103 of the substrate 100, and the semiconductor cooler 102 has a cooling end surface, which is in contact with the second surface 104 of the substrate 100; the first surface 103 and the second surface 104 in the embodiment of the present application are two opposite surfaces of the substrate 100.

[0036] It should be noted that the semiconductor cooler 102 in the embodiment of the present application is also called a Peltier cooler, which is a device that uses the Peltier effect of semiconductor materials to achieve cooling or heating.

[0037] The Peltier effect refers to the phenomenon of heat absorption or heat release at the junction of two dissimilar materials when current flows through the junction. In semiconductor cooler 102, when current flows through the semiconductor material, one end absorbs heat (the cooling end) while the other end releases heat (the hot end). By controlling the direction of the current, cooling or heating can be achieved.

[0038] In the embodiment of the present application, the heat generated by the BAW resonator 101 during operation is transferred to the cooling end surface through the substrate 100 , and the cooling end surface of the semiconductor cooler 102 is used to cool the substrate 100 and the BAW resonator 101 .

[0039] Therefore, the filter provided by the embodiments of the present application has excellent heat dissipation performance. Compared with the prior art, the embodiments of the present application can significantly improve the power capacity of the bulk acoustic wave resonator 101. The embodiments of the present application can quickly dissipate heat, prevent heat accumulation on the substrate 100, effectively prevent the resonant frequency from shifting due to high temperature, and solve the problem of material deformation caused by stress accumulation caused by high temperature.

[0040] In addition, the embodiment of the present application improves the heat dissipation performance of the device without increasing the area of ​​the filter and the BAW resonator 101 , thus not increasing the material cost of each wafer, which is beneficial to controlling production costs.

[0041] As an optional embodiment, a projected edge of the substrate 100 formed in a direction perpendicular to the cooling end surface is located within the cooling end surface or coincides with the cooling end surface.

[0042] It should be noted that the substrate 100 of the embodiment of the present application serves as a support structure for the bulk acoustic wave resonator 101, and silicon can be used as the material for the substrate 100. The projection of the substrate 100 formed along a direction perpendicular to the cooling end surface of the embodiment of the present application is located within the cooling end surface, that is, the area of ​​the substrate 100 of the embodiment of the present application is smaller than the area of ​​the cooling end surface.

[0043] More preferably, the projection edge of the substrate 100 formed in a direction perpendicular to the cooling end surface can be made to coincide with the cooling end surface. Compared with the above arrangement, the coincidence can effectively utilize the cooling end surface and avoid increasing the ineffective area on the cooling end surface.

[0044] Regarding the description of the ineffective area, if there is a portion on the cooling end surface that is not in contact with the second surface 104 of the substrate 100, it is defined as an ineffective area, and the smaller the area of ​​this area, the better.

[0045] To ensure that the entire second surface 104 of the substrate 100 can be cooled, the optimal configuration is to ensure that the projected edge of the substrate 100, perpendicular to the cooling end surface, coincides with the cooling end surface. In other words, the edges of the substrate 100 and the cooling end surface exactly overlap, achieving complete coverage of the substrate 100 while eliminating any ineffective areas.

[0046] As an optional implementation, there are multiple BAW resonators 101 , and the multiple BAW resonators 101 are arranged in an array on the first surface 103 of the substrate 100 .

[0047] It should be noted that the specific number of BAW resonators 101 can be set as needed by those skilled in the art and is not particularly limited. For example, there are three BAW resonators 101, and the three BAW resonators 101 are arranged in an array on the first surface 103 of the substrate 100. For example, there are five BAW resonators 101, and the three BAW resonators 101 are arranged in an array on the first surface 103 of the substrate 100.

[0048] It should be noted that the filter provided in the embodiments of the present application can also be used to form an integrated filter module. In this regard, those skilled in the art can configure it as needed.

[0049] For example, refer to Figure 3 As shown, a plurality of filter chips 116 with encapsulating housings are disposed above the substrate 100, and one or more semiconductor coolers 102 are disposed below the substrate 100. The cooling end surface of a semiconductor cooler 102 can correspond to multiple heat dissipating filter chips 116, or a one-to-one correspondence can be provided. That is, a plurality of filter chips 116 are arranged at intervals on the first surface 103 of the substrate 100, and a plurality of semiconductor coolers 102 are disposed on the second surface 104 of the substrate 100, with each semiconductor cooler 102 corresponding to each filter chip 116.

[0050] For example, four filter chips 116 are arranged at intervals on the first surface 103 of the substrate 100, and four semiconductor coolers 102 are arranged on the second surface 104 of the substrate 100, with the semiconductor coolers 102 corresponding to the filter chips 116. In this case, the cooling end surface of each semiconductor cooler 102 covers the projection of one filter chip 116 on the substrate 100 in the vertical direction.

[0051] For example, four filter chips 116 are arranged on the first surface 103 of the substrate 100 , and one semiconductor cooler 102 is arranged on the second surface 104 of the substrate 100 . In this case, the cooling end surface of one semiconductor cooler 102 completely covers the second surface 104 of the substrate 100 .

[0052] In the direction perpendicular to the cold end plate 106 , the projection edge of the hot end plate 105 on the cold end plate 106 coincides with the edge of the cold end plate 106 .

[0053] Reference Figure 1 、 Figure 2 As shown, as an optional embodiment, the semiconductor cooler 102 includes a hot end plate 105, a cold end plate 106 and a thermocouple pair 107; the hot end plate 105 and the cold end plate 106 are arranged in parallel and spaced apart, and the thermocouple pair 107 is arranged between the hot end plate 105 and the cold end plate 106; the cooling end surface is located on the cold end plate 106 and on the side away from the hot end plate 105.

