Airtight encapsulation circuit leak detection tool and method of use thereof

Abstract

This application discloses a leak detection fixture for hermetic-sealed encapsulated circuits and its usage method. The leak detection fixture includes at least one leak detection tray and one leak detection basket. The leak detection tray has vent holes and fixing holes at its bottom for supporting the circuit and allowing gas flow. The leak detection basket has a multi-layer tray structure and a detachable movable side beam as a limiting structure, capable of accommodating multiple leak detection trays simultaneously. The usage method is as follows: place the circuit into the leak detection tray, then sequentially place it on each layer of the leak detection basket and insert the movable side beam for fixation; place the entire leak detection basket into a pressure vessel for pressurization; after pressurization, remove the entire leak detection basket, and then remove each leak detection tray individually and place them into a helium mass spectrometer leak detector for leak rate detection. This application can fully utilize the vertical space of the pressure vessel, increase the number of circuits that can be pressurized at one time, achieve rapid batch leak detection, reduce the risk of appearance damage caused by repeated single-circuit handling, and significantly improve leak detection efficiency and product yield.

Description

Technical Field

[0001] This application belongs to the field of integrated circuit reliability testing technology, specifically relating to a leak detection tool for hermetic packaged circuits and its usage method. Background Technology

[0002] In the production of aerospace-grade hybrid integrated circuits, leakage rate testing of hermetically sealed packaged circuits typically employs helium mass spectrometry (HMS). This method requires first pressurizing the circuit with high-pressure helium gas, and then placing the circuit into the vacuum chamber of a leak detector to measure the leakage rate.

[0003] However, existing pressure tank operations have two major bottlenecks: First, to avoid damage to sensitive parts such as gold-plated leads and glass insulators caused by mutual squeezing or friction during circuit stacking, operators can only place the circuits in a single, sparse layer, with anti-static film between layers, and the stacking is restricted, resulting in a serious waste of internal space in the pressure tank; Second, after pressure tanking, each circuit must be transferred from the pressure tank to a tray one by one, and then sent to a leak detector one by one. The entire process relies on manual handling of multiple single-circuit pick-and-place operations, which is cumbersome, time-consuming, and has extremely low efficiency in mass production. More importantly, each pick-and-place operation increases the risk of damage to the appearance of the circuit, directly affecting the product qualification rate.

[0004] Currently, there is no comprehensive solution that can simultaneously address the above issues, ensuring efficient use of pressure tank space, enabling batch leak detection operations, and protecting against cosmetic damage. Summary of the Invention

[0005] The purpose of this application is to provide a leak detection fixture for hermetic encapsulated circuits and its usage method. This addresses the problems of low pressure tank volume utilization, low leak detection efficiency, and easy damage to the circuit appearance in the prior art, as mentioned in the background section.

[0006] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, this application provides a leak detection fixture for a hermetically sealed packaged circuit, comprising: At least one leak detection tray is provided for carrying the circuit to be leaked, and the bottom and / or sidewalls of the leak detection tray are provided with a gas flow structure to facilitate the discharge or entry of gas during the leak detection process; And a leak detection basket frame for simultaneously accommodating multiple leak detection trays, the leak detection basket frame having a multi-layer tray structure, each tray being used to place one leak detection tray, and the leak detection basket frame having a detachable or closable limiting structure to prevent the leak detection trays from sliding out during transfer or pressurization.

[0007] In one possible implementation, the bottom of the leak detection tray is provided with a plurality of leak detection tray air holes, and the four corners of the leak detection tray are respectively provided with leak detection tray fixing holes for installing and placing auxiliary components or fixing components.

[0008] In one possible implementation, the leak detection basket includes: a handle for picking up and putting down the entire leak detection basket; multiple trays for supporting each leak detection tray respectively; a fixed side beam fixedly connected to the trays; and a movable side beam, serving as a limiting structure, which is insertably or removably disposed on the fixed side beam to restrict the leak detection tray from sliding off the trays when inserted.

[0009] In one possible implementation, the pallet is provided with vents for the flow of gas during pressure testing and leak detection; the pallet is fixedly connected to the fixed side beam by angle aluminum and fastening screws.

[0010] In one possible implementation, the external dimensions of the leak detection basket are matched with the internal dimensions of the pressure tank, so that a preset gap is maintained between the leak detection basket and the tank wall after the leak detection basket is installed in the pressure tank, and the number of layers in the height direction of the leak detection basket and the number of trays in each layer are determined according to the volume of the pressure tank and the volume of the leak detector cavity.

