Low-temperature test box and low-temperature test method for integrated circuit board

Abstract

The invention discloses a low-temperature test box and a low-temperature test method for an integrated circuit board, and belongs to the technical field of low-temperature performance test of the integrated circuit board. The method is used for solving at least one problem that in the prior art, a low-temperature test box material easily generates microcracks in a low-temperature environment, so that heat insulation performance is reduced, and external temperature interference cannot be effectively isolated. According to the low-temperature test box, a test box body comprises an outer protective shell and a main heat insulation layer which are sequentially stacked from outside to inside; the main heat insulation layer comprises a hard heat insulation outer layer, a vacuum heat insulation plate and an aerogel felt layer which are sequentially stacked from outside to inside. The method comprises the following steps: cooling a first integrated circuit board to a first temperature for the first time, and then carrying out heat preservation for the first time; carrying out secondary cooling on the first integrated circuit board after primary heat preservation to a second temperature, and then carrying out secondary heat preservation; in the step 3 and the step 4, temperature data of the first integrated circuit board are collected through an infrared temperature detector. The method can be used for low-temperature testing of the integrated circuit board.

Description

Technical Field

[0001] This invention belongs to the field of low-temperature performance testing technology for integrated circuit boards, and in particular, a low-temperature test chamber and a low-temperature test method for integrated circuit boards. Background Technology

[0002] The low-temperature test chamber for integrated circuit boards is a key testing equipment in the fields of semiconductor manufacturing and electronic equipment research and development. Its core function is to simulate a stable low-temperature environment from -40℃ to room temperature to ensure the cold resistance, electrical performance stability and reliability of integrated circuit boards (including chips and component solder joints).

[0003] The existing equipment adopts a three-layer structure of "outer shell + insulation layer + inner liner". The insulation layer is mostly made of traditional materials such as polyurethane foam and rock wool, which are fixed by filling or bonding.

[0004] However, in low-temperature environments, materials are prone to microcracks, resulting in decreased thermal insulation performance and an inability to isolate external temperature interference. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a low-temperature test chamber and a low-temperature test method for integrated circuit boards, in order to solve at least one of the problems in the prior art where the material of the low-temperature test chamber is prone to microcracks under low-temperature environments, resulting in a decrease in thermal insulation performance and an inability to effectively isolate external temperature interference.

[0006] The objective of this invention is mainly achieved through the following technical solutions.

[0007] In a first aspect, the present invention provides a low-temperature test chamber for integrated circuit boards, comprising a test chamber body, a cooling unit for cooling the test chamber body, and a circuit board mounting base disposed on the bottom wall of the test chamber body.

[0008] The test chamber consists of an outer protective shell and a main insulation layer stacked from the outside to the inside;

[0009] The main insulation layer consists of a rigid outer insulation layer, a vacuum insulation panel, and an aerogel felt layer, which are stacked sequentially from the outside to the inside.

[0010] Furthermore, the thickness of the rigid thermal insulation outer layer is 45mm to 55mm.

[0011] Furthermore, the thickness of the vacuum insulation panel is 18mm to 23mm.

[0012] Furthermore, the thickness of the aerogel felt layer is 8mm to 12mm.

[0013] Furthermore, the low-temperature test chamber also includes a mounting sleeve for installing the cooling unit. The mounting sleeve is fitted onto the outer wall of the cooling unit and is sealed to the side wall of the test chamber.

[0014] Furthermore, the mounting sleeve includes a sleeve body and a seal disposed at the connection between the sleeve body and the side wall of the test chamber.

[0015] Furthermore, the sealing element includes an elastic sealing ring and a sealing adhesive layer, with the elastic sealing ring nested in the contact area between the sleeve and the side wall of the test chamber;

[0016] The sealant layer fills the gap between the elastic sealing ring and the sleeve, and the side wall of the test chamber.

