Ceramic substrate fragmentation method

Abstract

The invention discloses a ceramic substrate slicing method. The method comprises the steps that the depth of a scratch line is controlled to be within the interval range of 50%-60% of the thickness of a ceramic substrate; a row of blank circuit substrates are added on the original ceramic substrate; designing a ceramic substrate slicing tool based on the bending principle; in the slicing process, the whole plate is firstly and independently sliced, and then small slices are sliced, so that a final product is obtained. The depth of the new scratch line meets the production requirements of a production line and ensures the quality of the substrate; the novel ceramic substrate fragmentation tool is designed to assist product fragmentation, uncontrollability of manual fragmentation is replaced, devices on the surfaces of products are better protected, and product quality and production efficiency in fragmentation operation are improved. After the improved and optimized technology is used in production, the production efficiency is improved by 55% or above, and the product percent of pass is improved to 98% or above.

Description

Technical Field

[0001] The invention belongs to the field of integrated circuits, and in particular relates to a ceramic substrate slicing method. Background Art

[0002] With the strict implementation of national carbon emission standards, new energy vehicles and related industries are booming, the market scale is expanding, and demand is growing exponentially. Ceramic integrated circuits are widely used in the front-end thermal treatment system control of new energy vehicles (traditional vehicles), and there is a huge demand for commercial core chip control circuits in the market.

[0003] In the current general technology, the slicing process of ceramic integrated circuits has the problems of low efficiency, excessive slicing and lack of slicing, which affects the product performance and appearance.

[0004] During the production process, this series of products uses a 2mm thick ceramic substrate, with a large overall size (connected piece size: 112.2×96.8mm; single piece product size: 14.15×12.4×2mm), many connections, many components on the product surface, and a large variety of component sizes. It is not easy to separate the pieces during the production process, and the phenomenon of more ceramic and less ceramic after separation is more serious. In addition, during the separation process, it is easy to damage the components mounted on the front and back, thus affecting the circuit performance. Summary of the invention

[0005] The present invention provides a ceramic substrate slicing method, which is committed to solving the slicing process of a 2mm thick ceramic substrate through technical innovation and process improvement, so that the product process technology is optimized and improved, large-scale mass production is achieved, and product performance and appearance requirements are met.

[0006] A ceramic substrate slicing method, characterized in that the depth of the scratch line is controlled within the range of 50% to 60% of the thickness of the ceramic substrate; a row of blank circuit substrates is added to the original ceramic substrate; a ceramic substrate slicing tool using the bending principle is designed; and the slicing process adopts the method of first slicing the entire substrate into individual strips and then slicing into small pieces to obtain the final product.

[0007] Furthermore, the process of slitting the entire page individually is: taking the side where the blank substrate is located as the top, first remove the process edges of the bottom, left and right sides to reduce the force applied during slitting, retain the top blank substrate part, insert the end of the blank substrate into the groove of the fixed axis and the rotating axis, align the substrate scratch line with the bending part of the tooling, manually push the tooling rotating axis, and you can get a strip product; when inserting the blank substrate into the groove of the fixed axis and the rotating axis, it cannot be inserted from top to bottom, it should be inserted horizontally from left to right or from right to left, and the product must be kept stable after the rotating axis is rotated and bent to avoid large-scale shaking.

[0008] Furthermore, the process of dividing into small pieces is: insert the divided products into the grooves of the fixed axis and the rotating axis with the direction of the soldering pad as the bottom insertion direction, ensure that one end of the product is against the limit of the tooling, make the scratch line of the substrate and the bending part of the tooling align and overlap with each other, make sure that there is no alarm on the anti-foolproof photoelectric switch, step on the cylinder control switch, and the force cylinder pushes the rotating axis to rotate and bend downward to obtain the final product.

[0009] Furthermore, in the slicing step, the angle of rotation of the rotating shaft when it is bent downward is within the range of 5°±1°.

[0010] Furthermore, the ceramic substrate should be subjected to uniform force when being sliced ​​on the tooling.

[0011] Furthermore, when the rotating shaft rotates and bends downward, the assist spring will give it an upward thrust to assist the rotating shaft to rebound and return to the same horizontal position as the fixed shaft.

