A window breaking device for wafer level infrared focal plane detector

Abstract

The utility model relates to the technical field of detector, disclose a kind of wafer level infrared focal plane detector's window breaking device, suitable for separating the chip and cap wafer of wafer level infrared focal plane detector, including heating unit, accommodating unit, guide unit;Accommodating unit includes two push plates placed on the upper surface of heating unit;Two push plates are mutually horizontal close or far away under the guidance of guide unit;One of push plate is fixed with push block;Chip is located on the upper surface of heating unit and between two push plates;Push block is used to contact cap wafer when two push plates are close and push cap wafer from chip, the utility model can make chip and cap wafer separate by one side push plate and the push block of other side, and chip and cap wafer cannot be caused by debris pollution.

Description

Technical Field

[0001] This utility model relates to the field of detector technology, specifically a window-breaking device for a wafer-level infrared focal plane detector. Background Technology

[0002] A wafer-level packaged infrared focal plane detector consists of a chip and a cap wafer. The chip is also known as a memswafer, and the cap wafer is also known as a cap wafer. Wafer-level packaged infrared focal plane detectors can be used in security monitoring, industrial temperature measurement, and assisted driving. After testing the wafer-level packaged infrared focal plane detector, the test report often shows bad spots. In order to find the cause of the bad spots, it is necessary to perform windowing treatment on the wafer-level packaged infrared focal plane detector.

[0003] In existing technologies, breaking windows in wafer-level packaged infrared focal plane detectors often involves cutting the cap wafer, such as by laser ablation, to create a small hole at the location of the bad spot on the cap wafer, thus breaking the window. However, during this process, silicon shavings can adhere to the surfaces of the chip and the cap wafer, which can affect subsequent defect observation and make it impossible to accurately identify the cause of the bad spot. Therefore, there is an urgent need for a window breaking device that can prevent silicon shavings from adhering to the chip and the cap wafer.

[0004] Therefore, the technical problem to be solved in this case is: how to break the window to protect the chip and the capped wafer. Utility Model Content

[0005] To address the aforementioned technical problems, this utility model provides a window-breaking device for a wafer-level infrared focal plane detector. This device places the wafer-level infrared focal plane detector on a heating unit and heats it. Then, it drives two push plates away from each other, positioning the detector between the two push plates. At this point, the push block and the push plate on the other side contact the opposite side of the detector. Finally, driving the two push plates closer together separates the chip and the cap wafer. The push block and positioning block prevent debris from separating the cap wafer and chip from contaminating the chip or cap wafer. Furthermore, the guiding unit ensures the direction of movement of the support frame, preventing vertical deviation of the receiving unit and thus improving the window-breaking effect.

[0006] The technical solution of this utility model is:

[0007] A window-breaking device for a wafer-level infrared focal plane detector is suitable for separating the chip and cap wafer of the wafer-level infrared focal plane detector. It includes a heating unit, a receiving unit, and a guiding unit. The receiving unit includes two push plates placed on the upper surface of the heating unit. The two push plates are horizontally close to or far apart from each other under the guidance of the guiding unit. A push block is fixed on one of the push plates. The chip is located on the upper surface of the heating unit and between the two push plates. The push block is used to contact the cap wafer and push the cap wafer off the chip when the two push plates are close together.

[0008] Preferably, the push block protrudes from the push plate, and the distance between the push block protruding from the push plate is greater than the distance between the outer peripheral wall of the chip and the outer peripheral wall of the cap wafer.

[0009] Preferably, the vertical distance between the bottom of the push block and the top of the chip is 0 to 200 μm. More preferably, the vertical distance between the bottom of the push block and the top of the chip can be 0 μm, 100 μm, or 200 μm.

[0010] Preferably, the upper surfaces of both push plates are fixed with vertically arranged support frames, and a handle is provided on one side of the support frame. The handle is located on the side of the support frame away from the other support frame, and the two support frames are horizontally approaching or moving away from each other under the guidance of the guide unit.

[0011] Preferably, the guide unit includes two guide rods, and the support frame is provided with horizontally arranged through holes, with each through hole corresponding to one of the guide rods. The guide rods pass through the through holes, and the two guide rods are located above and below the handle, respectively.

[0012] Preferably, the guide rod is provided with limiting blocks at both ends, and the outer diameter of the limiting blocks is larger than the inner diameter of the through hole.