[0017] Secondly, the present invention also provides a low-temperature testing method for integrated circuit boards, comprising the following steps:

[0018] Step 1: Provide a test chamber, and extend the infrared thermometer's acquisition end through the side wall of the test chamber and into the test chamber;

[0019] Step 2: Place the first integrated circuit board on the circuit board mounting bracket of the test chamber;

[0020] Step 3: Activate the cooling unit to cool the first integrated circuit board inside the test chamber to the first temperature, and then maintain the temperature.

[0021] Step 4: After the first heat preservation, the first integrated circuit board is cooled to a second temperature and then subjected to a second heat preservation.

[0022] During the cooling and heat preservation processes in steps 3 and 4, temperature data of the first integrated circuit board is collected using an infrared thermometer.

[0023] Furthermore, step 3 includes the following steps:

[0024] Cool to 2℃ to -3℃ at a rate of 4℃ / min to 6℃ / min, and hold for 20min to 40min.

[0025] Furthermore, step 4 includes the following steps:

[0026] Cool to -40℃ at a rate of 1.5℃ / min to 2.5℃ / min, and hold for 45 min to 75 min.

[0027] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0028] A) The low-temperature test chamber for integrated circuit boards provided by this invention has a composite structure as its main insulation layer (i.e., a rigid outer insulation layer, a vacuum insulation board, and an aerogel felt layer). The rigid outer insulation layer is the initial insulation layer, which has a low cost. The vacuum insulation board is the main insulation layer, and the aerogel felt layer is a flexible material that can adapt to thermal expansion and contraction at low temperatures, effectively reducing structural damage caused by temperature changes. The synergistic effect of the three can significantly improve the overall insulation performance. Even at a low temperature of -40℃, the internal temperature fluctuation can still be maintained at less than ±0.5℃, thereby effectively solving the problem in the prior art where the material of the low-temperature test chamber is prone to microcracks, leading to a decrease in insulation performance.

[0029] B) The low-temperature test chamber for integrated circuit boards provided by the present invention, through the setting of the outer protective shell, is used to support the overall structure of the low-temperature test chamber, which can effectively protect the main insulation layer from external physical damage, such as collisions and scratches. At the same time, the outer protective shell also has waterproof and dustproof functions, thereby further extending the service life of the test chamber.

[0030] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0031] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0032] Figure 1 This is a schematic diagram of the structure of a low-temperature test chamber for integrated circuit boards provided in Embodiment 1 of the present invention;

[0033] Figure 2 This is a schematic diagram of the mounting sleeve in a low-temperature test chamber for an integrated circuit board provided in Embodiment 1 of the present invention;

[0034] Figure 3a This is a schematic diagram of the circuit board mounting bracket position in step 5 of the low-temperature testing method for integrated circuit boards provided in Embodiment 2 of the present invention.

[0035] Figure 3b This is a schematic diagram of the circuit board mounting bracket position in step 7 of the low-temperature testing method for integrated circuit boards provided in Embodiment 2 of the present invention.

[0036] Figure 3c This is a schematic diagram of the circuit board mounting bracket position in step 9 of the low-temperature testing method for integrated circuit boards provided in Embodiment 2 of the present invention.

[0037] Figure 3d This is a schematic diagram of the circuit board mounting position in step 10 of the low-temperature testing method for integrated circuit boards provided in Embodiment 2 of the present invention.

[0038] Figure label:

[0039] 1-Cooling unit; 2-Infrared thermometer; 3-Outer protective shell; 4-Rigid heat insulation outer layer; 5-Vacuum heat insulation board; 6-Aerogel felt layer; 7-Shell body; 8-Elastic sealing ring; 9-Sealing adhesive layer; 10-Circuit board mounting plate; 11-Drive shaft; 12-First baffle; 13-Second baffle; 14-First mounting groove; 15-Second mounting groove; 16-First integrated circuit board; 17-Second integrated circuit board; 18-First sealing sheet; 19-Second sealing sheet. Detailed Implementation

[0040] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0041] Example 1

[0042] This embodiment provides a low-temperature testing chamber for integrated circuit boards, see [link to documentation]. Figure 1 It includes a test chamber, a cooling unit 1 for cooling the test chamber, and a circuit board mounting base located on the bottom wall of the test chamber. The test chamber includes an outer protective shell 3 and a main insulation layer stacked sequentially from the outside to the inside.

