A circuit board and a method for preparing the same

Abstract

The present application discloses a circuit board and a preparation method thereof, the preparation method comprising: providing a first substrate and a second substrate; setting a first groove on the first substrate and placing an adhesive member bonded to the groove wall in the first groove, the first groove extending to at least one side of the first substrate, the adhesive member disappears when it is at a first temperature; stacking a second substrate on the side of the first substrate where the adhesive member is set, pressing the first substrate and the second substrate to form an integral structure; setting a second groove with a width smaller than the first groove and exposing the first groove at the position of the second substrate corresponding to the adhesive member, the second groove extending to at least one side of the second substrate, the side of the first substrate connected to the first groove and the side of the second substrate connected to the second groove are adjacently arranged; removing the adhesive member after the overall structure is at the first temperature. The preparation method of the present application can process a circuit board with an inverted T-shaped step groove, which is convenient for realizing the lateral insertion of components, thereby improving the convenience of installation.

Description

Technical Field

[0001] The present application relates to the field of circuit boards, and in particular to a circuit board and a method for preparing the same. Background Art

[0002] In recent years, with the continuous popularization and application of electronic information and communication technology, the hardware equipment supporting information technology has experienced rapid development, and the processing technology requirements for the integrated circuit substrate part of the hardware equipment have become increasingly higher. In order to be able to more conveniently install components on the integrated circuit substrate, traditional integrated circuit substrates are provided with step grooves designed to match the components.

[0003] The inventors of this application have discovered that the step grooves on traditional integrated circuit carriers are often processed into rectangular or T-shaped shapes. When installing components, solder paste needs to be printed on the bottom of the groove and then bonded after reflow heating. This requires a relatively high thickness of the solder paste and there is a risk of it falling off. Summary of the invention

[0004] The main technical problem solved by the present application is to provide a circuit board and a preparation method thereof, which can process a circuit board with an inverted T-shaped step groove, facilitate the lateral insertion of components, and thus improve the convenience of installation.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a method for preparing a circuit board, the preparation method comprising: providing a first substrate and a second substrate, setting a first groove on the first substrate and placing an adhesive member bonded to the groove wall in the first groove, the first groove extending to at least one side of the first substrate, and the adhesive member loses its viscosity when it is at a first temperature; stacking the second substrate on the side of the first substrate where the adhesive member is set, and then pressing the first substrate and the second substrate to form an integral structure; setting a second groove with a width smaller than the first groove and exposing the first groove at a position of the second substrate corresponding to the adhesive member, the second groove extending to at least one side of the second substrate, and the side of the first substrate connected to the first groove and the side of the second substrate connected to the second groove are adjacent to each other; removing the adhesive member after the integral structure is at the first temperature.

[0006] In order to solve the above technical problems, another technical solution adopted in the present application is: providing a circuit board, the circuit board comprising a first substrate and a second substrate which are stacked, the first substrate being provided with a first groove, the second substrate being provided with a second groove exposing the first groove, the width of the second groove being smaller than the width of the first groove, the first groove extending to at least one side of the first substrate, the second groove extending to at least one side of the second substrate, the side of the first substrate connected to the first groove and the side of the second substrate connected to the second groove being adjacent to each other.

[0007] The beneficial effect of the present application is: the preparation method of the circuit board of the present application is to first prepare a first groove on the first substrate, place a special adhesive part whose viscosity disappears when it is at a first temperature in the first groove to replace the gasket in the traditional controlled depth processing method, and then press the first substrate and the second substrate together, and prepare a second groove with a width smaller than the first groove and exposing the first groove at the corresponding adhesive part of the second substrate, and take out the adhesive part whose viscosity disappears after rising to a certain temperature, and finally form an inverted T-shaped step groove, so that components can be horizontally inserted into the inverted T-shaped step groove, thereby improving the convenience of installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0009] in:

[0010] Figure 1 It is a schematic diagram of a process of an embodiment of a method for preparing a circuit board of the present application;

[0011] Figure 2 It corresponds to Figure 1 Partial preparation process diagram of the preparation method;

[0012] Figure 3 In one embodiment Figure 2 The subsequent preparation process diagram;

[0013] Figure 4 It is a structural schematic diagram of an implementation method of mounting components on a circuit board of the present application;

[0014] Figure 5 It is a structural schematic diagram of an implementation scheme of a circuit board of the present application. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0016] See also Figure 1 , Figure 1 is a schematic diagram of a process for preparing a circuit board according to an embodiment of the present invention, Figure 2 and Figure 3 , the preparation method of the circuit board comprises:

[0017] S110 : providing a first substrate 1100 and a second substrate 1200 .

[0018] The first substrate 1100 and the second substrate 1200 are basic materials for manufacturing circuit boards and can play a supporting role. There is no limitation on their specific structures.

[0019] S120: a first groove 1410 is provided on the first substrate 1100 and an adhesive member 1300 bonded to the groove wall is placed in the first groove 1410, the first groove 1410 extends to at least one side of the first substrate 1100, and the adhesive member 1300 loses its viscosity when at a first temperature.

