Ceramic Encapsulation Tube Structure and Components

Abstract

This invention discloses a ceramic package structure and assembly. The ceramic package structure includes a base and a filter disposed within the base. An internal cavity is formed in the middle of the base, including a chip cavity. The chip cavity includes a first end portion, on which a first connection cavity is formed. The filter is located between the internal cavity and the first connection cavity, with one end of the filter disposed on the first connection cavity and the other end disposed on a step in the chip cavity, thereby enabling the chip packaged within the package to connect with an external circuit. This invention discloses a ceramic package structure and assembly that integrates the filter internally within the base, located between the internal cavity and the first connection cavity, achieving connection between the chip and an external circuit. This eliminates the need for additional design and installation of an external filter, significantly improving the integration density of the package, while shortening the connection path between the filter and the chip / external circuit, reducing losses and discontinuities during high-frequency signal transmission.

Description

Technical Field

[0001] This invention relates to the field of electronic packaging technology, and more particularly to ceramic packaging shell structures and components. Background Technology

[0002] With the development of wireless technology, the operating frequency of devices is getting higher and higher. Systems such as 5G communication, satellite communication, and high-precision radar have already used millimeter wave frequency bands for signal transmission, and the system's demand for integration density is also increasing.

[0003] Faced with increasingly complex network systems, traditional packaging forms with single functions and simple structures no longer meet the requirements. Although low temperature co-fired ceramic (LTCC) technology can be stacked in three dimensions, it still has the disadvantages of low integration density, difficulty in designing and processing complex external circuits, discontinuity in high frequency signal transmission, and difficulty in handling heat dissipation of high power chips. Summary of the Invention

[0004] The purpose of this invention is to provide a ceramic package structure and assembly. By embedding the filter inside the base, the connection between the chip and external circuits is achieved, increasing the integration density of the package and reducing losses and discontinuities during high-frequency signal transmission. The specific technical solution is as follows: A ceramic encapsulation shell structure includes a base and a filter disposed within the base. The base has an internal cavity in the middle, the internal cavity including a chip cavity. The base includes a first end, on which a first connection cavity is disposed. The filter is located between the internal cavity and the first connection cavity. One end of the filter is disposed on the first connection cavity, and the other end is disposed on a step in the chip cavity, so that the chip encapsulated in the shell can be connected to an external circuit.

[0005] Furthermore, it also includes a first ground conductive layer and a second ground conductive layer. The filter includes multiple resonators and a second conductive post disposed between the multiple resonators. The two ends of the second conductive post are respectively connected to the first ground conductive layer and the second ground conductive layer. The resonator includes a first conductive post and a first conductive strip. The two ends of the first conductive post are respectively connected to the first ground conductive layer and the first conductive strip.

[0006] Furthermore, it also includes a second conductive strip, and the number of resonators is set to three, which are arranged in a triangle, and the three first conductive pillars are connected through the second conductive strip.

[0007] Furthermore, it also includes a high-frequency adapter structure. The base also includes a second end corresponding to the first end. A second connection cavity is provided on the second end. The high-frequency adapter structure includes a vertically arranged third conductive post and a horizontally arranged third conductive strip. The third conductive post and the third conductive strip are connected. One end of the high-frequency adapter structure is provided on the step of the second connection cavity, and the other end is provided on the step of the chip cavity for connecting the chip.

[0008] Furthermore, a PCB cavity is provided below the second connecting cavity, and the area of ​​the second connecting cavity is larger than the area of ​​the PCB cavity.

[0009] Furthermore, it also includes a low-frequency transmission structure. The base also includes a corresponding third end and a fourth end, each with a third connection cavity. The low-frequency transmission structure includes a vertically arranged fourth conductive post and a horizontally arranged fourth conductive strip. The fourth conductive post and the fourth conductive strip are connected. One end of the low-frequency transmission structure is set on the step of the third connection cavity for connecting to an external circuit, and the other end is set on the step of the chip cavity for connecting to a chip.

[0010] Furthermore, it also includes several grounding conductive layers and several grounding conductive posts connected together, with the grounding conductive layers and grounding conductive posts located outside the high-frequency switching structure.

