Air tightness detection clamp for cavity-free metal welding ceramic packaging shell

Abstract

The invention provides an air tightness detection clamp for a cavity-free metal welding ceramic packaging shell, and belongs to the technical field of ceramic packaging, the air tightness detection clamp comprises a detection shell and a breather pipe, the detection shell is provided with a cavity for accommodating a ceramic substrate, and after the ceramic substrate extends into the cavity, the breather pipe is communicated with the detection shell; the cavity is sealed through a metal ring supported at the opening of the cavity to form a detection sealing cavity; the breather pipe is fixed on the detection shell, communicated with the detection sealing cavity and used for being connected with a vacuum connector of the helium mass spectrum leak detector. According to the air tightness detection clamp for the cavity-free metal welding ceramic packaging shell, the metal ring welded on the ceramic substrate in an embedded mode is a part of a detected piece and also serves as a part of the detection clamp; the detection clamp is simple in structure and convenient to detect and operate, the detected piece is used for sealing, the detection sealing cavity is formed, and the problem of air tightness detection of the cavity-free metal welding ceramic packaging shell is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of ceramic packaging, and particularly relates to an airtightness detection fixture for a cavity-free metal-welded ceramic packaging shell. Background Art

[0002] Conventional ceramic packaging shells include ceramic parts, sealing rings, and leads. Some ceramic parts themselves have internal cavities, or cavities are formed by welding the sealing ring and the ceramic part up and down, or the ceramic part has a through cavity. For such ceramic packaging shells with internal cavities, cavities, or through cavities, a helium mass spectrometer leak detector is usually used for airtightness leak detection. During detection, the unsealed ceramic packaging shell is inverted on the leak hole of the leak detection tray, and it is ensured that there is a tight combination between the ceramic packaging shell and the soft silicone rubber on the leak detection tray to form a sealed cavity. The device is used to evacuate the sealed cavity, and then helium gas is injected into the sealed cavity through the leak hole to detect the airtightness of the welding between the sealing ring and the ceramic part, and the leak detector is used to determine whether the seal at the welding point is qualified.

[0003] The structural characteristics of the cavity-free ceramic packaging shell are as follows: (1) The ceramic part is a planar substrate without an internal cavity itself. The chip is exposed, and the chip is directly mounted on the surface of the substrate and protected by underfill or molding encapsulation, rather than a traditional hermetic packaging cavity.

[0004] (2) The ceramic part and the metal ring are embedded and welded, not welded in an up-and-down structure, and no cavity is formed.

[0005] The cavity-free ceramic packaging adapts to the requirements of high frequency, high power, and low cost through planarization and integration design. Its core advantages are as follows: simplifying the structure, improving heat dissipation and electrical performance; avoiding cavity processing, reducing production costs; and being compatible with advanced packaging technologies (such as flip-chip welding and wafer-level packaging).

[0006] Although the chip is not encapsulated in the cavity, through material innovation (such as high thermal conductivity ceramics) and process optimization (such as underfill), high reliability and performance requirements can still be achieved.

[0007] For such cavity-free ceramic packaging shells, due to the absence of a cavity, it is impossible to use a helium mass spectrometer leak detector to detect the airtightness of the welding part. However, for ceramic packaging shells with a welding relationship between the ceramic substrate and metal parts, airtightness is an important index of the ceramic packaging shell. Therefore, how to achieve the airtightness detection of such cavity-free ceramic packaging shells has become an urgent problem to be solved. Summary of the Invention

[0008] An embodiment of the present invention provides an airtightness detection fixture for a cavity-free metal-welded ceramic packaging shell, aiming to achieve the airtightness detection of cavity-free ceramic packaging shells.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a cavity-less metal-welded ceramic packaging shell airtightness testing fixture, comprising: A detection housing has a cavity for accommodating a ceramic substrate. When the ceramic substrate is inserted into the cavity, the cavity is sealed by a metal ring supported at its opening, forming a sealed detection cavity. A vent tube is fixed to the detection housing and communicates with the detection sealing cavity.

