A method of unsealing a cover plate solder sealed device

Abstract

The application discloses a method for opening a cover-plate solder sealed device, and belongs to the technical field of opening electronic components, and solves the problem that the mechanical opening along the solder ring easily causes the device body to be broken, which is not conducive to destructive physical analysis and failure analysis. The method comprises the following steps: making the diagonal line of the cover plate perpendicular to the blade of the opening blade; adjusting the height of the device to be opened, so that the blade is aligned with the intersection of the vertical line of the diagonal line of the cover plate and the upper edge of the solder ring; and opening the device to be opened, thereby completing the opening of the cover-plate solder sealed device. The method can be used for opening the cover-plate solder sealed device.

Description

Technical Field

[0001] This invention belongs to the field of electronic component opening technology, and particularly relates to a method for opening a cover plate solder sealing device. Background Technology

[0002] Unpacking is a crucial step in destructive physical analysis (DPA) and failure analysis, and the quality of unpacking directly affects the accuracy of subsequent tests and analysis conclusions.

[0003] GJB4027A-2006 discloses a mechanical opening method for a cover plate solder sealing device: The device substrate to be opened is fixed in place; the opening blade 4 is aligned with the solder ring below the cover plate 2 and inserted along this "line" until the cover plate 2 detaches. (See also...) Figure 1 .

[0004] However, with the cover plate 2 as the reference horizontal plane, the actual solder ring of the device is not always an ideal standard horizontal line. Cutting along this rough "line" of the solder ring with a "one-cut" blade can easily cause problems such as "ceramic chipping" (ceramic body cracking) on ​​the upper surface of the device substrate, damage the internal structure such as the lead frame, introduce contamination, and is not conducive to destructive physical analysis and failure analysis. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a method for opening a cover plate solder sealing device, which solves the problems in the prior art where mechanical opening along the solder ring easily causes the device body to "break porcelain" and is not conducive to destructive physical analysis and failure analysis.

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

[0007] This invention provides a method for opening a cover plate sealing device, the cover plate sealing device comprising a device substrate and a cover plate, the cover plate and the device substrate being sealed together by a solder ring, the method comprising the following steps:

[0008] Step 1: Align the diagonal of the cover plate with the blade of the opening blade;

[0009] Step 2: Adjust the height of the device to be opened so that the blade is aligned with the intersection of the vertical line where the diagonal of the cover plate is located and the upper edge of the solder ring;

[0010] Step 3: Unseal the device to be opened to complete the unsealing of the cover sealing device.

[0011] Furthermore, the above-mentioned opening method uses an opening machine for opening.

[0012] Furthermore, the above-mentioned method of opening the seal includes the following steps:

[0013] Step 1: Place the device to be opened on the sample stage of the opening machine and adjust the orientation of the device so that the diagonal of the cover plate is perpendicular to the blade of the opening blade.

[0014] Step 2: Adjust the height of the sample stage of the opening machine so that the blade is aligned with the intersection of the vertical line where the diagonal of the cover plate is located and the solder ring;

[0015] Step 3: Apply pressure to the blade so that it cuts into the solder ring at the intersection of the vertical line where the cover plate is located diagonally, separating the cover plate from the device substrate, thus completing the unpacking of the device to be unpacked.

[0016] Furthermore, in step 3 above, the following steps are included before applying pressure to the blade:

[0017] Apply pressure toward the sample stage to the device to be opened, so that the relative position of the device to be opened and the sample stage remains unchanged.

[0018] Furthermore, the intersection of the vertical line containing the diagonal of the cover plate and the solder ring is the intersection of the vertical line containing the diagonal of the cover plate and the side of the solder ring closest to the cover plate.

[0019] Furthermore, the initial opening force of the blade is 0.8–2.5 N.

[0020] Furthermore, the aforementioned cover plate sealing device can be a cover plate ceramic sealing device or a cover plate gold-tin sealing device.