[0054] The thermocouple pair 107 includes a P-type structure 108 , an N-type structure 109 and a metal bridge 110 . The P-type structures 108 and the N-type structures 109 are arranged alternately, and the metal bridge 110 connects the P-type structures 108 and the N-type structures 109 in series.

[0055] Furthermore, a packaging structure 115 is further provided on the outside of the semiconductor cooler 102 in the embodiment of the present application. A heat-conducting structure can be pre-embedded in the packaging structure 115 so that the heat on the hot end plate 105 can be conducted to the external environment.

[0056] Reference Figure 1 、 Figure 2 As shown, as an optional embodiment, the P-type structure 108 and the N-type structure 109 are both strip-shaped structural members 111 whose extension direction intersects with the plane where the cold end plate 106 is located, and the metal bridge 110 includes an upper bridge 112 that connects the first ends of adjacent strip-shaped structural members 111 in series and contacts the cold end plate 106, and a lower bridge 113 that connects the second ends of adjacent strip-shaped structural members 111 in series and contacts the hot end plate 105.

[0057] The semiconductor cooler 102 further includes a power supply 114 , which is electrically connected to the metal bridge 110 and is used to supply direct current to the thermocouple pair 107 .

[0058] Preferably, the extending direction of the strip structure 111 is perpendicular to the plane where the cold end plate 106 is located, so that a preset distance is generated between the cold end plate 106 and the hot end plate 105 .

[0059] It should be noted that, in the embodiment of the present application, the P-type structure 108 and the N-type structure 109 are arranged into a strip-shaped structural member 111, and the first ends of the adjacent P-type structures 108 and the N-type structures 109 are connected by an upper bridge 112. When power is applied, the upper bridge 112 forms a cold end, which reduces the temperature of the cold end plate 106 connected thereto, thereby cooling the substrate 100.

[0060] Conversely, the lower bridge 113 connects the second ends of the adjacent P-type structures 108 and N-type structures 109, forming a hot end when power is applied. It should be noted that in the embodiment of the present application, the strip-shaped structural member 111 formed by the P-type structures 108 and N-type structures 109 provides a predetermined spacing between the hot end plate 105 and the cold end plate 106, thereby preventing heat from the hot end plate 105 from affecting the BAW resonator 101 on the substrate 100.

[0061] As an optional embodiment, a side of the hot end plate 105 facing away from the cold end plate 106 is in contact with the external environment; or a radiator is provided on a side of the hot end plate 105 facing away from the cold end plate 106 .

[0062] Furthermore, the embodiment of the present application places the hot end plate 105 in contact with the external environment, so that the heat on the hot end plate 105 can quickly enter the external environment, avoiding accumulation on the device. More preferably, by providing a heat sink on the hot end plate 105, the heat dissipation performance can be enhanced.

[0063] It should be noted that the radiator can be a metal structural part with good thermal conductivity, and a cooling fan can be added as needed to improve the heat dissipation capacity, and there is no special limitation on this.

[0064] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A filter, characterized in that: The invention comprises a stacked substrate (100), a bulk acoustic wave resonator (101), and a semiconductor refrigerator (102); the bulk acoustic wave resonator (101) is arranged on a first surface (103) of the substrate (100); the semiconductor refrigerator (102) has a cooling end surface, and the cooling end surface is in contact with a second surface (104) of the substrate (100).

2. The filter according to claim 1, wherein The orthographic projection of the substrate (100) in a direction perpendicular to the refrigeration end surface is located within the refrigeration end surface or coincides with the refrigeration end surface.

3. The filter according to claim 1, wherein There are a plurality of bulk acoustic wave resonators (101), and the plurality of bulk acoustic wave resonators (101) are arrayed on the first surface (103) of the substrate (100).

4. The filter according to any one of claims 1 to 3, characterized in that The semiconductor refrigerator (102) comprises a hot end plate (105), a cold end plate (106) and a thermocouple pair (107); the hot end plate (105) and the cold end plate (106) are arranged in parallel and spaced apart, and the thermocouple pair (107) is arranged between the hot end plate (105) and the cold end plate (106); the cooling end surface is located on the cold end plate (106) and on the side away from the hot end plate (105).

5. The filter according to claim 4, characterized in that The thermocouple pair (107) includes a P-type structure (108), an N-type structure (109), and a metal bridge (110); the P-type structure (108) and the N-type structure (109) are arranged alternately, and the metal bridge (110) connects the P-type structure (108) and the N-type structure (109) in series.

6. The filter according to claim 5, characterized in that The P-type structure (108) and the N-type structure (109) are both strip-shaped structural members (111) whose extension direction intersects with the plane where the cold end plate (106) is located. The metal bridge (110) includes an upper bridge (112) connected in series with the first ends of adjacent strip-shaped structural members (111) and in contact with the cold end plate (106), and a lower bridge (113) connected in series with the second ends of adjacent strip-shaped structural members (111) and in contact with the hot end plate (105).

7. The filter according to claim 6, characterized in that The extending direction of the strip-shaped structural member (111) is perpendicular to the plane where the cold end plate (106) is located, so that a preset distance is generated between the cold end plate (106) and the hot end plate (105).

8. The filter according to claim 6, characterized in that A side of the hot end plate (105) facing away from the cold end plate (106) is in contact with the external environment; or a radiator is provided on a side of the hot end plate (105) facing away from the cold end plate (106).

9. The filter according to claim 5, characterized in that In a direction perpendicular to the cold end plate (106), a projected edge of the hot end plate (105) on the cold end plate (106) coincides with an edge of the cold end plate (106).

10. The filter according to any one of claims 5 to 9, characterized in that: The semiconductor cooler (102) further includes a power supply (114), which is electrically connected to the metal bridge (110) and is used to supply direct current to the thermocouple pair (107).

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