Ceramic tube shell
The ceramic tube shell design with a plate-like base and boss structure addresses the processing and warping issues of traditional ceramic rings by ensuring a preset wire bonding height and thicker ceramic ring, enhancing processing ease and stability.
Patent Information
- Application Number
- CN202420831686.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-19
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-04-19
AI Technical Summary
Traditional ceramic tube shells require thin ceramic rings that are difficult to process and prone to warping and deformation during assembly due to inconsistent thermal expansion coefficients, especially in high-power semiconductor packaging devices.
A ceramic tube shell design featuring a plate-like base with a boss for mounting the chip and a ceramic ring fixed on the base, where the boss is exposed, and a fin is attached to the ring, ensuring a preset wire bonding height while allowing a thicker ceramic ring, reducing processing difficulty and warping.
The design achieves a preset wire bonding height while allowing a thicker ceramic ring, reducing processing difficulty and minimizing warping during welding, thus meeting the requirements of high-power semiconductor packaging.
Smart Images
Figure CN222168384U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of ceramic tube shells, and in particular, to a ceramic tube shell. Background Art
[0002] With the development of the electronics industry, the requirements for high-density integration of electronic components have increased accordingly. High integration, high power and high reliability are the current development trends of semiconductor packaging devices, which puts higher requirements on the packaging shell. The shell needs better heat dissipation performance to meet the reliability requirements. Traditional plastic shells can no longer meet the heat dissipation and electrical performance requirements of future high-power devices. Ceramic shells have become a better choice.
[0003] Since the package design limits the size of the device, especially the height difference from the upper surface of the chip fixed in the ceramic tube shell to the upper surface of the fin (i.e. the wire bonding height) cannot be changed. Under this premise, changing from a plastic tube shell solution to a ceramic tube shell solution will result in a particularly thin ceramic ring, which is usually between 0.3 and 0.6 mm thick. Usually, the ceramic ring tube shell is welded.
[0004] Figure 1 FIG. 1 is a schematic diagram of the structure of an existing ceramic tube shell. Figure 1 As shown, 1 is a heat sink, 2 is a ceramic ring, and 3 is a fin. Since the thermal expansion coefficients of the ceramic ring 2 (made of alumina) and the fin 3 (made of Kovar alloy) are inconsistent, the ceramic ring will warp after high-temperature welding.
[0005] Under the rigid requirement that the bonding height cannot be changed, the thickness of the ceramic ring is only 0.5mm. Such a thin ceramic ring is very difficult to process on the one hand, and on the other hand, during the welding process, especially when the heat sink is a flat plate structure with a large length and width ratio, the thermal expansion coefficients of the heat sink, ceramic ring, and fin are different, causing the ceramic ring to warp. In particular, thin, long, and narrow ceramic rings are more likely to suffer from severe warping.
[0006] Figure 2 This is the outline of an existing ceramic ring. Using the ceramic ring as the reference plane, the outline is scanned out, and the height difference is represented by the depth of color, such as red is high and purple is low. The specific value can refer to the number on the right side of the color vertical axis. The horizontal axis represents the horizontal distance, and the numerical axis represents the vertical height difference, in microns.
[0007] Figure 3 for Figure 2 The warpage curve of the ceramic ring shown in the figure shows that the horizontal axis represents the horizontal distance and the numerical axis represents the vertical height difference in microns. The red dotted line with an arrow represents the height fluctuation along the length of the ceramic ring. Figure 2 The ceramic ring shown has a thickness of 0.55 mm and an aspect ratio of about 2.1. Figure 3 As shown, the warpage is 90 microns.
[0008] Figure 4 This is the outline of another existing ceramic ring. Using the ceramic ring as the reference plane, the outline is scanned out, and the height difference is represented by the depth of color, such as red is high and purple is low. The specific value can refer to the number on the right side of the color vertical axis. The horizontal axis represents the horizontal distance, and the number axis represents the vertical height difference, in microns.
[0009] Figure 5 for Figure 4 The warpage curve of the ceramic ring shown in the figure shows that the horizontal axis represents the horizontal distance and the numerical axis represents the vertical height difference in microns. The red dotted line with an arrow represents the height fluctuation along the length of the ceramic ring. Figure 4 The ceramic ring shown has a thickness of 0.5 mm and an aspect ratio of about 3.3. Figure 5 As shown, the warpage is 280 microns. Ceramic rings with large aspect ratios are more susceptible to deformation.