[0011] Furthermore, it also includes a cover plate and a heat conductor. The internal cavity also includes an air cavity disposed above the chip cavity, and an upper heat conductor cavity and a lower heat conductor cavity disposed below the chip cavity. The internal cavity is through the direction of the line connecting the air cavity and the lower heat conductor cavity. The area of ​​the air cavity is larger than the area of ​​the chip cavity, the area of ​​the chip cavity is not less than the area of ​​the upper heat conductor cavity, and the area of ​​the upper heat conductor cavity is larger than the area of ​​the lower heat conductor cavity. The cover plate is disposed above the air cavity, and the heat conductor is disposed inside the upper heat conductor cavity and the lower heat conductor cavity.

[0012] A ceramic encapsulation housing assembly includes the aforementioned ceramic encapsulation housing structure and a chip, wherein the chip is disposed within a chip cavity, and the distance between the step of the chip cavity and the top surface of the chip is less than 0.3 mm.

[0013] Furthermore, it also includes a PCB board disposed within the PCB cavity, wherein the distance between the top surface of the PCB board and the bottom of the second connecting cavity is less than 0.3 mm.

[0014] The ceramic encapsulation shell structure and assembly of the present invention have the following advantages: 1. By embedding the filter inside the base and placing it between the internal cavity and the first connection cavity, the chip is connected to the external circuit. This eliminates the need for additional design and installation of the external filter, significantly increasing the integration density of the package. At the same time, it shortens the connection path between the filter and the chip and the external circuit, reducing losses and discontinuities in the high-frequency signal transmission process.

[0015] 2. By optimizing the filter structure and using the precise connection between the conductive pillars and the ground conductive layer, a stable resonant foundation is formed, and the resonant coupling characteristics are optimized through the second conductive pillar between the resonators, achieving precise frequency selection of high-frequency signals. At the same time, the ground conductive layer can shield external interference and confine internal signals, further reducing signal transmission loss and ensuring the stability of filtering performance.

[0016] 3. By arranging the three resonators in a triangular configuration and connecting the three first conductive pillars with a second conductive strip, a third-order filter is formed, which improves the spatial coupling efficiency of the resonant unit. The second conductive strip also enhances the continuity of signal transmission between the resonant units. This structure further improves the packaging integration while simplifying the filter structure by relying on the protection of the ground conductive layer.

[0017] 4. The high-frequency conversion structure adopts a combination of a vertically arranged third conductive post and a horizontally arranged third conductive strip to achieve interconnection between vertical and horizontal spaces, which can effectively avoid structural interference areas on the two-dimensional plane; at the same time, through the step connection between the second connecting cavity at the second end of the base and the chip cavity, a dedicated high-frequency signal transmission channel is constructed, which can stably realize the conversion of complex high-frequency signals between the chip and external circuits.

[0018] 5. A PCB cavity is set below the second connecting cavity, and the area of ​​the second connecting cavity is larger than the area of ​​the PCB cavity. On the one hand, the PCB board can be placed compactly in the PCB cavity, avoiding deep gaps between the casing and the external circuit in the vertical direction, and reducing the discontinuity of high-frequency signal transmission. On the other hand, the larger area of ​​the second connecting cavity can provide sufficient horizontal space for the end arrangement of the high-frequency adapter structure, while reserving sufficient bonding operation margin to ensure stable and reliable bonding connection between the high-frequency adapter structure and the PCB board.

[0019] 6. By setting a third connection cavity in the base and configuring a low-frequency transmission structure composed of a fourth conductive post and a fourth conductive strip, a dedicated current and control signal transmission channel is provided for the chip, realizing the separation of low-frequency signals from high-frequency signals and filtered signals, with clear division of labor and stronger adaptability. Attached Figure Description

[0020] Figure 1 This is an exploded view of the ceramic encapsulation tube and shell assembly of the present invention.

[0021] Figure 2 This is a top view of the ceramic encapsulation tube assembly of the present invention.

[0022] Figure 3 This is a longitudinal sectional view of the ceramic encapsulation tube assembly of the present invention.