[0043] Specifically, the structure of the main insulation layer includes, from the outside to the inside, a rigid insulation outer layer 4 (e.g., rigid polyurethane foam), a vacuum insulation board 5, and an aerogel felt layer 6, stacked sequentially.

[0044] Compared with the prior art, the low-temperature test chamber for integrated circuit boards provided in this embodiment has the following advantages: First, the main insulation layer is a composite structure (i.e., a rigid outer insulation layer 4, a vacuum insulation board 5, and an aerogel felt layer 6). The rigid outer insulation layer 4 is the initial insulation layer, which has a lower cost. The vacuum insulation board is the main insulation layer, and the aerogel felt layer 6 is a flexible material that can adapt to thermal expansion and contraction at low temperatures, effectively reducing structural damage caused by temperature changes. The synergistic effect of the three can significantly improve the overall insulation performance. Even in a low-temperature environment of -40℃, the internal temperature fluctuation can still be maintained at less than ±0.5℃, thereby effectively solving the problem that the materials of the low-temperature test chamber in the prior art are prone to microcracks, which leads to a decrease in insulation performance.

[0045] On the other hand, the outer protective shell 3 is used to support the overall structure of the low-temperature test chamber, which can effectively protect the main insulation layer from external physical damage, such as collisions and scratches. At the same time, the outer protective shell also has waterproof and dustproof functions, which can further extend the service life of the test chamber.

[0046] For example, the thickness of the rigid thermal insulation outer layer 4 is 45 mm to 55 mm (e.g., 50 mm). The rigid thermal insulation outer layer 4 has good initial thermal insulation performance and low cost.

[0047] The thickness of the vacuum insulation panel 5 is 18mm to 23mm (e.g., 20mm), the vacuum degree in the vacuum insulation panel 5 is ≤0.1Pa, and the thermal conductivity is ≤0.004W / m·K.

[0048] The thickness of the aerogel felt layer 6 is 8 mm to 12 mm (e.g., 10 mm).

[0049] To address the impact of the cooling unit 1 on the sealing and insulation of the test chamber, the aforementioned low-temperature test chamber for integrated circuit boards also includes a mounting sleeve for installing the cooling unit 1. (See [link to relevant documentation]). Figure 2 The mounting sleeve is fitted onto the outer wall of the cooling unit 1 and is sealed to the side wall of the test chamber.

[0050] Specifically, the mounting sleeve includes a sleeve body 7 and a seal located at the connection between the sleeve body 7 and the side wall of the test chamber.

[0051] The sleeve 7 is made of a high-strength material with low thermal conductivity, such as stainless steel or a special alloy. Its shape is adapted to the outer wall of the cooling unit 1, and it can be tightly fitted onto the outer wall of the cooling unit 1 to fix and protect the cooling unit 1.

[0052] The sealing element includes an elastic sealing ring 8 and a sealing adhesive layer 9. The elastic sealing ring 8 is nested in the contact area between the sleeve 7 and the side wall of the test chamber, and has good elasticity and sealing performance, effectively preventing outside air and moisture from entering the interior of the test chamber. The sealing adhesive layer 9 fills the gaps between the elastic sealing ring 8, the sleeve 7, and the side wall of the test chamber, further enhancing the sealing effect and ensuring that the airtightness and thermal insulation of the test chamber are not affected by the cooling unit 1.