[0010] Therefore, the traditional ceramic tube shell requires the ceramic ring to be of smaller thickness, is more difficult to process and is prone to warping and deformation during the assembly process, which is a technical problem that technical personnel in this field urgently need to solve.
[0011] The above information disclosed in the background section is only for enhancing understanding of the background of the present application and therefore it may contain information that does not form the prior art known to a person of ordinary skill in the art. Utility Model Content
[0012] The embodiment of the present application provides a ceramic tube shell to solve the technical problems that the traditional ceramic tube shell requires the ceramic ring to be of smaller thickness, is more difficult to process and is prone to warping and deformation during the assembly process.
[0013] The present application provides a ceramic tube shell, comprising:
[0014] A heat sink, the heat sink comprising a plate-shaped base and a boss fixed to a side surface of the plate-shaped base for mounting a chip;
[0015] A ceramic ring is fixed on the plate-shaped base, and the boss is exposed from a hollow position of the ceramic ring;
[0016] A fin fixed on the surface of the ceramic ring;
[0017] The thicknesses of the boss, the ceramic ring and the chip are matched to ensure that the height difference H between the upper surface of the chip mounted on the boss and the upper surface of the fin is a preset wire bonding height.
[0018] The embodiment of the present application adopts the above technical solution, which has the following technical effects:
[0019] The design of power devices requires that the height difference H between the upper surface of the chip and the upper surface of the fin reach a preset wire bonding height. The ceramic tube shell of the embodiment of the present application not only meets the requirement of this preset wire bonding height, but also realizes that the thickness of the ceramic ring is relatively large. On the one hand, the processing difficulty of the ceramic ring is reduced. On the other hand, the thicker ceramic ring is less likely to warp during welding.
[0020] In the ceramic tube shell of the embodiment of the present application, the heat sink is not a traditional flat plate structure, but includes a plate-like base and a boss for mounting the chip fixed on a side surface of the plate-like base. The ceramic ring is fixed on the plate-like base, and the boss is exposed from the hollow position of the ceramic ring. The fin is fixed on the surface of the ceramic ring. When the height difference H from the upper surface of the chip to the upper surface of the fin is a preset wire bonding height, the upper surface height of the chip fixed on the boss is relatively high, which provides space for the thickness of the ceramic ring, so that the thickness of the ceramic ring can be relatively large. Therefore, the ceramic tube shell of the embodiment of the present application, through the heat sink having a boss of a certain thickness and a ceramic ring with a larger thickness, and the chip, meets the rigid requirement that the height difference H from the upper surface of the chip to the upper surface of the fin is a preset wire bonding height. The thickness of the ceramic ring in the ceramic tube shell of the embodiment of the present application is relatively large. On the one hand, the processing difficulty is relatively low. On the other hand, the ceramic ring with a larger thickness has less warping deformation during welding with the fin. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0022] Figure 1 It is a structural schematic diagram of an existing ceramic tube shell;
[0023] Figure 2 This is an outline diagram of an existing ceramic ring;
[0024] Figure 3 for Figure 2 Warpage curve diagram of the ceramic ring shown;
[0025] Figure 4 This is an outline drawing of another existing ceramic ring;
[0026] Figure 5 for Figure 4 Warpage curve diagram of the ceramic ring shown;
[0027] Figure 6 A side view of a ceramic tube shell according to an embodiment of the present application;
[0028] Figure 7 for Figure 6 A perspective view of the ceramic tube shell shown;
[0029] Figure 8 for Figure 6 A partial stereoscopic view of the ceramic tube shell from another angle;
[0030] Fig. 9 for Figure 6 A schematic diagram of a heat sink for a ceramic tube shell is shown;
[0031] Fig.10 for Figure 6 The AA cross-sectional view is shown and a schematic diagram of chip installation and wire bonding is shown;
[0032] Fig.11 for Figure 6 An outline view of the ceramic ring of the ceramic tube shell shown;
[0033] Fig.12 for Fig.11 Warpage curve graph of the ceramic ring shown.
[0034] Reference numerals:
[0035] In the background technology:
[0036] Heat sink 1, ceramic ring 2, fin 3.