[0023] Figure 4This is a top view of the ceramic encapsulation shell structure of the present invention.

[0024] Figure 5 This is a schematic diagram of the internal cavity and the external cavity in the ceramic encapsulation shell structure of the present invention.

[0025] Figure 6 These are top and three-dimensional comparison views of the filter in the ceramic encapsulation shell structure of this invention.

[0026] Figure 7 These are top and three-dimensional comparison views of the high-frequency switching structure in the ceramic encapsulation shell structure of this invention.

[0027] Figure 8 These are top and three-dimensional comparison views of the low-frequency transmission structure in the ceramic encapsulation shell structure of this invention.

[0028] Figure 9 This is a circuit diagram of the ceramic encapsulation housing assembly of the present invention.

[0029] Figure 10 This is a side cross-sectional view of the heat conductor in the ceramic encapsulation shell structure of the present invention. Detailed Implementation

[0030] like Figures 1 to 10 As shown, the present invention provides a ceramic encapsulation shell structure, including a base 1. The base 1 is made of several layers of ceramic dielectric, conductive layers printed on the surface of the dielectric, and conductive pillars that pass through the dielectric layers and connect different conductive layers, and is processed by LTCC three-dimensional multilayer stacking technology. The base 1 includes a dielectric body that plays a supporting role and a conductor network that connects external circuits and internal chipsets.

[0031] The base 1 has multiple stepped cavities around its outer perimeter and inside. Its dielectric body is formed by stacking several layers of ceramic dielectric using LTCC technology. The conductor network consists of conductive layers attached to the surfaces of the several ceramic dielectric layers and conductive pillars that pass through the several ceramic dielectric layers to connect different conductive layers. This conductor network includes a filter 13 that performs frequency selection, a high-frequency switching structure that transmits radio frequency signals, a low-frequency transmission structure that provides current and control signals to the internal chip 3, and a grounding conductive structure that shields external interference and confines internal signals.

[0032] like Figure 3 and Figure 5As shown, the base 1 has a thin plate-like structure. The stepped cavity includes an outer cavity open at the top and the outside, and an inner cavity open at both the top and the bottom. The outer cavity is used to connect external circuits and support the PCB board. The inner cavity includes an air cavity 8, a chip cavity 9, an upper heat conductor cavity 10, and a lower heat conductor cavity 11 arranged sequentially from top to bottom. The inner cavity is through the line connecting the air cavity 8 and the lower heat conductor cavity 11. The area of ​​the air cavity 8 is larger than the area of ​​the chip cavity 9, the area of ​​the chip cavity 9 is not smaller than the area of ​​the upper heat conductor cavity 10, and the area of ​​the upper heat conductor cavity 10 is larger than the area of ​​the lower heat conductor cavity 11, thus forming a stepped cavity structure. A cover plate 4 is provided above the air cavity 8. Heat conductors 2 are provided in the upper heat conductor cavity 10 and the lower heat conductor cavity 11 to seal the chip cavity 9 and the air cavity 8.

[0033] It is understandable that if the heat generated by chip 3 is relatively small, a heat conductor may not be required. Those skilled in the art can make this choice based on the actual situation.

[0034] Specifically, in this embodiment, four internal cavities are arranged sequentially along the horizontal direction. The direction perpendicular to the horizontal direction is defined as the longitudinal direction. The base 1 has a first end 5 and a second end 6 in the longitudinal direction. The outer cavity on the first end 5 includes four first connecting cavities 7. The filter 13 is located between the internal cavity and the first connecting cavity 7. The horizontal area in the stepped cavity that connects to the top of each cavity is defined as the step of the cavity. One end of the filter 13 is set on the step of the first connecting cavity 7 and is connected to the external circuit by bonding or soldering. The other end of the filter 13 is set on the step of the chip cavity 9 near the first end 5 and is used for bonding to the chip 3. Thus, by means of the spatial partitioning and embedded integration of the base 1, the filter 13 can match the signal transmission requirements of multiple chips 3. Frequency selection is achieved by the filter 13 that independently corresponds to the four internal cavities. At the same time, the additional design of the external filter 13 is eliminated, thereby improving the integration of the package shell, shortening the connection path between the filter 13 and the external circuit and chip 3, and reducing high-frequency signal transmission loss and discontinuity.