[0011] Secondly, this application provides a surface treatment method for a leak detection tray used in the aforementioned leak detection fixture, comprising the following steps: The leak detection tray is subjected to water washing, acid washing, alkaline etching, ultrasonic water washing and drying in sequence; The dried leak detection tray is coated or oxidized to form a non-adsorbent gas layer on its surface.

[0012] Thirdly, this application provides a method for leak detection using the above-mentioned leak detection fixture, comprising the following steps: Step 1: Place the circuit to be tested into multiple leak detection trays, then place each leak detection tray into the respective trays of the leak detection basket frame, and fix them in place by the limiting structure; Step 2: Place the leak detection basket rack containing multiple leak detection trays into the pressure tank for pressure treatment; Step 3: After the pressure tank is completed, remove the leak detection basket frame from the pressure tank as a whole, and then remove the leak detection trays one by one from the leak detection basket frame. Place each leak detection tray into the cavity of the helium mass spectrometer leak detector for leak rate detection. Step 4: After the leak test is completed, remove the circuit from the leak test tray.

[0013] In one possible implementation, step two, the pressure tank treatment includes: sealing the pressure tank, evacuating it, filling it with helium and pressurizing it to a specified pressure value, and maintaining it for a specified time.

[0014] In one possible implementation, in step three, after the leak detection tray is placed into the chamber of the helium mass spectrometer leak detector, the leak detector draws air through the vent at the bottom of the leak detection tray to detect the flow rate of helium gas released from inside the circuit.

[0015] In one possible implementation, the number of leak detection trays placed simultaneously in the leak detection basket is determined based on the volume of the pressure tank and the volume of the leak detector cavity, such that the number of circuits for a single pressure tank processing is greater than the number of circuits for a single leak detection processing.

[0016] Compared with the prior art, this application has the following beneficial effects: This application provides a leak detection fixture for hermetic encapsulated circuits. By incorporating a leak detection tray with a gas flow structure and a leak detection basket with multi-layered support plates and limiting structures, it enables the batch and safe transfer of circuits during pressure tank operation and leak detection. Compared to existing technologies, this fixture improves the utilization rate of pressure tank volume. Furthermore, because the circuits are effectively isolated within the tray, direct impacts and friction between circuits are avoided, significantly reducing the risk of cosmetic damage and providing a structural foundation for subsequent leak detection operations.

[0017] In one possible implementation, multiple vents at the bottom further optimize the gas flow path, ensuring that helium around each circuit is effectively extracted during leak detection, improving the accuracy and consistency of leak rate detection. The mounting holes at the four corners provide mounting positions for the auxiliary components, allowing operators to easily handle individual leak detection trays without direct contact with the circuitry, further reducing the risk of damage.

[0018] In one possible implementation, a handle allows the entire leak detection basket to be picked up and put down as a whole, avoiding the tedious operation of removing each circuit individually and significantly improving handling efficiency. The fixed connection between the fixed side beam and the tray ensures the stability and load-bearing capacity of the multi-layer structure. The movable side beam, as a pluggable limiting structure, is simple in structure and easy to operate, allowing for quick locking or releasing of the leak detection tray without tools, ensuring safety during transportation and facilitating individual removal before leak detection.

[0019] In one possible implementation, the vents on the tray ensure free flow of gas between the upper and lower layers during pressurization and leak detection, avoiding dead airflow caused by tray obstruction, and ensuring that all circuits are uniformly pressurized with helium and evacuated by the leak detector. The connection method of angle aluminum and screws is simple in structure, strong in assembly, low in cost, easy to process and maintain, and facilitates the disassembly and replacement of trays of different specifications to adapt to leak detection trays of different sizes.

[0020] In one possible implementation, through size-matching design, the leak detection basket maintains a preset gap with the tank wall after being installed in the pressure tank. This ensures uniform gas flow while preventing collisions between the basket and the tank. The number of layers and trays is optimized based on the pressure tank volume and the leak detector chamber volume to maximize the single-cycle pressure tank capacity. Simultaneously, it ensures that each removed leak detection tray can be smoothly placed into the leak detector, achieving a balance between the pressure tank and leak detection cycles and preventing equipment downtime.