[0053] It is worth noting that in the existing technology, during the low-temperature testing of integrated circuit boards, after the previous integrated circuit board has been tested, the temperature is still low. The tester cannot manually remove the tested integrated circuit board at -40℃. Therefore, it is necessary to wait for the temperature inside the test chamber to return to normal before opening the test chamber, taking out the tested integrated circuit board, and then putting in the next integrated circuit board. This obviously greatly reduces the efficiency of low-temperature testing of integrated circuit boards and cannot guarantee that the test conditions of multiple integrated circuit boards are consistent, affecting the accuracy of low-temperature testing of integrated circuit boards.

[0054] Therefore, for the structure of the circuit board mounting bracket, see [link to relevant documentation]. Figure 1 The test chamber includes a circuit board mounting plate 10, a drive shaft 11, a first baffle 12, and a second baffle 13. A turntable mounting hole is provided on the bottom wall of the test chamber. The circuit board mounting plate 10 is rotatably connected to the turntable mounting hole through the drive shaft 11. A first mounting groove 14 and a second mounting groove 15 for accommodating integrated circuit boards are provided on the circuit board mounting plate 10. The side wall of the first mounting groove 14 located in front is defined as the first side wall, the side wall of the first mounting groove 14 located behind is defined as the second side wall, the side wall of the second mounting groove 15 located in front is defined as the third side wall, and the side wall of the second mounting groove 15 located behind is defined as the fourth side wall. The first baffle 12 is provided on the second side wall, and the second baffle 13 is provided on the fourth side wall.

[0055] It is worth noting that when the first mounting groove 14 and the second mounting groove 15 pass through the bottom wall of the test chamber, the gap between the first mounting groove 14, the second mounting groove 15 and the bottom wall of the test chamber may cause the loss of gas and heat, affecting the sealing and heat preservation of the test chamber. Therefore, the test chamber also includes a first sealing plate 18 and a second sealing plate 19. The first sealing plate 18 is provided on one side of the rotating plate mounting hole, and the second sealing plate 19 is provided on the other side of the rotating plate mounting hole.

[0056] For example, the cross-sectional shapes of the first sealing plate 18 and the second sealing plate 19 are both arc-shaped. The arc length of the first sealing plate 18 is greater than the width of the first mounting groove 14, and the arc length of the second sealing plate 19 is greater than the width of the second mounting groove 15. Thus, when the first mounting groove 14 and the second mounting groove 15 rotate to a position contacting the bottom wall of the test chamber, the first sealing plate 18 and the second sealing plate 19 can respectively tightly fit the sides of the first mounting groove 14 and the second mounting groove 15, effectively blocking the loss of gas and heat, thereby significantly reducing the adverse effects on the sealing and insulation performance of the test chamber caused by gaps. Simultaneously, the arc-shaped baffles can better adapt to the rotation trajectory of the circuit board mounting plate 10, ensuring that it remains tightly fitted with the turntable mounting groove during rotation, further improving the sealing effect.

[0057] Example 2

[0058] This embodiment provides a low-temperature testing method for integrated circuit boards, using the low-temperature testing chamber for integrated circuit boards provided in Embodiment 1.

[0059] Compared with the prior art, the beneficial effects of the low-temperature testing method for integrated circuit boards provided in this embodiment are basically the same as the beneficial effects of the low-temperature testing chamber for integrated circuit boards provided in Embodiment 1, and will not be described in detail here.

[0060] Specifically, the above-mentioned low-temperature testing method includes the following steps:

[0061] Step 1: Provide a test chamber, and extend the acquisition end of the infrared thermometer 2 through the side wall of the test chamber into the test chamber;

[0062] Step 2: Place the first integrated circuit board 16 on the circuit board mounting bracket of the test chamber;

[0063] Step 3: Activate cooling unit 1 to cool the first integrated circuit board 16 inside the test chamber to the first temperature and then maintain the temperature.

[0064] Step 4: After the first heat preservation, the first integrated circuit board 16 is cooled to a second temperature and then subjected to a second heat preservation.

[0065] During the cooling and heat preservation processes in steps 3 and 4 above, the temperature data of the first integrated circuit board 16 is collected by the infrared thermometer 2.