[0035] It should be noted that the grounding conductive structure consists of several grounding conductive layers and several grounding conductive posts connected together, and is then connected to the external ground through the grounding conductive layer on the surface of the base 1. The grounding conductive structure includes a first grounding conductive layer 14 and a second grounding conductive layer 15 disposed in the base 1.

[0036] Furthermore, such as Figure 6As shown, the filter 13 includes multiple resonators, with a second conductive post 16 disposed between the multiple resonators. The two ends of the second conductive post 16 are respectively connected to the first ground conductive layer 14 and the second ground conductive layer 15. The resonator includes a first conductive post 17 and a first conductive strip 18. The first conductive strip 18 is located between the first ground conductive layer 14 and the second ground conductive layer 15. The two ends of the first conductive post 17 are respectively connected to the first ground conductive layer 14 and the first conductive strip 18. The purpose of this structure is to form a resonant foundation by connecting one end of the first conductive post 17 to the first ground conductive layer 14 and the other end to the first conductive strip 18, and then optimize the resonant coupling characteristics by connecting the two ends of the second conductive post 16 between the resonators to the first ground conductive layer 14 and the second ground conductive layer 15 respectively, and achieve accurate frequency selection by means of the synergistic effect of multiple resonant units.

[0037] Furthermore, the filter 13 also includes two second conductive strips 19 disposed between the first ground conductive layer 14 and the first conductive strip 18. The number of resonators is set to three, which are arranged in a triangular pattern in the horizontal plane. Two first conductive posts 17 are connected to the other first conductive post 17 through one of the second conductive strips 19, thus forming a third-order filter 13. The triangular arrangement improves the spatial coupling efficiency of the resonant units, the second conductive strips 19 enhance the coherence of signal transmission between units, and the grounding characteristics of the first ground conductive layer 14 ensure the stability of the filter. This not only enhances the structural integration, but also relies on the ground conductive layer to shield external interference and confine internal signals, reducing signal transmission loss and structural design complexity.

[0038] Preferably, the outer cavity further includes eight second connecting cavities 20 disposed on the second end 6. A PCB cavity 21 is disposed below the second connecting cavity 20 for placing the PCB board, so as to avoid deep gaps between the casing and the external circuit in the vertical direction and reduce the discontinuity of high-frequency signal transmission. The area of ​​the second connecting cavity 20 is larger than the area of ​​the PCB cavity 21, so that the step of the second connecting cavity 20 has a wider horizontal space, which can accommodate the end arrangement of the high-frequency signal transition structure, and at the same time provide sufficient operating margin for bonding operations, ensuring a stable and reliable bonding connection between the transition structure and the PCB board.

[0039] like Figure 7As shown, the high-frequency signal conversion structure consists of several vertically arranged third conductive posts 22 and horizontally arranged third conductive strips 23. Vertical interconnection is achieved through the third conductive posts 22, and horizontal interconnection is achieved through the third conductive strips 23, thus avoiding interference between the two-dimensional planes and realizing a complex signal conversion network. One end of the high-frequency conversion structure is set on the step of the connecting cavity and connected to the PCB board placed in the PCB cavity 21 via bonding. The other end is set on the step near the second end 6 of the chip cavity 9 and connected to the chip 3 via bonding. It can be understood that the interconnection between the third conductive strips 23 and the third conductive posts 22 also includes the case where the connection between the PCB board and the chip 3 can be achieved solely by the third conductive strips 23.

[0040] It is understood that the dimensions of the aforementioned conductive strips and conductive pillars are related to the characteristic impedance, and those skilled in the art can fine-tune the impedance matching by changing the local dimensions.