[0021] Furthermore, the cover sealing device is a ceramic cover sealing device with an initial opening force of 0.8 to 1.5 N.

[0022] Furthermore, the cover sealing device is a cover ceramic sealing device, with an initial opening force of 0.8N, 1.0N, 1.3N or 1.5N.

[0023] Furthermore, the cover sealing device is a gold-tin cover sealing device, with an initial opening force of 2.0 to 2.5 N.

[0024] Furthermore, the cover sealing device is a cover gold-tin sealing device, with an initial opening force of 2.0N, 2.1N, 2.3N, or 2.5N.

[0025] Furthermore, the cover sealing device is a cover gold-tin sealing device, and step 3 above includes the following steps:

[0026] Step 31: Apply pressure to the cutting edge so that it cuts into the solder ring at the intersection of the vertical line containing the diagonal of the cover plate.

[0027] Step 32: Rotate the device to be opened horizontally around the midpoint of the diagonal. The blade gradually penetrates into the solder ring to rotate and open the device. The cover plate separates from the device substrate, completing the opening of the device.

[0028] Furthermore, the surface of the sample press facing the cover plate is provided with a washable adhesive layer, and the sample press is bonded to the cover plate through the washable adhesive layer.

[0029] Furthermore, the sample press has multiple support pillars on the surface facing the water-washed adhesive layer.

[0030] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0031] a) The opening method for the cover plate sealing device provided by this invention uses a point-cutting method instead of the existing line-cutting method. The blade cutting is no longer along the sides of the two solder rings, but rather aligned with the intersection of the vertical line at the diagonal of the cover plate and the solder ring. This fully utilizes the integrity and integrated tension of the cover plate to complete the opening of the cover plate sealing device. This not only reduces the risk of porcelain chipping during the opening process, but also avoids introducing contamination or abnormal damage during opening, improving both the opening quality and speed.

[0032] (b) The opening method of the cover sealing device provided by this invention significantly improves the opening quality and speed because the accuracy and efficiency of aligning the blade with the intersection of the vertical line diagonally opposite the cover plate and the solder ring (point-to-point) are far greater than the accuracy and efficiency of aligning the blade with the side edge of the solder ring (line-to-line). Tests have shown that the opening method using the cover sealing device of this invention can increase the opening speed by 950%.

[0033] c) The opening method of the cover plate sealing device provided by the present invention cleverly avoids the problem of misalignment of the conventional process and eliminates the drawback of uneven force during line cutting. Instead, it breaks through and inserts at the intersection of the vertical line where the diagonal of the cover plate is located and the solder ring, making precise point cutting. It makes full use of the integrity and integrated tension of the cover plate to achieve high-quality, efficient and clean opening, which can greatly improve the opening quality and speed of DPA and failure analysis, and thus ensure the quality and schedule requirements of DPA and failure analysis.

[0034] d) The method for opening the cover sealing device provided by the present invention can increase the friction between the device to be opened and the sample stage by applying pressure to the device to be opened, thereby preventing the device to be opened from shifting and shaking during the opening process.

[0035] e) The opening method of the cover sealing device provided by the present invention has the opening point of the blade located on the side of the solder ring near the cover plate. In this way, the opening point can be as far away from the device substrate as possible. Even if porcelain chipping occurs during the opening process, the chipped part will usually only be in the solder ring and will basically not reach the device substrate, thereby effectively protecting the device substrate and avoiding damage to the device substrate.

[0036] f) The opening method of the cover sealing device provided by the present invention can significantly reduce the initial opening force of the blade compared with the prior art. This is because the line cutting method is improved to the point cutting method, and the blade and the solder ring are in point contact with a small contact area. Therefore, only a small initial opening force is needed to reach the pressure required for opening and cut the solder ring at the intersection. At the same time, the reduction of the initial opening force can further reduce the interaction force between the blade and the solder ring, thereby further protecting the device substrate and reducing the occurrence of porcelain chipping. In addition, the reduction of the initial opening force can also extend the service life of the blade.