[0020] The first groove 1410 may be processed by laser cutting, depth controlled grooving with a milling cutter, high-pressure water jet grooving, etc., which are not limited here.

[0021] The first groove 1410 extends to at least one side of the first substrate 1100. Specifically, the first groove 1410 extends to one side of the first substrate 1100, or the first groove 1410 extends to two opposite sides of the first substrate 1100. The purpose of extending the first groove 1410 to the side of the first substrate 1100 is to facilitate the subsequent insertion of components from the side of the circuit board.

[0022] The adhesive member 1300 is adhesive at room temperature, and its adhesiveness completely disappears when the temperature rises or drops to a certain level. In this embodiment, the adhesive member 1300 is first arranged in the first groove 1410, and then the adhesive member 1300 is taken out from the first groove 1410 when the temperature is at the first temperature.

[0023] S130 : stacking the second substrate 1200 on the side of the first substrate 1100 where the adhesive member 1300 is disposed, and then pressing the first substrate 1100 and the second substrate 1200 together to form an integral structure.

[0024] S140: A second groove 1420 having a width smaller than the first groove 1410 and exposing the first groove 1410 is arranged at the second substrate 1200 corresponding to the adhesive member 1300, the second groove 1420 extends to at least one side of the second substrate 1200, and the side of the first substrate 1100 connected to the first groove 1410 and the side of the second substrate 1200 connected to the second groove 1420 are arranged adjacent to each other.

[0025] The first groove 1410 is connected to the second groove 1420 to form an inverted T-shaped step groove.

[0026] The processing method of the second groove 1420 is the same as the processing method of the first groove 1410 , and please refer to the corresponding content above for details.

[0027] Similar to the first groove 1410 , the second groove 1420 also needs to extend to one side edge or two opposite sides of the second substrate 1200 .

[0028] At the same time, the purpose of adjacently arranging the side of the first substrate 1100 communicating with the first groove 1410 and the side of the second substrate 1200 communicating with the second groove 1420 is to facilitate the subsequent horizontal insertion of components in the step groove from the side of the circuit board.

[0029] S150: After the entire structure is at a first temperature, the adhesive member 1300 is removed.

[0030] After the adhesive member 1300 is removed, the circuit board 1000 is obtained.

[0031] Usually, the above steps S110 to S140 are performed at room temperature, and then after the overall structure is formed, the temperature is increased or decreased to a first temperature to make the viscosity of the adhesive member 1300 disappear, and finally the adhesive member 1300 is removed.

[0032] The means for removing the adhesive member 1300 may be physical, chemical or a combination of these means, which are not limited here.

[0033] In the prior art, during the process of machining step grooves, gaskets are generally placed in the grooves to block glue. This solution has the following defects: the gaskets are not sticky and cannot effectively fit with the bottom of the groove, resulting in poor glue blocking effect. In addition, in order to be able to remove the gaskets after the machining is completed, the shape of the gaskets is generally I-shaped or T-shaped, and such gaskets cannot be used to machine inverted T-shaped grooves.

[0034] In the present embodiment, an adhesive member 1300 is used instead of a gasket. On the one hand, the adhesive member 1300 can effectively fit with the bottom of the groove and has a good glue-blocking effect. On the other hand, since the viscosity of the adhesive member 1300 completely disappears at the first temperature, it can be removed, thereby ensuring the formation of an inverted T-shaped step groove, which can facilitate the subsequent components to be laterally inserted into the inverted T-shaped step groove, thereby improving the convenience of installation.

[0035] Continue reading Figure 2 The first substrate 1100 includes a first core board 1010 and an adhesive layer 1140 which are stacked, and the second substrate 1200 includes a second core board 1020 ; the step of setting a first groove 1410 on the first substrate 1100 includes: setting the first groove 1410 on the adhesive layer 1140 .

[0036] Specifically, in this embodiment, by configuring the first substrate 1100 to include an adhesive layer 1140 , it can be ensured that after being pressed together, the first substrate 1100 and the second substrate 1200 form an integral structure.

[0037] In this embodiment, the adhesive layer 1140 is a prepreg, which is also called a PP sheet. It is one of the main materials in the production of multilayer boards and is mainly composed of resin and reinforcing materials. It softens under heating and pressure and reacts and solidifies after cooling. In other embodiments, the adhesive layer 1140 may also include other materials with adhesive properties, which are not limited here.

[0038] Continue reading Figure 2 and Figure 3 In this embodiment, the first core board 1010 includes a first conductive layer 1110, a first base layer 1130 and a second conductive layer 1120 stacked in sequence, the second core board 1020 includes a third conductive layer 1210, a second base layer 1230 and a fourth conductive layer 1220 stacked in sequence, and the adhesive layer 1140 is arranged adjacent to the second conductive layer 1120, wherein the step of setting a first groove 1410 on the adhesive layer 1140 includes: making a groove on the adhesive layer 1140 until the bottom of the groove reaches the surface of the second conductive layer 1120, thereby forming the first groove 1410.