[0037] In this application:
[0038] Heat sink 100, plate base 110, boss 120,
[0039] Ceramic ring 200,
[0040] Fin 300,
[0041] Chip 400. DETAILED DESCRIPTION
[0042] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.
[0043] Embodiment 1
[0044] like Figure 6 , Figure 7 , Figure 8 , Fig. 9 , Fig.10 As shown, the ceramic tube shell of the embodiment of the present application includes:
[0045] A heat sink 100, comprising a plate-shaped base 110 and a boss 120 fixed to a side surface of the plate-shaped base for mounting a chip;
[0046] The ceramic ring 200 is fixed on the plate-shaped base 110, and the boss 120 is exposed from the hollow position of the ceramic ring 200;
[0047] The fin 300 is fixed on the surface of the ceramic ring 200;
[0048] The thicknesses of the boss 120 , the ceramic ring 200 , and the chip 400 are matched to ensure that the height difference H between the upper surface of the chip 400 mounted on the boss and the upper surface of the fin 300 is a preset bonding height.
[0049] The design of power devices requires that the height difference H between the upper surface of the chip and the upper surface of the fin reach a preset wire bonding height. The ceramic tube shell of the embodiment of the present application not only meets the requirement of this preset wire bonding height, but also realizes that the thickness of the ceramic ring is relatively large. On the one hand, the processing difficulty of the ceramic ring is reduced. On the other hand, the thicker ceramic ring is less likely to warp during welding.
[0050] In the ceramic shell of the embodiment of the present application, the heat sink is not a traditional flat plate structure, but includes a plate-like base and a boss for mounting the chip fixed on a side surface of the plate-like base. The ceramic ring is fixed on the plate-like base, and the boss is exposed from the hollow position of the ceramic ring. The fin is fixed on the surface of the ceramic ring. When the height difference H from the upper surface of the chip to the upper surface of the fin is a preset wire bonding height, the upper surface height of the chip fixed on the boss is relatively high, which provides space for the thickness of the ceramic ring, so that the thickness of the ceramic ring can be relatively large. Therefore, the ceramic shell of the embodiment of the present application, through the heat sink having a boss of the first thickness and a ceramic ring with a larger thickness, and the chip, meets the rigid requirement that the height difference H from the upper surface of the chip to the upper surface of the fin is a preset wire bonding height. The thickness of the ceramic ring in the ceramic shell of the embodiment of the present application is relatively large. On the one hand, the processing difficulty is relatively low. On the other hand, the ceramic ring with a larger thickness has less warping deformation during welding with the fin.
[0051] In implementation, such as Figure 7 , Figure 8 , Fig.10 As shown, the thickness of the ceramic ring 200 is greater than the thickness of the boss 120 , and the upper surface of the boss 120 is lower than the upper surface of the fin 300 .
[0052] In this way, the upper surface of the boss is lower than the upper surface of the ceramic ring. When the chip is fixed on the upper surface of the boss, the chip is still lower than the upper surface of the fin. This has a certain protective effect on the chip and is also convenient for subsequent assembly.
[0053] In implementation, the thickness of the boss ranges from greater than or equal to 0.01 mm to less than or equal to 5 mm.
[0054] The thicknesses of the boss, the ceramic ring and the chip are matched to ensure that the height difference H between the upper surface of the chip mounted on the boss and the upper surface of the fin is a preset wire bonding height.
[0055] In implementation, the thickness of the ceramic ring ranges from greater than or equal to 0.6 mm to less than or equal to 6 mm.
[0056] The thickness of the ceramic ring in the background art is about 0.5 micrometers. The ceramic ring of the ceramic tube shell of the embodiment of the present application is thicker, less difficult to process, and less likely to warp and deform during welding.
[0057] In implementation, the aspect ratio of the ceramic ring is in the range of greater than or equal to 1 and less than or equal to 5.
[0058] The thickness range of the ceramic ring is greater than or equal to 0.6 mm and less than or equal to 6 mm. The ceramic rings with an aspect ratio within this range have relatively small processing difficulty and warping deformation.
[0059] As an practicable manner, the ceramic ring and the plate-shaped base are fixed by gluing.