[0066] It should be noted that in step 3 above, the initial cooling to the first temperature followed by heat preservation can eliminate the temperature stress difference between the first integrated circuit board 16 and the circuit board mounting base through pre-cooling and heat preservation, thereby effectively reducing poor contact or structural damage caused by thermal expansion and contraction, and improving test stability and data reliability. In step 4 above, the secondary cooling to the second temperature followed by heat preservation can further simulate the working state of the integrated circuit board in extreme low temperature environments, thereby more realistically reflecting its performance in practical applications.

[0067] For example, step 3 above includes the following steps:

[0068] Cool to 2°C to -3°C (e.g., 0°C) at a rate of 4°C / min to 6°C / min (e.g., 5°C / min) and hold for 20 min to 40 min (e.g., 30 min).

[0069] Step 4 above includes the following steps:

[0070] Cool to -40°C at a rate of 1.5°C / min to 2.5°C / min (e.g., 2.0°C / min) and hold for 45 min to 75 min (e.g., 60 min).

[0071] Thus, by controlling the cooling rate and holding time in steps 3 and 4 above, the temperature field distribution of the first integrated circuit board 16 is made uniform at each stage, effectively reducing local overcooling or thermal stress concentration. This reduces the occurrence of material micro-cracks or solder joint failures caused by excessive temperature gradients, ensuring the structural integrity and electrical performance stability of the first integrated circuit board 16 during testing. Simultaneously, the staged cooling and holding process can precisely control the thermal shock intensity, adapting to the heat dissipation characteristics of different packaging types and substrates, further improving the repeatability and accuracy of the test.

[0072] After the first integrated circuit board 16 has been tested, a new integrated circuit board (i.e., the second integrated circuit board 17) needs to be replaced for low-temperature testing.

[0073] Therefore, the following steps are included after step 4 above:

[0074] Step 5: Turn off cooling unit 1 to allow the temperature inside the test chamber to rise to 0℃. See [link / reference] Figure 3a ;

[0075] Step 6: Rotate the circuit board mounting plate 10 counterclockwise. The first mounting slot 14 drives the first integrated circuit board 16 to rotate downward counterclockwise by 25° to 35°. Correspondingly, the second mounting slot 15 rotates upward counterclockwise by 25° to 35°.

[0076] Step 7: Place the second integrated circuit board 17 into the second mounting slot 15, positioned between the second baffle 13 and the bottom of the second mounting slot 15. At this time, the first mounting slot 14 is still inside the test chamber, and the second mounting slot 15 is in place. Due to the setting of the second baffle 13, the second integrated circuit board 17 will not detach from the second mounting slot 15. See [link to relevant documentation]. Figure 3b ;

[0077] Step 8: Continue to rotate the circuit board mounting plate 10 counterclockwise. The first mounting slot 14 will rotate out of the test chamber and the second mounting slot 15 will rotate into the test chamber.

[0078] Step 9: Continue to rotate the circuit board mounting plate 10 counterclockwise. Under the action of gravity, the first integrated circuit board 16 will detach from the first mounting slot 14 and fall into the integrated circuit board collection slot located below the circuit board mounting plate 10, thus completing the removal of the first integrated circuit board 16. See [link to relevant documentation]. Figure 3c ;

[0079] Step 10: Continue to rotate the circuit board mounting plate 10 counterclockwise until the bottom of the second mounting slot 15 is aligned horizontally, completing the placement of the second integrated circuit board 17. See [link / reference] Figure 3d .

[0080] It should be noted that between steps 4 and 5 above, the first integrated circuit board 16 is placed in the first mounting groove 14 and is located between the first baffle 12 and the bottom of the first mounting groove 14, while the second integrated circuit board 17 is not installed in the second mounting groove 15.