[0037] g) The opening method of the cover plate sealing device provided by the present invention, for the cover plate gold-tin sealing device, during the opening process, through the rotation of the device to be opened and the step-by-step cutting of the opening blade, the contact between the blade and the solder ring is always point contact, which can significantly reduce the opening force required for opening, thereby reducing the occurrence of porcelain chipping of the device substrate during the opening process.

[0038] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0039] 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.

[0040] Figure 1 This is a schematic diagram showing the positional relationship between the blade and the cover plate in the opening method of the cover plate sealing device in the prior art;

[0041] Figure 2 A schematic diagram showing the positional relationship between the blade and the cover plate in the opening method of the cover plate sealing device provided by the present invention;

[0042] Figure 3 A schematic diagram of the structure of the cover sealing device in the opening method of the cover sealing device provided by the present invention;

[0043] Figure 4 The image shows the opening effect of the device substrate obtained by opening the cover sealing device according to the opening method of Embodiment 1 of the present invention.

[0044] Figure label:

[0045] 1-Device substrate; 2-Cover plate; 3-Solder ring; 4-Opening blade. Detailed Implementation

[0046] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of the present invention and, together with the embodiments of the present invention, serve to illustrate the principles of the present invention.

[0047] This invention provides a method for opening the sealing device of the cover plate 2, see [link to relevant documentation]. Figures 2 to 3 The sealing device 2 includes a device substrate 1 and a cover plate 2. The cover plate 2 and the device substrate 1 are sealed together by a solder ring 3. The opening method includes the following steps:

[0048] Step 1: Align the diagonal of the cover plate 2 with the blade of the opening blade 4;

[0049] Step 2: Adjust the height of the device to be opened so that the blade is aligned with the intersection of the vertical line of the diagonal of the cover plate 2 and the solder ring 3;

[0050] Step 3: Unseal the device to be unsealed to complete the unsealing of the cover plate 2 sealing device.

[0051] Compared with existing technologies, the opening method of the cover plate 2 sealing device provided by this invention adopts a point-cutting method instead of the existing line-cutting method. The blade cutting is no longer along the sides of the two solder rings 3, but is aligned with the intersection of the vertical line at the diagonal of the cover plate 2 and the solder ring 3. This fully utilizes the integrity and integral tension of the cover plate 2 to complete the opening of the cover plate 2 sealing device. In this way, not only can the risk of porcelain chipping of the cover plate 2 sealing device be reduced during the opening process, but also the introduction of contamination or abnormal damage during the opening process can be avoided, thus improving the opening quality and opening speed.

[0052] Specifically, because the accuracy and efficiency of aligning the blade with the intersection of the vertical line diagonally opposite the cover plate 2 and the solder ring 3 (point-to-point) is far greater than the accuracy and efficiency of aligning the blade with the side of the solder ring 3 (line-to-line), the opening quality and speed can be greatly improved. Tests have shown that the opening method using the cover plate 2 sealing device of this invention can increase the opening speed by 950%.

[0053] Meanwhile, the opening method of the cover plate 2 solder sealing device of the present invention cleverly avoids the problem of misalignment of the conventional process and eliminates the drawback of uneven force during wire cutting. Instead, it breaks through and inserts at the intersection of the vertical line where the diagonal of the cover plate 2 is located and the solder ring 3, making the point cutting precise. It makes full use of the integrity and integrated tension of the cover plate 2 to achieve high-quality, efficient and clean opening, which can greatly improve the opening quality and speed of DPA and failure analysis, and thus ensure the quality and schedule requirements of DPA and failure analysis.

[0054] The above-mentioned opening method can be performed using an opening machine, specifically including the following steps:

[0055] Step 1: Place the device to be opened on the sample stage of the opening machine and adjust the orientation of the device to be opened so that the diagonal of the cover plate 2 is perpendicular to the blade of the opening blade 4.