[0041] It should be noted that the grounding conductive layer and grounding conductive post are located outside the high-frequency switching structure. Consequently, the high-frequency switching structure is constrained by the surrounding grounding conductive structure, forming an enclosed structure. The high-frequency switching structure and the surrounding grounding conductive structure are not connected. Together, they constitute a microwave transmission structure. Therefore, the high-frequency switching structure has strict impedance matching requirements. Those skilled in the art can determine the diameter of the conductive post, the width of the conductive strip, and the specific distance between the high-frequency switching structure and the surrounding grounding conductive structure through electromagnetic simulation to ensure normal signal transmission.

[0042] Preferred, such as Figure 8 As shown, the base 1 has a third end 24 and a fourth end 25 in the lateral direction. The outer cavity also includes a third connecting cavity 26 respectively disposed on the third end 24 and the fourth end 25. The low-frequency transmission structure includes a plurality of vertically arranged fourth conductive posts 27 and a plurality of horizontally arranged fourth conductive strips 28. The two ends of the low-frequency transmission structure are connected to the fourth conductive strips 28 through the fourth conductive posts 27. External ports 29 are disposed on the fourth conductive posts 27 near the two ends of the low-frequency transmission structure, and internal ports are disposed on the fourth conductive posts 27 in the middle. The external ports 29 are disposed on the steps of the third connecting cavity 26 and are connected to the external circuit by bonding. The internal ports are disposed on the steps on both sides of the chip cavity 9 and are connected to the chip 3 by bonding. The low-frequency transmission structure is not connected to the grounding conductive structure.

[0043] The low-frequency transmission structure is used to provide current and control signals to the internal chip 3, so there is no impedance matching requirement. As long as the linewidth of the conductive strip and the diameter of the conductive pillar meet the power and process requirements, it is acceptable.

[0044] Preferably, such as Figure 10As shown, the heat conductor 2 is a solid structure with a larger upper part and a smaller lower part. Its longitudinal section is T-shaped and it is made of a high thermal conductivity material, preferably a metal such as copper, molybdenum, or kova alloy. Alternatively, a non-metallic high thermal conductivity material such as aluminum nitride or graphite can be used. The heat conductor 2 is embedded in the cavity of the base 1. The upper part is embedded in the upper heat conductor cavity 10 of the medium body and connected to the steps of the upper heat conductor cavity 10 and the lower heat conductor cavity 11. The connection method is bonding or welding. The lower part is embedded in the lower heat conductor cavity 11 of the medium body, and the bottom plane of the heat conductor 2 is flush with the bottom of the base 1.

[0045] Chip 3 is mounted on the upper surface of heat conductor 2. Therefore, the upper dimension of heat conductor 2 is the same as or slightly larger than the dimension of the chipset to be installed. Simultaneously, its upper dimension is slightly smaller than the dimension of the upper heat conductor cavity 10 of the dielectric, and its lower dimension is slightly smaller than the dimension of the lower heat conductor cavity 11 of the dielectric. The sum of the thickness of the upper part of heat conductor 2 and the thickness of chip 3 is basically consistent with the depth of the upper heat conductor cavity 10 and the chip cavity 9. Based on this dimensional matching relationship, after chip 3 is installed, its surface is basically coplanar with the step of chip cavity 9. This step is a signal line bonding layer, which can shorten the length of the bonding wire 12, facilitating signal matching and transmission. The dimension of chip cavity 9 is slightly larger than the dimension of chip 3.

[0046] Preferably, the cover plate 4 is a thin sheet structure, slightly larger than the air cavity 8, with a thickness of 0.1mm to 1mm. Its material can be plastic, glass, ceramic, metal, etc., and it is connected to the base 1 by bonding or welding.

[0047] The present invention also provides a ceramic encapsulation shell assembly, including the above-mentioned ceramic encapsulation shell structure and chip 3. The chip 3 is disposed in chip cavity 9, and the distance between the step of chip cavity 9 and the top surface of chip 3 is less than 0.3 mm. The assembly also includes a PCB board disposed in PCB cavity 21, and the distance between the top surface of PCB board and the bottom of second connection cavity 20 is less than 0.3 mm. The closer the distance, the better, so as to reduce the bonding length and the discontinuity of high-frequency signal transmission, which is beneficial to the matching transmission of high-frequency signals.