[0013] Preferably, a spring is provided on the outer peripheral wall of the guide rod, the spring is located between symmetrically arranged support frames, and the two ends of the spring are respectively connected to the opposite side of the symmetrically arranged support frames.

[0014] Preferably, the heating unit is a heating plate.

[0015] One of the above-described technical solutions of this utility model has at least one of the following advantages or beneficial effects:

[0016] This invention places a wafer-level infrared focal plane detector on a heating unit and heats the detector. Two push plates are then driven away to position the detector between them. At this point, the push block and the other push plate contact the opposite side of the detector. Finally, the two push plates are driven closer together to separate the chip and the cap wafer. The push block and positioning block prevent debris from separating the chip and cap wafer from contaminating the chip or cap wafer. Furthermore, the guiding unit ensures the direction of movement of the support frame, preventing vertical deviation of the receiving unit and thus improving the window-breaking effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0018] Figure 2 This is a front view of Embodiment 1 of the present invention without a wafer-level infrared focal plane detector and a heating unit;

[0019] Figure 3 This is a side view of the support frame with push block according to Embodiment 1 of this utility model;

[0020] Figure 4 This is a schematic diagram of the guide rod in Embodiment 1 of this utility model.

[0021] The reference numerals for each of the attached figures are as follows:

[0022] 1. Heating unit;

[0023] 2. Receiving unit; 21. Push plate; 21a. First push plate; 21b. Second push plate; 22. Push block; 23. Support frame; 24. Handle; 25. Through hole;

[0024] 3. Guide unit; 31. Guide rod; 32. Limiting block; 33. Spring;

[0025] 4. Wafer-level infrared focal plane detector; 41. Capped wafer; 42. Chip. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Example 1

[0028] Please see Figure 1-4 A window-breaking device for a wafer-level infrared focal plane detector is provided, suitable for separating the chip 42 and the cap wafer 41 of the wafer-level infrared focal plane detector 4. The device includes a heating unit 1, a receiving unit 2, and a guiding unit 3. The receiving unit 2 includes two push plates 21 placed on the upper surface of the heating unit 1. The two push plates 21 are horizontally close to or far apart from each other under the guidance of the guiding unit 3. A push block 22 is fixed on one of the push plates 21. The chip 42 is located on the upper surface of the heating unit 1 and between the two push plates 21. The push block 22 is used to contact the cap wafer 41 when the two push plates 21 are close together and push the cap wafer 41 away from the chip 42.

[0029] It should be noted that in this embodiment, the chip 42 and the cap wafer 41 are fused together under high temperature conditions. The upper surface of the chip 42 and the lower surface of the cap wafer 41 contain metal, which will fuse together under high temperature conditions. The window of the wafer-level infrared focal plane detector 4 is broken because bad spots were found when testing the wafer-level infrared focal plane detector 4, and the cause of the bad spots needs to be observed and analyzed.

[0030] For ease of explanation, the two push plates 21 are referred to as the first push plate 21a and the second push plate 21b, wherein the push block 22 is fixed on the first push plate 21a.

[0031] In actual operation, the operator places the wafer-level infrared focal plane detector 4 on the heating unit 1 and heats it through the heating unit 1. When the preset temperature is reached, the operator drives the two push plates 21 to move away from each other, moves the receiving unit 2, so that the wafer-level infrared focal plane detector 4 is positioned between the two push plates 21. Then, the operator drives the two push plates 21 to move closer to each other until the second push plate 21b and one side of the chip 42 are in contact or the push block 22 and one side of the cap wafer 41 are in contact, and pushes the wafer-level infrared focal plane detector 4. The heating unit 1 moves, causing the pusher block 22 to contact one side of the capped wafer 41 or the second pusher plate 21b to contact one side of the chip 42 to clamp both sides of the chip 42. It should be noted that the side of the chip 42 and the side of the capped wafer 41 referred to here are the opposite sides of the wafer-level infrared focal plane detector 4, and the movement of the wafer-level infrared focal plane detector 4 on the heating unit 1 will not affect the wafer-level infrared focal plane detector 4. Then, force is applied to the two pusher plates 21 respectively, specifically in the direction of mutual approach. At this time, the pusher block 22 has a force on the capped wafer 41. The second pusher plate 21b exerts another push on the chip 42. These two pushers are in opposite directions, causing the capped wafer 41 and the chip 42 to separate. During separation, the first pusher plate 21a also acts as a limiting force. Specifically, after the capped wafer 41 and the chip 42 separate, the operator will apply force to the pusher plate 21, causing the first pusher plate 21a to press against the other side of the chip 42. This means that the two pusher plates 21 will eventually clamp the chip 42, thus achieving the limiting function. Finally, the operator uses tweezers to remove the chip 42 into the cooling metal box. Cooling can also be achieved through other methods. After cooling, the sample can be observed using an optical microscope. This method of separation prevents the generated debris from contaminating the chip 42 and the cap wafer 41. The debris mainly refers to silicon chips. Therefore, when observing the chip 42 later, the contamination of the debris can be prevented, making the observation results more accurate and the analysis of the cause more precise. On the other hand, the guide unit 3 can ensure that the push plate 21 moves horizontally, thereby preventing the two push plates 21 from shifting when the staff applies force to the push plate 21, thus ensuring the separation effect.