[0060] The ceramic ring and the plate-shaped base are fixed by gluing, which has lower cost and can meet the flatness requirements.
[0061] As another practicable manner, the ceramic ring and the plate-shaped base are fixed by welding.
[0062] The ceramic ring and the plate-shaped base are fixed by welding, which has better flatness but slightly higher cost.
[0063] You can choose according to actual needs.
[0064] As an practicable manner, the fin is welded and fixed on the surface of the ceramic ring.
[0065] As another feasible manner, the fin is bonded and fixed to the surface of the ceramic ring.
[0066] The fins may be fixed to the ceramic ring by welding or bonding, and the method may be selected according to actual needs.
[0067] In implementation, the heat sink is a heat sink with an integrated structure.
[0068] In implementation, the boss is welded and fixed to a side surface of the plate-shaped base.
[0069] Specifically, the material of the boss can be consistent with that of the plate-like base, such as copper, molybdenum copper or CPC composite material. The processing method can be welding the boss and the plate-like base together, or a whole plate can be processed by stamping, wire cutting or CNC machining, which is not limited here.
[0070] In practice, the flatness of the upper surface of the boss is less than 0.015 mm to meet the core bonding requirements.
[0071] In practice, the surface of the ceramic ring at the position where it is welded to the fin is metallized to achieve welding.
[0072] Fig.11 for Figure 6 The outline of the ceramic ring of the ceramic tube shell shown in the figure. The outline is scanned with the ceramic ring as the reference plane. The height difference is represented by the depth of color, such as red is high and purple is low. The specific value can refer to the number on the right side of the color vertical axis. The horizontal axis represents the horizontal distance, and the numerical axis represents the vertical height difference in microns.
[0073] Fig.12 for Fig.11 The warpage curve of the ceramic ring shown in the figure shows that the horizontal axis represents the horizontal distance and the numerical axis represents the vertical height difference in microns. The red dotted line with an arrow represents the height fluctuation along the length of the ceramic ring.
[0074] Fig.11 The ceramic ring shown has a thickness of 0.5 mm and an aspect ratio of 2.1. Fig.12 As shown, the warpage is 68 microns.
[0075] In the description of the present application and its embodiments, it should be understood that the orientation or positional relationship indicated by the terms "top", "bottom", "height", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0076] In the present application and its embodiments, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.
[0077] In the present application and its embodiments, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0078] The disclosure above provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described above. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and material examples provided by the present application, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.
[0079] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.
[0080] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.
Claims
1. A ceramic tube shell, characterized in that: include: A heat sink, the heat sink comprising a plate-shaped base and a boss fixed to a side surface of the plate-shaped base for mounting a chip; A ceramic ring is fixed on the plate-shaped base, and the boss is exposed from a hollow position of the ceramic ring; A fin fixed on the surface of the ceramic ring; The thicknesses of the boss, the ceramic ring and the chip are matched to ensure that the height difference H between the upper surface of the chip mounted on the boss and the upper surface of the fin is a preset wire bonding height.
2. The ceramic tube shell according to claim 1, characterized in that: The thickness of the ceramic ring is greater than the thickness of the boss, and the upper surface of the boss is lower than the upper surface of the fin.
3. The ceramic tube shell according to claim 2, characterized in that: The thickness of the boss ranges from greater than or equal to 0.01 mm to less than or equal to 5 mm.
4. The ceramic tube shell according to claim 3, characterized in that: The thickness of the ceramic ring ranges from greater than or equal to 0.6 mm to less than or equal to 6 mm.
5. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The value range of the aspect ratio of the ceramic ring is greater than or equal to 1 and less than or equal to 5.
6. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The ceramic ring and the plate-shaped base are bonded and fixed with glue; Alternatively, the ceramic ring and the plate-shaped base are fixed by welding.
7. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The fins are welded and fixed on the surface of the ceramic ring; Alternatively, the fins are bonded and fixed to the surface of the ceramic ring.
8. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The heat sink is an integrated structure heat sink; Alternatively, the boss is fixed to a side surface of the plate-shaped base.
9. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The flatness of the upper surface of the boss is less than 0.015 mm to meet the core bonding requirements.
10. The ceramic tube shell according to any one of claims 1 to 4, characterized in that: The surface of the position where the ceramic ring is welded to the fin is metallized to achieve welding.