[0010] In one feasible manner, after the ceramic substrate is inserted into the cavity, there is a non-contact gap between the periphery of the ceramic substrate and the inner wall of the cavity.

[0011] In one possible implementation, the opening of the cavity is provided with a clamping assembly for holding the metal ring on the detection housing.

[0012] In one possible implementation, the clamping assembly includes a jaw and a torsion spring, the jaw being connected to the outside of the detection housing via a pivot, and the torsion spring being mounted between the jaw and the detection housing to keep the jaw in a clamping state.

[0013] In one possible implementation, the gripper has a plane that presses against the metal ring.

[0014] In one possible implementation, a sealing strip is provided at the opening of the cavity, and the clamping assembly presses the metal ring and the sealing strip together to seal the detection sealing cavity.

[0015] In one possible implementation, a leak detection hole is provided at the bottom of the detection housing opposite to the opening of the cavity, and the vent pipe is connected to the leak detection hole.

[0016] In one possible implementation, the vent tube is threadedly connected to the leak detection hole, or the vent tube is welded to the bottom of the detection housing.

[0017] In one possible implementation, the opening of the cavity is provided with an annular recessed groove, the bottom surface of which forms an annular step, and the metal ring overlaps the annular step.

[0018] In one possible implementation, the side of the annular sinkhole is adapted to the outer edge of the metal ring to position the ceramic substrate.

[0019] The airtightness testing fixture for a cavity-less metal-welded ceramic package provided by this invention has the following advantages compared to existing technologies: The testing housing has a cavity for accommodating a ceramic substrate. An embedded metal ring welded to the ceramic substrate serves as both part of the test piece and part of the testing fixture. During airtightness testing, the ceramic substrate extends into the cavity, and the metal ring is precisely supported at the cavity opening, acting as both a seal for the cavity and a support for the overall ceramic package. At this time, the weld between the ceramic substrate and the metal ring is located within the testing sealing cavity. Then, by connecting the vacuum connector of a helium gas spectrometer leak detector to a vent pipe, the testing sealing cavity is first evacuated, and then helium is introduced for airtightness testing. This allows for the detection of leaks at the weld between the metal ring and the ceramic substrate, thus achieving airtightness testing for the cavity-less metal-welded ceramic package.

[0020] This testing fixture has a simple structure and is easy to operate. It utilizes the sealed component under test to form a sealed testing cavity, which solves the problem of airtightness testing of cavityless metal-welded ceramic packaging shells. It can meet various packaging requirements of users and is widely used in military equipment systems such as aviation, aerospace, and satellite exploration. Attached Figure Description

[0021] Figure 1 A three-dimensional structural schematic diagram of the airtightness testing fixture for a cavity-less metal-welded ceramic packaging shell provided in an embodiment of the present invention; Figure 2 This is a front view structural schematic diagram of the airtightness testing fixture for a cavityless metal-welded ceramic packaging shell provided in an embodiment of the present invention. Figure 3 For along Figure 2 Cross-sectional view of line AA in the middle; Figure 4 for Figure 3 A schematic diagram of a structure in which a ceramic substrate is inserted and a metal ring is supported at the opening of the cavity; Figure 5 for Figure 2 A top view of the provided airtightness testing fixture for a cavity-less metal-welded ceramic packaging shell; Figure 6 for Figure 2 A side view of the provided airtightness testing fixture for a cavity-less metal-welded ceramic packaging shell; Figure 7 For along Figure 6 Cross-sectional view of the middle BB line; Figure 8 for Figure 7 A schematic diagram of a structure in which a ceramic substrate is inserted and a metal ring is supported at the opening of the cavity; Figure 9This is a schematic diagram of a structure provided in an embodiment of the present invention, showing an annular recessed groove and a matching metal ring at the opening of the detection housing; Figure 10 A schematic diagram of a clamping assembly for clamping a metal ring provided in an embodiment of the present invention (showing a clamping assembly). Explanation of reference numerals in the attached figures: 1. Detection housing; 11. Cavity; 12. Leak detection hole; 2. Vent pipe; 3. Ceramic substrate; 4. Metal ring; 5. Clamping assembly; 51. Rotating shaft; 52. Grippers; 6. Non-contact gap. Detailed Implementation