[0048] The terms “above,” “below,” and “within” as used above include the number itself; the terms “exceeding” and “excluding” do not include the number itself.

[0049] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific descriptions herein should not be construed as limiting the substance and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention. The various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0050] If the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

Claims

1. A ceramic encapsulation tube structure, characterized in that, The device includes a base and a filter disposed within the base. An internal cavity is provided in the middle of the base, and the internal cavity includes a chip cavity. The base includes a first end, and a first connection cavity is provided on the first end. The filter is located between the internal cavity and the first connection cavity. One end of the filter is disposed on the first connection cavity, and the other end is disposed on the step of the chip cavity, so that the chip packaged in the casing can be connected to an external circuit.

2. The ceramic encapsulation tube structure as described in claim 1, characterized in that, It also includes a first ground conductive layer and a second ground conductive layer. The filter includes multiple resonators and a second conductive post disposed between the multiple resonators. The two ends of the second conductive post are respectively connected to the first ground conductive layer and the second ground conductive layer. The resonator includes a first conductive post and a first conductive strip. The two ends of the first conductive post are respectively connected to the first ground conductive layer and the first conductive strip.

3. The ceramic encapsulation tube structure as described in claim 2, characterized in that, It also includes a second conductive strip, and the number of resonators is set to three. The three resonators are arranged in a triangle, and the three first conductive pillars are connected through the second conductive strip.

4. The ceramic encapsulation tube structure as described in claim 1, characterized in that, It also includes a high-frequency adapter structure. The base also includes a second end corresponding to the first end. A second connection cavity is provided on the second end. The high-frequency adapter structure includes a vertically arranged third conductive post and a horizontally arranged third conductive strip. The third conductive post and the third conductive strip are connected. One end of the high-frequency adapter structure is provided on the step of the second connection cavity, and the other end is provided on the step of the chip cavity for connecting the chip.

5. The ceramic encapsulation tube structure as described in claim 4, characterized in that, A PCB cavity is provided below the second connecting cavity, and the area of ​​the second connecting cavity is larger than the area of ​​the PCB cavity.

6. The ceramic encapsulation tube structure as described in claim 1, characterized in that, It also includes a low-frequency transmission structure. The base also includes a corresponding third end and a fourth end. A third connection cavity is provided on both the third end and the fourth end. The low-frequency transmission structure includes a vertically arranged fourth conductive post and a horizontally arranged fourth conductive strip. The fourth conductive post and the fourth conductive strip are connected. One end of the low-frequency transmission structure is set on the step of the third connection cavity for connecting to an external circuit, and the other end is set on the step of the chip cavity for connecting to a chip.

7. The ceramic encapsulation tube structure as described in claim 4, characterized in that, It also includes several grounding conductive layers and several grounding conductive posts connected together, with the grounding conductive layers and grounding conductive posts located outside the high-frequency switching structure.

8. The ceramic encapsulation tube structure according to any one of claims 1 to 7, characterized in that, It also includes a cover plate and a heat conductor. The internal cavity also includes an air cavity disposed above the chip cavity, and an upper heat conductor cavity and a lower heat conductor cavity disposed below the chip cavity. The internal cavity is through the direction of the line connecting the air cavity and the lower heat conductor cavity. The area of ​​the air cavity is larger than the area of ​​the chip cavity, the area of ​​the chip cavity is not less than the area of ​​the upper heat conductor cavity, and the area of ​​the upper heat conductor cavity is larger than the area of ​​the lower heat conductor cavity. The cover plate is disposed above the air cavity, and the heat conductor is disposed inside the upper heat conductor cavity and the lower heat conductor cavity.

9. A ceramic encapsulation housing assembly, characterized in that, The ceramic encapsulation shell structure and chip included in any one of claims 1 to 8 above, wherein the chip is disposed in a chip cavity and the distance between the step of the chip cavity and the top surface of the chip is less than 0.3 mm.

10. The ceramic encapsulation housing assembly as described in claim 9, characterized in that, It also includes a PCB board disposed in the PCB cavity, wherein the distance between the top surface of the PCB board and the bottom of the second connecting cavity is less than 0.3 mm.

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