[0012] A ceramic substrate slicing tool, characterized in that it includes a fixed shaft and a rotating shaft, both of which are fixed on a tooling base, the fixed shaft is provided with a boss, the rotating shaft is provided with a groove adapted to the boss, the fixed shaft and the rotating shaft are engaged together using the boss and the groove; a fixed shaft groove is provided on the fixed shaft, and a rotating shaft groove is provided on the rotating shaft; when the fixed shaft groove and the rotating shaft groove are engaged, a herringbone notch is formed.

[0013] A force-applying cylinder, a power-assisting spring and an anti-foolproofing photoelectric switch are also fixed on the tooling base; a cylindrical contact device is installed on the top of the gas rod of the force-applying cylinder to provide soft contact between the device and the rotating shaft; one end of the power-assisting spring is fixed on the rotating shaft, and the other end is fixed on the spring base; the anti-foolproofing photoelectric switch is fixed on the rotating shaft through an anti-foolproofing photoelectric switch fixing seat; the direction of the rebound auxiliary force of the power-assisting spring forms an angle of 45° with the direction of the force applied by the gas rod.

[0014] The present invention has the following beneficial effects:

[0015] In the process optimization and improvement of product slicing, the first is to set a new scratch line depth to meet the production needs of the production line and ensure the quality of the substrate; the second is to re-plan the circuit layout of the substrate to improve the quality of the slicing products; the third is to design new tooling to assist product slicing, replacing the uncontrollability of manual slicing, better protecting the surface devices of the product, and improving the product quality and production efficiency in the slicing operation. After using the improved and optimized process in production, the production efficiency increased by more than 55%, and the product qualification rate increased to more than 98%. This process has been widely used in mass production, and both product quality and production efficiency have been improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a full-page product diagram;

[0017] Figure 2 It is a schematic diagram of striped products;

[0018] Figure 3 This is a schematic diagram of the front pad location;

[0019] Figure 4 This is a schematic diagram of the back pad location;

[0020] Figure 5 It is the overall schematic diagram of the slitting tooling;

[0021] Figure 6 It is a schematic diagram of striping operation;

[0022] Figure 7 It is the overall schematic diagram of the piece tooling;

[0023] Figure 8 It is a schematic diagram of the slice rotation combination;

[0024] Fig. 9 It is a schematic diagram of the operation of the slicing tooling;

[0025] Fig.10 is a schematic diagram of a fixed axis;

[0026] Fig.11 Schematic diagram of the rotating shaft;

[0027] Fig.12 is a schematic diagram of the groove of the rotating shaft;

[0028] Fig.13 It is a schematic diagram of the fixed shaft groove;

[0029] Fig.14 It is a schematic diagram of the force direction of the assist spring;

[0030] Explanation of the accompanying figures: 1- tooling base, 2- force cylinder, 3- rotating shaft, 4- fixed shaft, 5- rotating shaft groove, 6- fixed shaft groove, 7- assist spring, 8- spring base, 9- foolproof photoelectric switch, 10- foolproof photoelectric switch fixing seat, 11- cylindrical contact device. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings.

[0032] There are surface mount devices on the front and back of ceramic integrated circuits, and the number is large. The thickness of some devices is greater than the thickness of the substrate, so the devices on the raised parts are easily damaged during the slicing process. In addition, due to the physical properties of ceramic materials, there will be raised or sunken surface phenomena on the edges of the substrate of the product after slicing, that is, the phenomenon of more ceramic and less ceramic. The occurrence of this phenomenon will affect the adaptability and safety of the product itself, and cause certain electrical performance risks to the product.

[0033] After the product components are mounted and reflowed, product slicing mainly involves separating the connected substrate into small finished products. The next lead insertion process requires connecting the pads on the front and back of the product, which must be done in small pieces. Therefore, the slicing process is a link between the previous and the next, and the quality of slicing directly determines the product quality and production qualification rate.

[0034] In order to ensure the slicing quality of the product and improve the production qualification rate, the process upgrade and improvement are carried out on the three key points of product slicing, namely: 1. Substrate scratch line; 2. Substrate process layout; three-slicing method; the details are explained below.