[0032] Preferably, the push block 22 protrudes from the push plate 21, and the distance by which the push block 22 protrudes from the push plate 21 is greater than the distance between the outer peripheral wall of the chip 42 and the outer peripheral wall of the cap wafer 41.

[0033] In the above design, by making the distance of the push block 22 protruding from the first push plate 21a greater than the distance between the outer peripheral wall of the chip 42 and the outer peripheral wall of the cap wafer 41, it can be ensured that only the second push plate 21b and the push block 22 are in contact with the wafer-level infrared focal plane detector 4 when clamping the wafer-level infrared focal plane detector 4. This prevents the two push plates 21 from clamping the wafer-level infrared focal plane detector 4, which would cause the push block 22 to be unable to push the cap wafer 41 off the chip 42.

[0034] Preferably, the vertical distance between the bottom of the push block 22 and the top of the chip 42 is 0 to 200 μm.

[0035] In this embodiment, the vertical distance between the bottom of the pusher block 22 and the top of the chip 42 is 0 μm. That is, when the chip 42 is placed flat on the heating unit 1, the height of the chip 42 matches the height of the first pusher plate 21a. However, the height of the first pusher plate 21a needs to be greater than the height of one chip 42 and less than the total height of the wafer-level infrared focal plane detector 4. This ensures that the pusher block 22 can push the capped wafer 41 away from the chip 42. In other words, the pusher block 22 will not contact the chip 42. When the vertical distance between the bottom of the pusher block 22 and the top of the chip 42 is 200 μm, it can maximize the guarantee that the pusher block 22 will not contact the chip 42. That is, it will only contact the capped wafer 41, thereby improving the fault tolerance of the operation.

[0036] Preferably, the upper surfaces of the two push plates 21 are each fixed with a vertically arranged support frame 23. A handle 24 is provided on one side of the support frame 23. The handle 24 is located on the side of the support frame 23 away from the other support frame 23. The two support frames 23 are horizontally close to or away from each other under the guidance of the guide unit 3.

[0037] In the above design, the handle 24 allows the operator to easily apply force, that is, to drive the support frame 23 to move. The operator can either move the support frames 23 away from each other or move the two support frames 23 away from each other, so that the wafer-level infrared focal plane detector 4 can be placed in the placement area better. The operator can also move the two support frames 23 closer to each other, so that the chip 42 and the cap wafer 41 can be separated. The handle 24 is convenient for the operator to operate.

[0038] Preferably, the guide unit 3 includes two guide rods 31, and the support frame 23 is provided with horizontally arranged through holes 25. The through holes 25 and the guide rods 31 are arranged in a one-to-one correspondence. The guide rods 31 pass through the through holes 25, and the two guide rods 31 are located above and below the handle 24, respectively.

[0039] In this embodiment, the guide rod 31 passes through the through hole 25. Since the two support frames 23 are symmetrically arranged, one guide rod 31 passes through the corresponding two through holes 25 of the two support frames 23. Therefore, the two guide rods 31 are arranged horizontally and parallel to each other, and are located above and below the handle 24 respectively. The two guide rods 31 can better restrict the movement of the support frame 23 and avoid the offset between the two support frames 23 in various directions. That is to say, the two support frames 23 can be restricted to move on a plane by the two parallel guide rods 31, thereby ensuring that the force direction of the chip 42 and the cap wafer 41 is parallel, thereby improving the separation effect.

[0040] Preferably, the guide rod 31 is provided with limiting blocks 32 at both ends, and the outer diameter of the limiting blocks 32 is larger than the inner diameter of the through hole 25.