[0022] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Please see Figures 1 to 10 As shown, the airtightness testing fixture for a cavity-less metal-welded ceramic package shell provided by the present invention will now be described. The airtightness testing fixture for the cavity-less metal-welded ceramic package shell includes a testing housing 1 and a vent pipe 2. The testing housing 1 has a cavity 11 for accommodating a ceramic substrate 3. When the ceramic substrate 3 extends into the cavity 11, the cavity 11 is sealed by a metal ring 4 supported at its opening, forming a testing sealed cavity. The vent pipe 2 is fixed to the testing housing 1 and communicates with the testing sealed cavity, serving as a connection to the vacuum connector of a helium gas spectrometer leak detector.

[0024] The airtightness testing fixture for a cavity-less metal-welded ceramic package provided by this invention has the following advantages compared with the prior art: The testing housing 1 is provided with a cavity 11 to accommodate a ceramic substrate 3. The metal ring 4 embedded and welded on the ceramic substrate 3 is both part of the test piece and part of the testing fixture. During airtightness testing, the ceramic substrate 3 extends into the cavity 11, and the metal ring 4 is precisely supported at the opening of the cavity 11. At this time, it acts as a seal for the cavity 11 and also as a support for the overall ceramic package. Meanwhile, the weld between the ceramic substrate 3 and the metal ring 4 is located within the testing sealing cavity. Then, the vacuum connector of the helium gas spectrometer leak detector is connected to the vent pipe 2. The testing sealing cavity is first evacuated, and then helium is introduced for airtightness testing. This allows for the detection of whether there is leakage at the weld between the metal ring 4 and the ceramic substrate 3, thus realizing the airtightness testing of the cavity-less metal-welded ceramic package.

[0025] This testing fixture has a simple structure and is easy to operate. It utilizes the sealed part under test to form a sealed testing cavity, which solves the problem of airtightness testing of cavityless metal-welded ceramic packaging shells. This fixture can be extended to other similar shells without internal cavities but with welded metal parts and airtightness testing requirements. It can meet various packaging requirements of users and is widely used in aviation, aerospace, satellite exploration and other systems.

[0026] In some embodiments, see Figure 4 , Figures 8 to 10 As shown, after the ceramic substrate 3 is inserted into the cavity 11, there is a non-contact gap 6 between the ceramic substrate 3 and the inner wall of the cavity 11.

[0027] This non-contact gap 6 has many beneficial effects. On the one hand, it provides space for helium gas during leak detection, allowing the helium gas to directly and completely contact the annular weld between the metal ring 4 and the ceramic substrate 3, thereby improving the reliability of the airtightness test. On the other hand, it can effectively avoid wear caused by direct friction between the ceramic substrate 3 and the inner wall during insertion into the cavity 11, extending the service life of the ceramic substrate 3 and ensuring the stability of its performance.

[0028] In some embodiments, see Figure 10 As shown, a clamping assembly 5 is provided at the opening of the cavity 11 to hold the metal ring 4 on the detection housing 1. By clamping the metal ring 4 with the clamping assembly 5, the ceramic substrate 3 extending into the cavity 11 can be positioned, avoiding direct contact between one side of the ceramic substrate 3 and the inner wall of the cavity 11, which would prevent helium gas from reaching this part of the weld and causing a missed detection. On the other hand, by clamping the metal ring 4, the metal ring 4 can also be in close contact with the opening of the cavity 11, thereby ensuring the reliability of the detection of the sealed cavity density. Therefore, by clamping the metal ring 4 with the clamping assembly 5, the reliability of the airtightness detection can be improved.