[0035] 1. Substrate scratch line

[0036] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown in the figure, the scratch line of the product substrate is divided on the substrate according to the design requirements by laser technology. Its function is to facilitate the cracking of the substrate during slicing. Therefore, the depth of the scratch line determines the difficulty of slicing and the phenomenon of more porcelain and less porcelain. Taking the 2mm thick ceramic substrate of this product as an example, when the scratch line is shallow, the force required for slicing is greater. When the force is greater, the instantaneous force released when the substrate is separated is greater, and the phenomenon of porcelain collapse is more serious. Based on this principle, when the scratch line is 50%, that is, 1mm, the force required in the slicing process is greater, the product has more porcelain shortage and less porcelain phenomenon, and the product qualification rate is low; when the scratch line is 70%, that is, 1.4mm, the product is labor-saving during slicing, and the phenomenon of more porcelain and less porcelain is less, but the early circuit printing and solder paste printing will cause the substrate to crack, resulting in substrate waste. After multiple scratch line tests, the scratch line depth was finally controlled within the range of 50% to 60% of the ceramic substrate thickness to achieve the best balance, that is, circuit printing and solder paste printing would not cause the substrate to crack, and the working condition was intact, with less ceramic chipping and the best slicing condition.

[0037] 2. Substrate Process Layout

[0038] The process layout of the product mainly refers to the distribution of the circuit on the substrate. During the slicing process, there will be stress release at the moment the substrate cracks, and the release of force is the main cause of ceramic chipping. Therefore, in the process layout of the substrate, the corresponding circuit distribution will be designed according to the steps and directions of slicing to achieve the best state of slicing. In the full-plate state, the process edge of the substrate edge will be removed first in the slicing operation, which is more suitable for the slicing operation. However, after the process edge is removed, there is no force buffer during slicing, and the state of the strip is a long strip, resulting in the maximum force release at the end of the strip, which is most likely to cause ceramic chipping. If the process edge is not removed, there will be a certain force release area during the slicing process, but the force required for slicing will be greater. This is because the process edge is horizontally blocked in the direction of force transmission, that is, the slicing direction and the process edge are perpendicular to each other, which increases the difficulty of slicing.

[0039] After comprehensive consideration, the plan of increasing the area and removing the edges was finally adopted, which mainly added a row of blank circuit substrates, such as Figure 1 , Figure 2 As shown, the size of the overall substrate is increased, and a sufficient force release area is obtained during the slicing process to protect the integrity of the substrate; secondly, the process edge is removed first during the slicing process to reduce the force applied during slicing as much as possible, which also facilitates the cracking of the substrate. In addition, when slicing, the added blank circuit substrate can concentrate some of the excess and less porcelain phenomena well, without damaging the normally printed circuit substrate, and protecting the edge integrity of the substrate.

[0040] 3. Sharding

[0041] In order to reduce the phenomenon of too much or too little porcelain in production and meet product design requirements, manual slicing tests are first carried out according to traditional processes. However, there are many devices on the surface and there are clear requirements for the verticality of some devices. It is easy to touch the devices during manual slicing, which may cause damage or drop of the devices, thus affecting the electrical performance of the product.

[0042] In combination with product requirements and existing process methods, a ceramic substrate slicing tooling is designed using the bending principle, and the cylinder is used as the power to assist the operation during the slicing process. The primary design goal is to protect the integrity of the product substrate and devices, so in the early stage of design, corresponding grooves are designed according to the distribution of product devices and the thickness of the substrate to ensure that the devices will not touch the slicing tooling during the slicing process; secondly, the design is aimed at the phenomenon of more ceramics and less ceramics on the edge of the product. After the force analysis model demonstration, it is found that the phenomenon of more ceramics and less ceramics caused by uneven force is more obvious, so the force of the product on the tooling is as uniform as possible when slicing.