[0056] Step 2: Adjust the height of the sample stage of the opening machine (i.e., the central knob platform of the opening machine) so that the blade is aligned with the intersection of the vertical line where the diagonal of the cover plate 2 is located and the solder ring 3;

[0057] Step 3: Apply pressure to the blade so that it cuts into the intersection of the vertical line where the diagonal of the cover plate 2 is located and the solder ring 3, separating the cover plate 2 from the device substrate 1, thus completing the unpacking of the device to be unpacked.

[0058] In order to prevent the device to be opened from shaking and affecting the opening process, the following steps are included in step 3 above before applying pressure to the blade:

[0059] Apply pressure toward the sample stage to the device to be opened, so that the relative position of the device to be opened and the sample stage remains unchanged.

[0060] In this way, by applying pressure to the device to be opened, the friction between the device to be opened and the sample stage can be increased, thus preventing the device to be opened from shifting or shaking during the opening process.

[0061] It is worth noting that, considering the greater the possibility of damage to the device substrate 1 as the blade approaches it, the intersection of the vertical line containing the diagonal of the cover plate 2 and the solder ring 3 is the intersection of the vertical line containing the diagonal of the cover plate 2 and the side of the solder ring 3 closest to the cover plate 2. In other words, the opening of the blade is located on the side of the solder ring 3 closest to the cover plate 2. This ensures that the opening is as far away from the device substrate 1 as possible. Even if porcelain chipping occurs during the opening process, the chipped area will usually only be within the solder ring 3 and will generally not reach the device substrate 1, thus effectively protecting the device substrate 1 and preventing damage to it.

[0062] To further reduce the occurrence of porcelain chipping during the unpacking process of the device packaged in the cover plate 2, the initial unpacking force of the blade can be 0.8–2.5 N. Compared with the prior art, the unpacking method provided by this invention can significantly reduce the initial unpacking force of the blade. This is because by improving the line cutting method to a point cutting method, the blade and the solder ring 3 make point contact with each other, resulting in a small contact area. Therefore, only a small initial unpacking force is needed to achieve the pressure required for unpacking and cut the solder ring 3 at the intersection point. At the same time, the reduction in the initial unpacking force can further reduce the interaction force between the blade and the solder ring 3, thereby further protecting the device substrate 1 and reducing the occurrence of porcelain chipping. In addition, the reduction in the initial unpacking force can also extend the service life of the blade.

[0063] For example, the sealing device of the cover plate 2 can be a ceramic sealing device or a gold-tin sealing device. The ceramic sealing device refers to the solder ring 3 between the cover plate 2 and the device substrate 1 being made of ceramic material, while the gold-tin sealing device refers to the solder ring 3 between the cover plate 2 and the device substrate 1 being made of gold-tin material.

[0064] Because the ceramic sealing device and the gold-tin sealing device of cover plate 2 have different material properties, the applied initial opening force is also different. For example, if the sealing device of cover plate 2 is a ceramic sealing device, the initial opening force is 0.8 to 1.5 N (e.g., 0.8 N, 1.0 N, 1.3 N, 1.5 N, etc.). Correspondingly, if the sealing device of cover plate 2 is a gold-tin sealing device, the initial opening force is 2.0 to 2.5 N (e.g., 2.0 N, 2.1 N, 2.3 N, 2.5 N, etc.).

[0065] Specifically, for the ceramic sealing device of cover plate 2, due to the brittleness of ceramic material, when the blade cuts into the intersection of the vertical line where the diagonal of cover plate 2 is located and the solder ring 3, under the action of the integrity and tension of cover plate 2, cover plate 2 will basically separate from the device substrate 1 immediately, and the cutting depth of the blade does not need to be too large.