[0021] A surface treatment method for a leak detection tray involves washing, acid pickling, alkaline etching, ultrasonic washing, drying, and coating / oxidation to form a dense, non-adsorbent protective layer on the tray surface. This method meets the stringent requirements of helium mass spectrometry leak detection for the surface gas emission rate of the tooling. The treated tray will not release interfering gases in a vacuum environment, ensuring the authenticity and accuracy of leak rate detection results. Simultaneously, it improves the tray's corrosion resistance and durability, extending the tooling's service life.

[0022] A leak detection method using a leak detection fixture is disclosed. This method incorporates the operational logic of whole-basket pressure testing and tray-by-tray leak detection into the helium mass spectrometry leak detection process, completely changing the inefficient traditional single-basket, multiple-hand handling mode. Through the complete process of steps one to four, batch processing in the pressure testing stage and rapid switching in the leak detection stage are achieved, improving the overall leak detection efficiency. At the same time, because the circuit is always in a stable and isolated state in the tray, and the number of human touches is reduced, the rate of external damage is lowered.

[0023] In one possible implementation, this step defines the pressure vessel process parameters, ensuring that helium can fully penetrate the circuitry through minute leakage channels. It is compatible with traditional pressure vessel operations, requiring no changes to existing process parameters and equipment, thus reducing implementation complexity. Simultaneously, because the leak detection basket is placed as a whole, all circuits are processed under the same pressure environment, ensuring consistent leak detection conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the leak detection tray structure provided in an embodiment of this application; Figure 2 This is a schematic diagram of the leak detection basket structure provided in an embodiment of this application; Figure 3 This is a schematic diagram of a leak detection tray placed in a leak detection basket frame, as provided in an embodiment of this application.

[0025] The attached diagram is labeled as follows: 1. Air vent on the leak detection tray; 2. Fixing hole on the leak detection tray; 3. Side wall of the leak detection tray; 4. Handle; 5. Tray; 6. Fixed side beam; 7. Angle aluminum; 8. Fastening screw; 9. Movable side beam. Detailed Implementation

[0026] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0027] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly defined. The specific embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0029] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0030] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] Example 1: like Figure 1 As shown, this embodiment provides a leak detection tray. The leak detection tray has a rectangular disk-like structure, with multiple leak detection tray vents 1 evenly distributed on its bottom. The shape of the leak detection tray vents 1 can be round, square, or oblong, and their number and arrangement are determined according to actual needs, with the principle of ensuring that gas can be discharged unimpeded during helium mass spectrometry leak detection. In this embodiment, the leak detection tray vents 1 are round holes with a diameter of 3-5 mm, arranged in a matrix, with a hole spacing of 10-15 mm.

[0033] The leak detection tray has a leak detection tray fixing hole 2 at each of the four corners of its bottom. The leak detection tray fixing hole 2 can be a through hole or a threaded hole, used to install auxiliary components for placement or fixing components. When it is necessary to remove the leak detection tray from the leak detection basket frame separately, a special hook can be used to hook the leak detection tray fixing hole 2 or a stud can be screwed into the leak detection tray fixing hole 2 as a handle.

[0034] The height and diameter of the side wall 3 of the leak detection tray are designed according to the volume and structure of the helium mass spectrometer leak detector chamber to ensure that a single leak detection tray can be smoothly placed into the leak detector chamber, and to maintain a gap of 5-10mm between the tray and the inner wall of the chamber, so as to ensure gas flow and convenient handling. In this embodiment, the external dimensions of the leak detection tray are designed as follows: length 200mm, width 150mm, and side wall height 30mm.

[0035] The leak detection tray is made of aluminum alloy due to its good machinability and low gas escaping rate. To meet the requirement of helium mass spectrometry leak detection that the surface does not adsorb gases, the surface of the leak detection tray undergoes special treatment. The specific surface treatment process is as follows (see Example 2 for details): (1) Water washing: Rinse the surface with deionized water to remove residual oil and particles from the process; (2) Pickling: Soak in 5%-10% dilute sulfuric acid or dilute hydrochloric acid solution for 5-10 minutes to remove oxide scale; (3) Alkaline etching: Soak the surface in a 3%-5% sodium hydroxide solution for 3-5 minutes to further clean it; (4) Ultrasonic water washing: Ultrasonic cleaning in deionized water for 10-15 minutes to remove residual chemical reagents; (5) Drying: Dry in an oven at 80-100℃ for more than 30 minutes to ensure that there is no water vapor on the surface; (6) Coating or oxidation treatment: Depending on the actual needs, processes such as anodizing, electroless nickel plating, and gold plating can be used to form a dense, non-adsorbent protective layer on the surface of the leak detection tray. In this embodiment, hard anodizing is preferred, and the oxide film thickness is controlled at 10-20 μm.