[0029] This application provides clamping components 5 around the detection housing 1 or around the metal ring 4, for example, one clamping component 5 on each side, for a total of four clamping components 5, to clamp the metal ring 4 from four directions, ensuring that the metal ring 4 fits tightly against the detection housing 1.

[0030] In some embodiments, see Figure 10As shown, the clamping assembly 5 includes a jaw 52 and a torsion spring (not shown in the figure, but can be installed in a conventional manner). The jaw 52 is connected to the outside of the detection housing 1 via a rotating shaft 51. The torsion spring is installed between the jaw 52 and the detection housing 1 to keep the jaw 52 in a clamping state. This clamping assembly 5 has a simple structure, is easy to install and operate, and provides reliable clamping. The torsion spring ensures that the jaw 52 can be stably held in the clamping state, ensuring that the object being detected will not easily shake or fall off during the detection process, thereby guaranteeing the accuracy and stability of the detection. The rotating shaft 51 connects the jaw 52 to the detection housing 1, allowing the jaw 52 to rotate flexibly, facilitating clamping operations on objects under different conditions, and improving the versatility and applicability of the clamping assembly 5. In addition, this simple and effective structural design reduces production costs, facilitates installation and maintenance, improves the efficiency and reliability of the detection work, and provides a strong guarantee for the smooth progress of the detection work.

[0031] Preferably, a support for mounting the rotating shaft 51 is provided on the outside of the detection housing 1 to provide a mounting structure for the rotating shaft 51.

[0032] In some embodiments, see Figure 10 As shown, the gripper 52 has a flat surface for pressing the metal ring 4. By tightly fitting the metal ring 4 with this flat surface, the metal ring 4 can be reliably fixed and clamped, effectively preventing the metal ring 4 from loosening or shifting during subsequent operations, thereby ensuring the stability and reliability of the detection process, and also ensuring the reliability of the seal between the metal ring 4 and the cavity 11.

[0033] Optionally, a flexible pad or rubber pad (not shown in the figure) is provided on the plane of the gripper 52 to avoid damage to the metal ring 4. At the same time, when the gripper 52 clamps, the flexible pad or rubber pad cushions the metal ring 4 to avoid impact force and damage.

[0034] In some embodiments, a sealing strip (not shown) is provided at the opening of the cavity 11, and the clamping assembly 5 presses the metal ring 4 and the sealing strip together to seal the detection sealing cavity.

[0035] The tight fit between the sealing strip and the metal ring 4 effectively prevents external dust, moisture and other impurities from entering the detection sealing cavity, ensuring the purity of the cavity environment and thus improving the accuracy and reliability of the detection. Good sealing performance can prevent gas leakage in the cavity, maintain stable pressure and gas composition in the cavity, and provide stable conditions for the detection work.

[0036] The sealing strip is a closed ring, which can be pasted onto the opening of cavity 11.

[0037] In some embodiments, see Figures 3 to 5A leak detection hole 12 is provided at the bottom of the detection housing 1, which is opposite to the opening of the cavity 11. The vent pipe 2 is connected to the leak detection hole 12. During the airtightness test, the vacuum connector of the helium gas spectrometer leak detector is installed on the vent pipe 2, and helium gas enters the test sealing cavity through the vent pipe 2 and the leak detection hole 12.

[0038] In some embodiments, see Figures 2 to 4 As shown, the vent pipe 2 is connected to the leak detection hole 12 by a thread, or the vent pipe 2 is welded to the bottom of the detection housing 1 (the figure shows the vent pipe 2 welded to the detection housing 1). The size of the vent pipe 2 can be adapted to the vacuum connector of the helium gas spectrometer leak detector, improving the versatility of the entire detection fixture.

[0039] In some embodiments, see Figure 9 As shown, an annular recessed groove is provided at the opening of the cavity 11, and the bottom surface of the annular recessed groove forms an annular step, with the metal ring 4 overlapping on the annular step.