[0066] However, for the gold-tin sealing device of the cover plate 2, due to the high toughness of the gold-tin material, when the blade cuts into the intersection of the vertical line where the diagonal of the cover plate 2 is located and the solder ring 3, the cover plate 2 cannot immediately separate from the device substrate 1 due to the adhesive effect of the gold-tin material. In the prior art, it is necessary to manually apply pressure to the blade multiple times (for example, by striking the opening blade 4 with a hammer) to make it penetrate into the solder ring 3. During the penetration process, due to the poor accuracy of pressure and direction control, the chipping of the device substrate 1 still occurs. Therefore, the above step 3 includes the following steps:

[0067] Step 31: Apply pressure to the cutting edge so that the cutting edge cuts into the weld ring 3 at the intersection of the vertical line where the diagonal of the cover plate 2 is located.

[0068] Step 32: The device to be opened is rotated horizontally around the midpoint of the diagonal. The blade gradually penetrates into the solder ring 3 to rotate and open the device. The cover plate 2 separates from the device substrate 1, completing the opening of the device.

[0069] In this way, for the gold-tin sealing device of the cover plate 2, during the opening process, the rotation of the device to be opened and the step-by-step cutting of the opening blade 4 ensure that the contact between the blade and the solder ring 3 is always point contact, which can significantly reduce the opening force required for opening, thereby reducing the possibility of ceramic chipping of the device substrate 1 during the opening process.

[0070] In practical applications, a sample presser is usually used to apply pressure to the device to be opened to prevent it from shaking. However, since the surface of the cover plate 2 is relatively smooth, the sample presser and the cover plate 2 may loosen when the device to be opened is rotated. Therefore, a water-washable adhesive layer is provided on the surface of the sample press facing the cover plate 2. The sample presser is bonded to the cover plate 2 through the water-washable adhesive layer. In this way, when the device to be opened is rotated, the sample presser and the cover plate 2 are bonded through the water-washable adhesive layer, which can effectively improve the contact force between the two and basically avoid loosening between the sample presser and the cover plate 2.

[0071] It is worth noting that commercially available water-washed adhesive layers usually have a certain thickness. Applying pressure to the water-washed adhesive layer can easily lead to bias pressure, affecting the opening effect. Therefore, the sample press has multiple support columns on the surface facing the water-washed adhesive layer. Since the water-washed adhesive layer has a certain elasticity, when the sample press applies pressure to the device to be opened, the support columns can be appropriately inserted into the water-washed adhesive layer to compact it, improve the mechanical strength of the water-washed adhesive layer, and thus appropriately reduce the occurrence of bias pressure.

[0072] Example 1

[0073] In this embodiment, the device to be unsealed is a MAXIM MAX490 cover-sealed circuit. In this type of device, the cover plate and the device substrate are sealed with ceramic. Ceramic has high hardness and brittleness and is thin, so conventional unsealing methods can easily cause the ceramic to chip and be damaged. The unsealing method used in this embodiment includes the following steps:

[0074] Step a: Place the device to be opened on the sample stage of the BFL2100 ceramic encapsulation device unpacking machine;

[0075] Step b: Adjust the orientation of the device to be opened so that the diagonal of the device cover is perpendicular to the blades on both sides of the opening machine;

[0076] Step c: Rotate the handwheel of the opening machine to adjust the height of the platform of the center knob of the opening machine so that the blades on both sides of the opening machine are aligned with the two precise points where the vertical line of the diagonal line of the cover plate intersects with the solder ring;

[0077] Step d: Press down on the device, ensuring that the diagonal formed by the two aligned points is perpendicular to the blade.

[0078] Step e: Continue to rotate the handwheel of the unsealing machine to apply static pressure to the blade, so that the blade cuts in from two points. Due to the high brittleness of ceramic materials, when the blade cuts in from the intersection of the vertical line where the diagonal of the cover plate is located and the solder ring, under the action of the integrity and tension of the cover plate, the cover plate will basically separate from the device substrate immediately, completing the unsealing.