[0036] like Figure 2 As shown, this embodiment provides a leak detection basket frame. The leak detection basket frame adopts a frame structure and is composed of a handle 4, a support plate 5, a fixed side beam 6, an angle aluminum 7, fastening screws 8, and a movable side beam 9.

[0037] The handle 4 is U-shaped or inverted U-shaped and is located at the top of the leak detection basket frame for manual grabbing by operators or hooking by hoisting equipment. The two ends of the handle 4 are respectively inserted into the uppermost limiting holes of the opposite fixed side beams 6 and fixed by riveting, threaded connection or welding.

[0038] There are four fixed side beams 6, located at the four corners of the leak detection basket frame, extending vertically. Each fixed side beam 6 has multiple mounting holes spaced along its height for connecting the support plate 5 and the movable side beam 9. The fixed side beams 6 are made of angle steel or square steel tubing, possessing sufficient structural strength.

[0039] The support plate 5 is a rectangular flat plate structure with multiple air holes for gas flow during pressure tank operation and leak detection. The four corners of the support plate 5 are fixedly connected to four fixed side beams 6 via angle brackets 7 and fastening screws 8. Specifically, one side of the angle bracket 7 is flush with the bottom surface of the support plate 5, and the other side is flush with the inner surface of the fixed side beam 6. The fastening screws 8 pass through the through holes in the angle bracket 7 and are screwed into the threaded holes in the fixed side beam 6 to reliably fix the support plate 5. The number of support plates 5 is determined according to the height of the pressure tank and the height of the leak detector chamber; in this embodiment, 4-6 layers are used, with a layer spacing of 50-80mm.

[0040] The movable side beam 9 serves as a limiting structure, and can be inserted into or removed from the fixed side beam 6. Specifically, on the front and rear sides of the leak detection basket, at the corresponding position of each tray 5, slots or insertion holes are respectively opened on the left and right fixed side beams 6. After the leak detection tray is placed on the tray 5, the movable side beam 9 is inserted from one side, passing through the leak detection end or the stop bar, and inserted into the insertion hole of the fixed side beam 6 on the other side, forming a lateral limiting, thereby preventing the leak detection tray from slipping out during handling or pressurization. The movable side beam 9 can be a round rod, a square rod, or a flat steel bar, and one end can be equipped with an anti-detachment handle or an elastic buckle to prevent accidental detachment during transportation.

[0041] like Figure 3As shown, multiple leak detection trays are sequentially placed onto the trays of the leak detection basket rack, forming a stacked structure. After each leak detection tray is placed, the movable side beam 9 of that layer is inserted for restraint, and then the next layer is placed. Once all trays are in place, the entire unit is carried to the pressure tank or leak detector location using the handle 4.

[0042] Example 2: This embodiment provides a surface treatment method for a leak detection tray, used in the leak detection tray described in Embodiment 1, to ensure that it meets the stringent requirement of helium mass spectrometry leak detection for a surface that does not adsorb gases. The method includes the following steps: Step S1: Wash with water Immerse the machined leak detection tray in a deionized water bath and rinse the surface and internal channels with flowing deionized water for at least 5 minutes to remove visible contaminants such as cutting oil and metal shavings.

[0043] Step S2: Pickling Immerse the rinsed leak detection tray in the pickling tank. The pickling solution is a 5%-10% (v / v) dilute sulfuric acid or dilute hydrochloric acid solution, with the temperature controlled at 20-30℃ and the immersion time at 5-10 minutes. Pickling further removes surface oxide scale and minor rust. Rinse twice with deionized water after pickling.

[0044] Step S3: Alkali etching Immerse the pickled leak detection tray in an alkaline etching tank. The alkaline etching solution is a 3%-5% sodium hydroxide solution, with the temperature controlled at 40-60℃ and the immersion time at 3-5 minutes. Alkaline etching removes the residual gray-black film layer after pickling, giving the surface a uniform metallic luster. Rinse twice with deionized water after alkaline etching.

[0045] Step S4: Ultrasonic water washing Place the alkaline-etched leak detection tray into an ultrasonic cleaner, add deionized water, set the ultrasonic frequency to 40-80kHz, and clean for 10-15 minutes. Ultrasonic cleaning can reach hard-to-clean areas such as pores and inner corners, ensuring no chemical residue remains.