[0081] In this way, with the circuit board mounting tray 10, the first baffle 12, and the second baffle 13, the tester can quickly remove the first integrated circuit board 16 and accurately insert the second integrated circuit board 17 without opening the test chamber or waiting for the temperature inside the chamber to return to room temperature. This process not only greatly improves the efficiency of low-temperature testing of integrated circuit boards, but also ensures that each integrated circuit board experiences a basically consistent temperature environment during the test, thereby effectively improving the accuracy and reliability of low-temperature testing of integrated circuit boards.

[0082] It should be noted that since the test chamber only needs to be heated to 0°C to replace the first integrated circuit board 16 and the second integrated circuit board 17, when performing low-temperature testing on the integrated circuit board 17, it is not necessary to lower it from room temperature to 0°C again, but only to perform a single heat preservation.

[0083] This not only shortens the testing cycle of integrated circuit boards but also reduces the impact of repeated temperature fluctuations on the thermal insulation performance of the test chamber, thereby lowering energy consumption and equipment wear. Furthermore, the small temperature fluctuation range during integrated circuit board replacement further ensures the consistency of the testing environment, making test results from different batches more comparable.

[0084] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A low-temperature testing chamber for integrated circuit boards, characterized in that, It includes a test chamber, a cooling unit for cooling the test chamber, and a circuit board mounting base located on the bottom wall of the test chamber. The test chamber includes an outer protective shell and a main insulation layer stacked from the outside to the inside; The main insulation layer comprises, from the outside to the inside, a rigid insulation outer layer, a vacuum insulation panel, and an aerogel felt layer, stacked sequentially.

2. The low-temperature testing chamber for integrated circuit boards according to claim 1, characterized in that, The thickness of the rigid thermal insulation outer layer is 45mm to 55mm.

3. The low-temperature testing chamber for integrated circuit boards according to claim 1, characterized in that, The thickness of the vacuum insulation panel is 18mm to 23mm.

4. The low-temperature testing chamber for integrated circuit boards according to claim 1, characterized in that, The thickness of the aerogel felt layer is 8mm to 12mm.

5. The low-temperature testing chamber for integrated circuit boards according to any one of claims 1 to 4, characterized in that, The low-temperature test chamber also includes a mounting sleeve for installing the cooling unit. The mounting sleeve is fitted onto the outer wall of the cooling unit and is sealed to the side wall of the test chamber.

6. The low-temperature testing chamber for integrated circuit boards according to claim 5, characterized in that, The mounting sleeve includes a sleeve body and a sealing element disposed at the connection between the sleeve body and the side wall of the test chamber.

7. The low-temperature testing chamber for integrated circuit boards according to claim 6, characterized in that, The sealing element includes an elastic sealing ring and a sealing adhesive layer, wherein the elastic sealing ring is nested in the contact area between the sleeve and the side wall of the test chamber; The sealant layer fills the gap between the elastic sealing ring and the sleeve, and the side wall of the test chamber.

8. A low-temperature testing method for integrated circuit boards, characterized in that, Includes the following steps: Step 1: Provide a test chamber, and extend the infrared thermometer's acquisition end through the side wall of the test chamber and into the test chamber; Step 2: Place the first integrated circuit board on the circuit board mounting bracket of the test chamber; Step 3: Activate the cooling unit to cool the first integrated circuit board inside the test chamber to the first temperature, and then maintain the temperature. Step 4: After the first heat preservation, the first integrated circuit board is cooled to a second temperature and then subjected to a second heat preservation. During the cooling and heat preservation processes in steps 3 and 4, temperature data of the first integrated circuit board is collected using an infrared thermometer.

9. The low-temperature testing method for integrated circuit boards according to claim 8, characterized in that, Step 3 includes the following steps: Cool to 2℃ to -3℃ at a rate of 4℃ / min to 6℃ / min, and hold for 20min to 40min.

10. The low-temperature testing method for integrated circuit boards according to claim 8, characterized in that, Step 4 includes the following steps: Cool to -40℃ at a rate of 1.5℃ / min to 2.5℃ / min, and hold for 45 min to 75 min.

Images