[0041] Through the above design, the limiting block 32 can prevent the support frame 23 from detaching from both ends of the guide rod 31 when the operator moves the two support frames 23 away. It can not only limit the movement but also prevent fooling. It is not only convenient for the operator to use, but also easier for the operator to use.

[0042] Preferably, a spring 33 is provided on the outer peripheral wall of the guide rod 31. The spring 33 is located between the symmetrically arranged support frames 23, and the two ends of the spring 33 are respectively connected to the opposite side of the symmetrically arranged support frames 23.

[0043] With the above design, when not in use, the window breaking device can maintain a certain distance between the two support frames 23 under the design of spring 33. However, when it is needed, the operator operates the two support frames 23 to move away from each other. At this time, the two support frames 23 need to be moved away from each other to a certain distance until at least the entire wafer-level infrared focal plane detector 4 can be placed. Therefore, the operator needs to drive the two support frames 23 away from each other as much as possible. However, since the two support frames 23 are spaced a certain distance apart under the action of spring 33, the operator does not need to drive the two support frames 23 to move away from each other by a longer distance, which improves the ease of use of the window breaking device. After use, spring 33 will bring the two support frames 23 closer together to the initial distance through elastic recovery, and no further operation by the operator is required.

[0044] Preferably, heating unit 1 is a heating plate.

[0045] In this embodiment, the heating unit 1 can be a heating plate, specifically a ceramic heating plate. The wafer-level infrared focal plane detector 4 can be placed flat on the heating unit 1, and the heating unit 1 can achieve a preset temperature to heat the wafer-level infrared focal plane detector 4, thereby facilitating the subsequent window breaking operation of the two support frames 23.

[0046] It should be noted that in this embodiment, the temperature of the heating unit 1 is set to 320-400°C. This temperature range makes it easier to separate the high-temperature fused metal between the chip 42 and the cap wafer 41, thus facilitating the operation of the support frame 23 by the operator to separate the chip 42 and the cap wafer 41. Specifically, the heating unit 1 is set to a temperature of 320-400°C and heated for 5 minutes within this temperature range. The wafer-level infrared focal plane detector 4 is then placed on it and heated for 30-50 seconds. Then, the two support frames 23 are used to break the window of the wafer-level infrared focal plane detector 4.

[0047] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A window-breaking device for a wafer-level infrared focal plane detector, suitable for separating the chip and cap wafer of a wafer-level infrared focal plane detector, characterized in that, The device includes a heating unit, a receiving unit, and a guiding unit. The receiving unit includes two push plates placed on the upper surface of the heating unit. The two push plates move horizontally closer or further apart under the guidance of the guiding unit. A push block is fixed on one of the push plates. The chip is located on the upper surface of the heating unit and between the two push plates. The push block is used to contact the capped wafer and push the capped wafer away from the chip when the two push plates are close together.

2. The window-breaking device for a wafer-level infrared focal plane detector according to claim 1, characterized in that, The pusher block protrudes from the pusher plate, and the distance by which the pusher block protrudes from the pusher plate is greater than the distance between the outer peripheral wall of the chip and the outer peripheral wall of the cap wafer.

3. The window-breaking device for a wafer-level infrared focal plane detector according to claim 1, characterized in that, The vertical distance between the bottom of the push block and the top of the chip is 0 to 200 μm.

4. The window-breaking device for a wafer-level infrared focal plane detector according to claim 1, characterized in that, Both push plates have vertically arranged support frames fixed on their upper surfaces. Each support frame has a handle on one side, which is located on the side of the support frame away from the other support frame. The two support frames move horizontally closer to or further away from each other under the guidance of the guide unit.

5. The window-breaking device for a wafer-level infrared focal plane detector according to claim 4, characterized in that, The guide unit includes two guide rods. The support frame has horizontally arranged through holes, and the through holes correspond one-to-one with the guide rods. The guide rods pass through the through holes, and the two guide rods are located above and below the handle, respectively.

6. The window-breaking device for a wafer-level infrared focal plane detector according to claim 5, characterized in that, The guide rod is provided with limiting blocks at both ends, and the outer diameter of the limiting blocks is larger than the inner diameter of the through hole.

7. The window-breaking device for a wafer-level infrared focal plane detector according to claim 5, characterized in that, A spring is provided on the outer peripheral wall of the guide rod. The spring is located between the symmetrically arranged support frames, and the two ends of the spring are respectively connected to the opposite side of the symmetrically arranged support frames.

8. The window-breaking device for a wafer-level infrared focal plane detector according to claim 1, characterized in that, The heating unit is a heating plate.

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