[0046] Step S5: Drying Place the ultrasonically cleaned leak detection tray into an oven, set the temperature to 80-100℃, and dry for no less than 30 minutes until the surface is completely dry and free of water stains or watermarks.

[0047] Step S6: Surface coating or oxidation treatment Based on the specific usage environment and cost considerations, select any of the following processes: Anodizing: The dried leak detection tray is used as the anode and anodized in a sulfuric acid electrolyte to form a dense alumina film with a thickness of 10-20 μm. The oxide film is chemically stable, does not adsorb gases, and is wear-resistant and corrosion-resistant.

[0048] Electroless nickel plating: A nickel-phosphorus alloy layer with a thickness of 5-10 μm is deposited on the surface of the leak detection tray through a chemical reduction reaction. The nickel plating layer is dense and uniform, with an extremely low gas leakage rate.

[0049] Gold plating: A pure gold layer, 0.5-2 μm thick, is electroplated onto a nickel substrate. Gold plating offers the strongest chemical inertness and is suitable for ultra-high vacuum environments.

[0050] After processing, gently wipe the surface with non-woven fabric or clean silk cloth. Check for defects such as peeling, flaking, and color difference before putting it into use.

[0051] Example 3: This embodiment provides a complete operation method for performing helium mass spectrometry leak detection on a certain type of DC / DC hybrid integrated circuit using the above-mentioned leak detection fixture.

[0052] Check that the leak detection tray and leak detection basket are clean and undamaged, and that the movable side beam 9 can be inserted and removed smoothly.

[0053] Prepare the circuit to be tested for leaks.

[0054] Confirm that the helium mass spectrometer leak detector, pressure tank, helium source, and other equipment are in normal working order.

[0055] Step 1: Plating Place the circuits to be tested into the leak detection trays. Each tray contains 20 circuits (arranged in a 5×4 matrix), maintaining a distance of at least 5mm between the circuits to ensure they do not touch each other. Then, place each tray sequentially onto the respective shelf of the leak detection rack. In this embodiment, the leak detection rack has 5 shelves, with 1 tray on each shelf, for a total of 5 trays and 100 circuits (the remaining 20 are for the next batch). After each tray is placed, immediately insert the movable side beam 9 of that shelf to ensure it is securely locked.

[0056] Step 2: Pressure Vessel Using handle 4, move the leak detection basket containing 5 leak detection trays to the front of the pressure tank and place it smoothly into the inner cavity of the pressure tank. Close the pressure tank's sealing door and turn on the vacuum system to evacuate the pressure tank to below 10 Pa. Then, open the helium valve and fill the pressure tank with high-purity helium (purity ≥ 99.99%), pressurizing it to 300 kPa (this pressure can also be adjusted within the range of 200-500 kPa according to process requirements). Close the valve and maintain this pressure for 120 minutes to allow the helium to fully penetrate any potential leaks within the circuit under pressure.

[0057] Step 3: Leak Detection After the pressure tank is pressurized, first open the vent valve to release the internal gas. Once the pressure drops to atmospheric pressure, open the sealed door and remove the entire leak detection basket frame using handle 4. Transfer it to the side of the leak detector's workbench. Then, pull out the movable side beams 9 layer by layer and remove the leak detection trays one by one. Place each leak detection tray into the vacuum chamber of the helium mass spectrometer leak detector in sequence and close the chamber door. The leak detector automatically starts the vacuum pumping program, evacuating the chamber through the vent 1 at the bottom of the leak detection tray. If there is a leak in the circuit, the helium gas that has seeped in will be extracted and enter the mass spectrometer chamber. The leak detector measures the partial pressure of the helium gas and calculates the leak rate. Record the leak rate data for each circuit in each tray and mark the defective products.

[0058] Step 4: Discharge After leak detection is complete, open the leak detector chamber and remove the leak detection tray. Remove the qualified circuits from the tray and place them in a dedicated transfer fixture for the next process. Isolate and label any unqualified circuits. The leak detection tray and basket can be reused after cleaning.

[0059] Example 4: Variation 1: Leak detection baskets with different numbers of layers Depending on the height of the pressure tank, the number of layers in the leak detection basket can be set to 2, 3, 4, 5, 6 or more. The more layers, the larger the single pressure tank capacity, but it is necessary to ensure that there is sufficient space (no less than 20mm) between the top layer circuit and the top of the pressure tank.

[0060] Variation 2: Leak detection trays of different sizes Depending on the size of the leak detector chamber, leak detection trays can be designed in various sizes, such as small (for benchtop leak detectors), standard (for vertical leak detectors), and large (for custom leak detection systems). The tray size of the leak detection basket frame should be adjusted accordingly.