[0040] On the one hand, the design of the annular sinkhole and the annular step can accurately position the metal ring 4, making its overlap more stable and effectively preventing the metal ring 4 from shaking or shifting during use, thus ensuring the stability and reliability of the entire structure. On the other hand, this structure is conducive to improving sealing performance. The tight overlap between the metal ring 4 and the annular step can better prevent external substances from entering the cavity 11, preventing leakage of substances inside the cavity 11, providing reliable protection for the environment inside the cavity 11, and ensuring the normal operation of related functions.

[0041] In some embodiments, see Figure 9 As shown, the side of the annular recessed groove is adapted to the outer edge of the metal ring 4 to position the ceramic substrate 3. In the above technical solution, the ceramic substrate 3 is positioned by adapting the side of the annular recessed groove to the metal ring 4, so that the ceramic substrate 3 does not stick tightly to the inner wall of the cavity 11, and the ceramic substrate 3 can be positioned more accurately during the installation process, effectively avoiding the problem of missed detection due to installation position deviation.

[0042] During the airtightness test, the ceramic substrate 3 is inserted into the cavity 11 of the test housing 1, the metal ring 4 is supported on the opening of the cavity 11, and the metal ring 4 is clamped by the clamping assembly 5.

[0043] Connect the vacuum connector of the helium gas spectrometer leak detector to the vent pipe 2, first evacuate the vacuum, then inject helium gas, detect the leak rate, and display the detection data on the display screen.

[0044] A leak rate judgment value is preset on the helium gas spectrometer. If the detected data exceeds the preset leak rate judgment value, the weld airtightness is unqualified; otherwise, it is qualified.

[0045] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A gas tightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell, characterized in that, include: The detection housing (1) has a cavity (11) for accommodating a ceramic substrate (3). When the ceramic substrate (3) is inserted into the cavity (11), the cavity (11) is sealed by a metal ring (4) supported at its opening to form a detection sealing cavity; and A vent pipe (2) is fixed to the detection housing (1) and communicates with the detection sealing cavity.

2. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 1, characterized in that, After the ceramic substrate (3) is inserted into the cavity (11), there is a non-contact gap (6) between the ceramic substrate (3) and the inner wall of the cavity (11).

3. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 1, characterized in that, The opening of the cavity (11) is provided with a clamping assembly (5) for clamping the metal ring (4) on the detection housing (1).

4. The airtightness testing fixture for the cavity-less metal-welded ceramic encapsulation shell as described in claim 3, characterized in that, The clamping assembly (5) includes a jaw (52) and a torsion spring. The jaw (52) is connected to the outside of the detection housing (1) via a pivot (51). The torsion spring is installed between the jaw (52) and the detection housing (1) so that the jaw (52) is in a clamping state.

5. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 4, characterized in that, The gripper (52) has a plane that presses against the metal ring (4).

6. The airtightness testing fixture for the cavity-less metal-welded ceramic encapsulation shell as described in claim 3, characterized in that, A sealing strip is provided at the opening of the cavity (11), and the clamping assembly (5) presses the metal ring (4) and the sealing strip together to seal the detection sealing cavity.

7. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 1, characterized in that, The bottom of the detection housing (1) opposite to the opening of the cavity (11) is provided with a leak detection hole (12), and the vent pipe (2) is connected to the leak detection hole (12).

8. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 7, characterized in that, The vent pipe (2) is connected to the leak detection hole (12) by a thread, or the vent pipe (2) is welded to the bottom of the detection housing (1).

9. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 1, characterized in that, An annular sinking groove is provided at the opening of the cavity (11), and the bottom surface of the annular sinking groove forms an annular step. The metal ring (4) overlaps on the annular step.

10. The airtightness testing fixture for a cavity-less metal-welded ceramic encapsulation shell as described in claim 9, characterized in that, The side of the annular sink groove is adapted to the outer edge of the metal ring (4) to position the ceramic substrate (3).

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