[0079] The unpacking effect of the device substrate obtained by the unpacking method of this embodiment is shown in the figure. Figure 4 .from Figure 4It can be seen that the internal structure of the device substrate is intact.

[0080] Example 2

[0081] In this embodiment, the device to be opened is a GED1763CS8 type gold-tin sealed cover device. In this type of device, the cover plate and the device substrate are sealed with a gold-tin alloy. The opening method used in this embodiment includes the following steps:

[0082] Step A: Place the device to be opened on the sample stage of the opening machine;

[0083] Step B: Adjust the orientation of the device to be opened so that the diagonal of the device cover is perpendicular to the blades on both sides of the opening machine;

[0084] Step C: Rotate the handwheel of the opening machine to adjust the height of the platform of the center knob of the opening machine so that the blades on both sides of the opening machine are aligned with the two precise points where the vertical line of the diagonal line of the cover plate intersects with the solder ring;

[0085] Step D: Press down on the device, ensuring that the diagonal formed by the two aligned points is perpendicular to the blade.

[0086] Step E: Continue to rotate the handwheel of the opening machine to apply static pressure to the blade, so that the blade cuts in from two points;

[0087] Step F: The device to be opened is rotated horizontally around the midpoint of the diagonal. The blade gradually penetrates into the solder ring to rotate and open the device. The cover plate separates from the device substrate, completing the opening of the device.

[0088] 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 method for opening a cover plate sealing device, the cover plate sealing device comprising a device substrate and a cover plate, wherein the cover plate and the device substrate are sealed together by a solder ring, characterized in that, The opening method includes the following steps: Step 1: Align the diagonal of the cover plate with the blade of the opening blade; Step 2: Adjust the height of the device to be opened so that the blade is aligned with the intersection of the vertical line where the cover plate is located and the solder ring; Step 3: Unseal the device to be opened to complete the unsealing of the cover sealing device; The cover plate sealing device is a cover plate gold-tin sealing device, and step 3 includes the following steps: Step 31: Apply pressure to the cutting edge so that it cuts into the solder ring at the intersection of the vertical line containing the diagonal of the cover plate. Step 32: Rotate the device to be opened horizontally around the midpoint of the diagonal. The blade gradually penetrates into the solder ring to rotate and open the device. The cover plate separates from the device substrate, completing the opening of the device. The contact between the cutting edge and the solder ring is always a point contact; A sample presser of an opening machine is used to apply pressure to the device to be opened. The surface of the sample presser facing the cover plate is provided with a water-washable adhesive layer. The sample presser is bonded to the cover plate through the water-washable adhesive layer. The sample press has multiple support columns on the surface facing the water-washed adhesive layer. When the sample press applies pressure to the device to be opened, the support columns are inserted into the water-washed adhesive layer to compact it.

2. The method for opening the cover sealing device according to claim 1, characterized in that, The opening method uses an opening machine to open the seal.

3. The method for opening the cover sealing device according to claim 1, characterized in that, Step 1 includes the following steps: placing the device to be opened on the sample stage of the opening machine, and adjusting the orientation of the device to be opened so that the diagonal of the cover plate is perpendicular to the blade of the opening blade. Step 2 includes the following steps: Adjust the height of the sample stage of the opening machine so that the blade is aligned with the intersection of the vertical line where the diagonal of the cover plate is located and the solder ring.

4. The method for opening the cover sealing device according to claim 1, characterized in that, Before applying pressure to the blade in step 31, the following steps are also included: Apply pressure toward the sample stage to the device to be opened, so that the relative position of the device to be opened and the sample stage remains unchanged.

5. The method for opening the cover sealing device according to any one of claims 1 to 4, characterized in that, The intersection of the vertical line containing the diagonal of the cover plate and the solder ring is the intersection of the vertical line containing the diagonal of the cover plate and the side of the solder ring closest to the cover plate.

6. The method for opening the cover sealing device according to any one of claims 1 to 4, characterized in that, The initial opening force of the blade is 0.8~2.5 N.

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