[0061] Variation 3: Alternative to the limiting structure In addition to the movable side beam, the limiting structure can also be a spring clip, a rotating baffle, a magnetic block, or an elastic strap, as long as it can prevent the leak detection tray from sliding out.

[0062] Variant 4: Automated Extension In mass production scenarios, this tooling can be used with automated robotic arms to achieve automatic tray loading, automatic can pressing, and automatic loading and unloading, further improving efficiency.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions for some or all of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A leak detection fixture for a hermetically sealed circuit, characterized in that, include: At least one leak detection tray is provided for carrying the circuit to be leaked, and the bottom and / or sidewalls of the leak detection tray are provided with a gas flow structure to facilitate the discharge or entry of gas during the leak detection process; And a leak detection basket frame for simultaneously accommodating multiple leak detection trays, the leak detection basket frame having a multi-layer tray structure, each tray being used to place one leak detection tray, and the leak detection basket frame having a detachable or closable limiting structure to prevent the leak detection trays from sliding out during transfer or pressurization.

2. The leak detection fixture for hermetic encapsulated circuits according to claim 1, characterized in that, The bottom of the leak detection tray is provided with multiple leak detection tray air holes (1), and the four corners of the leak detection tray are respectively provided with leak detection tray fixing holes (2) for installing pick-up and drop auxiliary components or fixing components.

3. The leak detection fixture for the hermetic packaged circuit according to claim 1, characterized in that, The leak detection basket includes: Handle (4) is used for lifting and placing the leak detection basket frame as a whole; Multiple trays (5) are used to support each leak detection tray respectively; The fixed side beam (6) is fixedly connected to the support plate (5); The movable side beam (9), as the limiting structure, is inserted into or removed from the fixed side beam (6) to restrict the leak detection tray from sliding off the tray (5) in the inserted state.

4. The leak detection fixture for the hermetic packaged circuit according to claim 3, characterized in that, The tray (5) is provided with air holes for the flow of gas during the pressure tank and leak detection process; the tray (5) is fixedly connected to the fixed side beam (6) by angle aluminum (7) and fastening screws (8).

5. The leak detection fixture for hermetic encapsulated circuits according to claim 1, characterized in that, The external dimensions of the leak detection basket are matched with the internal dimensions of the pressure tank, so that a preset gap is maintained between the leak detection basket and the tank wall after the leak detection basket is installed in the pressure tank. The number of layers in the height direction of the leak detection basket and the number of trays in each layer are determined according to the volume of the pressure tank and the volume of the leak detector cavity.

6. A surface treatment method for a leak detection tray, used in the leak detection fixture for the hermetic packaged circuit as described in claim 1, characterized in that, Includes the following steps: The leak detection tray is subjected to water washing, acid washing, alkaline etching, ultrasonic water washing and drying in sequence; The dried leak detection tray is coated or oxidized to form a non-adsorbent gas layer on its surface.

7. A method for leak detection using the leak detection fixture for hermetic encapsulated circuits as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Place the circuit to be tested into multiple leak detection trays, then place each leak detection tray into the respective trays of the leak detection basket frame, and fix them in place by the limiting structure; Step 2: Place the leak detection basket rack containing multiple leak detection trays into the pressure tank for pressure treatment; Step 3: After the pressure tank is completed, remove the leak detection basket frame from the pressure tank as a whole, and then remove the leak detection trays one by one from the leak detection basket frame. Place each leak detection tray into the cavity of the helium mass spectrometer leak detector for leak rate detection. Step 4: After the leak test is completed, remove the circuit from the leak test tray.

8. The method according to claim 7, characterized in that, In step two, the pressure tank treatment includes: sealing the pressure tank, evacuating it, filling it with helium and pressurizing it to a specified pressure value, and maintaining it for a specified time.

9. The method according to claim 7, characterized in that, In step three, after the leak detection tray is placed into the cavity of the helium mass spectrometer leak detector, the leak detector draws air through the air hole (1) of the leak detection tray to detect the flow rate of helium gas released from inside the circuit.

10. The method according to claim 7, characterized in that, The number of leak detection trays placed simultaneously in the leak detection basket is determined based on the volume of the pressure tank and the volume of the leak detector cavity, so that the number of circuits processed in a single pressure tank operation is greater than the number of circuits processed in a single leak detection operation.

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