[0043] like Figure 5-Figure 12As shown, a ceramic substrate slicing tool comprises a fixed shaft 4 and a rotating shaft 3, both of which are fixed on a tooling base 1, the fixed shaft 4 is provided with a boss, the rotating shaft 3 is provided with a groove adapted to the boss, the fixed shaft and the rotating shaft are engaged with each other by means of the boss and the groove; a fixed shaft groove 6 is provided on the fixed shaft, and a rotating shaft groove 5 is provided on the rotating shaft; when the fixed shaft groove 6 and the rotating shaft groove 5 are engaged, a herringbone notch is formed.

[0044] A force-applying cylinder 2 and a spring base 8 are also fixed on the tooling base 1; a cylindrical contact device 11 is installed on the top of the gas rod of the force-applying cylinder to provide soft contact with the rotating shaft 3; one end of the assisting spring 7 is fixed on the rotating shaft 3, and the other end is fixed on the spring base 8; the anti-foolproof photoelectric switch 9 is fixed on the rotating shaft 3 through the anti-foolproof photoelectric switch fixing seat 10.

[0045] The overall slicing process is divided into full-page striping and small-piece cutting. Due to the different length and width of the products, in order to ensure the neat edges of the sliced ​​products, they are first sliced ​​independently and then into small pieces to obtain the final product.

[0046] like Figure 5 As shown, when stripping, the fixed axis groove 6 and the rotating axis groove 5 have the same size and are in mirror image position and direction.

[0047] like Figure 8 As shown, when divided into small pieces, the size of the fixed axis groove 6 is larger than the size of the rotating axis groove 5, and the position direction is a mirror image.

[0048] like Figure 6 As shown, the stripping process is as follows: adopt the fulcrum bending method, take the direction of the pad as the bottom insertion direction, take the side where the blank substrate is as the top, first remove the process edges of the bottom, left and right sides, retain the top process edge (i.e. the blank substrate part), insert the blank substrate end into the fixed axis groove 6 and the rotating axis groove 5, align the substrate scratch line with the bending part of the tooling, and use the bending principle to manually push the tooling rotating axis 3 to obtain a strip product. It should be noted that when inserting the fixed axis groove 6 and the rotating axis groove 5 in the direction of the pad end, it cannot be inserted from top to bottom. The protrusion of the special-shaped device on the back of the product is large, and it should be inserted horizontally from left to right or from right to left, and the product needs to be kept stable after rotation and bending to avoid large-scale shaking. In this way, the phenomenon of missing porcelain at both ends of a strip of product will be greatly reduced.

[0049] like Fig. 9As shown, the slicing process is as follows: using the pneumatic bending method, the slicing process is: insert the stripped product into the fixed shaft groove 6 and the rotating shaft groove 5 with the direction of the solder pad as the bottom insertion direction, ensure that one end of the product is against the tooling limit, so that the substrate scratch line and the tooling bending place are aligned and overlapped with each other, make sure that the anti-fool photoelectric switch 9 has no alarm, step on the cylinder control switch, and the force cylinder 2 pushes the rotating shaft 3 to rotate and bend downward to obtain the final product. When the rotating shaft 3 moves downward, the assist spring 7 will give it an upward thrust to assist the rotating shaft 3 to rebound and return to the same horizontal position as the fixed shaft 4. The direction of the assist spring rebound auxiliary force is at a 45° angle to the direction of the gas rod pushing force. As shown Fig.14 shown.

[0050] In the process of striping and slicing, the most important thing is to reduce the phenomenon of excess or insufficient ceramics in the products after slicing and ensure the dimensional integrity of the substrate.

[0051] During the stripping process, since the rotation point directly acts on the blank substrate, the substrate will be stressed and cracked as the angle changes during the rotation of the stripping axis. The force released instantly extends upward along with the blank substrate, and the force transmission gradually decreases as the distance increases. Therefore, the instantaneous force applied to the blank substrate is the largest and will not damage normal products. The rest of the force will be directly decomposed during the force transmission process due to the existence of the scratch line, and will not damage the substrate and devices. In this way, the phenomenon of less porcelain and edge collapse during stripping will be concentrated on the blank substrate, which is conducive to protecting the integrity of the product and the integrity of the device.

[0052] In the slicing step, the rotation angle of the tooling rotating shaft 3 when it is bent is crucial. If the rotation angle is small, the kinetic energy generated when the product splits cannot be dissipated in time, resulting in more obvious porcelain chipping; if the rotation angle is too large, the kinetic energy will be distributed at the edge of the substrate, causing serious porcelain deficiency in the product; therefore, the rotation angle of the rotating shaft is set within the range of 5°±1° according to the product thickness.

Claims

1. A ceramic substrate slicing method, characterized in that: The depth of the scratch line is controlled within the range of 50% to 60% of the thickness of the ceramic substrate; a row of blank circuit substrates is added to the original ceramic substrate; a ceramic substrate slicing tooling using the bending principle is designed; the slicing process is to first separate the entire substrate into strips and then into small pieces to obtain the final product.

2. The ceramic substrate slicing method according to claim 1, characterized in that: The process of separate stripping of the whole sheet is as follows: taking the side where the blank substrate is located as the top, first remove the process edges of the bottom, left and right sides to reduce the force applied during stripping, retain the top blank substrate part, insert the end of the blank substrate into the fixed shaft groove (6) and the rotating shaft groove (5), align the substrate scratch line with the bending part of the tooling, and manually push the tooling rotating shaft (3) to obtain a strip product; when the blank substrate is inserted into the fixed shaft groove (6) and the rotating shaft groove (5), it cannot be inserted from top to bottom, but should be inserted horizontally from left to right or from right to left, and after the rotating shaft (3) is rotated and bent, the product must be kept stable to avoid large-scale shaking.

3. The ceramic substrate slicing method according to claim 2, characterized in that: The process of dividing into small pieces is as follows: insert the divided products into the fixed shaft groove (6) and the rotating shaft groove (5) with the direction of the solder pad as the bottom insertion direction, ensure that one end of the product is against the tooling limit position, make the substrate scratch line and the tooling bending position aligned and overlapped with each other, make sure that the anti-fool photoelectric switch (9) has no alarm, step on the cylinder control switch, and the force cylinder (2) pushes the rotating shaft (3) to rotate and bend downward, so as to obtain the final product.

4. The ceramic substrate slicing method according to claim 3, characterized in that: In the slicing step, the angle of rotation of the rotating shaft (3) when it is bent downward is within the range of 5°±1°.

5. The ceramic substrate slicing method according to claim 4, characterized in that: The ceramic substrate should be subjected to uniform force when being sliced ​​on the tooling.

6. The ceramic substrate slicing method according to claim 5, characterized in that: When the rotating shaft (3) rotates and bends downward, the assisting spring (7) will give it an upward thrust to assist the rotating shaft (3) to rebound and return to the same horizontal position as the fixed shaft (4).

7. The ceramic substrate slicing tool of the ceramic substrate slicing method according to any one of claims 1 to 6, characterized in that: The fixed shaft (4) and the rotating shaft (3) are both fixed on a tooling base (1); the fixed shaft (4) is provided with a boss, the rotating shaft (3) is provided with a groove adapted to the boss, the fixed shaft (4) and the rotating shaft (3) are engaged with each other by means of the boss and the groove; a fixed shaft groove (6) is provided on the fixed shaft, and a rotating shaft groove (5) is provided on the rotating shaft; when the fixed shaft groove (6) and the rotating shaft groove (5) are engaged with each other, a herringbone notch is formed.

8. The ceramic substrate slicing tool as claimed in claim 7, characterized in that: A force-applying cylinder (2), a power-assisting spring (7) and an anti-fool-proof photoelectric switch (9) are also fixed on the tooling base (1); a cylindrical contact device (11) is installed on the top of the gas rod of the force-applying cylinder (2) to provide soft contact between the cylindrical contact device and the rotating shaft (3); one end of the power-assisting spring (7) is fixed on the rotating shaft (3), and the other end is fixed on the spring base (8); the anti-fool-proof photoelectric switch (9) is fixed on the rotating shaft (3) via an anti-fool-proof photoelectric switch fixing seat (10); and the direction of the rebound auxiliary force of the power-assisting spring (7) forms an angle of 45° with the direction of the force applied by the gas rod.

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