[0039] Specifically, the purpose of setting the bottom of the first groove 1410 to reach the surface of the second conductive layer 1120 is to enable the components subsequently placed in the first groove 1410 to directly contact the second conductive layer 1120, and to use the thermal conductivity of the second conductive layer 1120 to improve the heat dissipation speed of the components.

[0040] Of course, in other embodiments, the first groove 1410 may not reach the surface of the second conductive layer 1120 . For example, the first groove 1410 may only reach half of the thickness of the adhesive layer 1140 . This is not specifically limited here.

[0041] In this embodiment, the step of setting a second groove 1420 with a width smaller than the first groove 1410 and exposing the first groove 1410 at the adhesive part 1300 of the second substrate 1200 includes: calculating the sum of the thickness of the second core board 1020 and the thickness of the adhesive part 1300, and defining the sum as a first value; calculating the difference between the first value and the preset value, and defining the difference as a second value; and grooved at the adhesive part 1300 of the second core board 1020 to a groove depth of the second value, thereby forming the second groove 1420.

[0042] By setting a preset value, the depth of the groove can be controlled during the process of setting the second groove 1420 , so that the groove is only opened to the adhesive member 1300 without touching the second conductive layer 1120 , thereby avoiding damage to the second conductive layer 1120 .

[0043] For ease of understanding, an example is given here. In one application scenario, the preset value is Z, the thickness of the second core board 1020 is X, and the thickness of the adhesive member 1300 is Y. Then the second value is X+YZ, that is, the groove depth when setting the second groove 1420 is X+YZ.

[0044] Of course, in other embodiments, during the process of setting the second groove 1420 , the depth of the second groove 1420 can also be controlled to be the thickness of the second core board 1020 , that is, a groove is opened at the second core board 1020 corresponding to the adhesive 1300 until the groove depth is the thickness of the second core board 1020 .

[0045] Continue reading Figure 2 and Figure 3 The step of stacking the second substrate 1200 on the side of the first substrate 1100 where the adhesive part 1300 is provided includes: placing the second core board 1020 on the side of the adhesive layer 1140 away from the first core board 1010, and arranging the third conductive layer 1210 adjacent to the adhesive layer 1140; the step of arranging a second groove 1420 having a width smaller than the first groove 1410 and exposing the first groove 1410 at the adhesive part 1300 of the second substrate 1200 includes: arranging a first sub-groove 1421 at the fourth conductive layer 1220 corresponding to the adhesive part 1300 to expose the second base layer 1230; and arranging a second sub-groove 1422 at the exposed second base layer 1230 to expose the first groove 1410, wherein the width of the first sub-groove 1421 is greater than the width of the second sub-groove 1422, and the width of the second sub-groove 1422 is less than the width of the first groove 1410.

[0046] The purpose of setting the first sub-groove 1421 and the second sub-groove 1422 in the above steps and the first sub-groove 1421 having a width greater than the second sub-groove 1422 is to perform step-by-step groove cutting on the fourth conductive layer 1220 and the second base layer 1230. The first sub-groove 1421 is firstly used to determine the general size and contour range of the required second groove 1420, and then the second sub-groove 1422 is cut on the basis of the groove contour of the first sub-groove 1421 to determine the specific size of the required second groove 1420, thereby improving the precision and quality of the processed groove. In addition, setting the width of the second sub-groove 1422 smaller than the width of the first groove 1410 can make the processed groove 1400 present an inverted T shape as a whole.

[0047] Of course, in other implementations, the fourth conductive layer 1220 may be directly grooved to the second depth value instead of being grooved in steps, which is not specifically limited here.

[0048] In this embodiment, the adhesive member 1300 is a multi-layered special tape, and its viscosity disappears at a first temperature. For example, if the viscosity of the special tape completely disappears at a temperature of 180°C, the first temperature can be set to 180°C; if the viscosity of the special tape completely disappears at a temperature of -180°C, the first temperature can be set to -180°C.

[0049] In this embodiment, before placing the adhesive member 1300 bonded to the groove wall in the first groove 1410, it also includes: determining the number of sheets of multi-layer special tape; wherein the step of determining the number of sheets of multi-layer special tape includes: obtaining the depth of the first groove 1410 and the thickness of a single layer of special tape; calculating the quotient and remainder of the depth of the first groove 1410 divided by the thickness of the single layer of special tape; if the remainder is greater than a third value, determining the number of sheets of the special tape is the quotient plus one; if the remainder is less than the third value, determining the number of sheets of the special tape is the quotient.

[0050] For ease of understanding, an example is given here. In an application scenario, the thickness of a single layer of special tape is 35um, the depth of the first groove 1410 is 150um, the calculated quotient is 4, and the remainder is 10, where the pre-set third value is 15. Because the remainder 10 is less than 15, it can be determined that the number of sheets of special tape is 4.

[0051] The third numerical value here can be set according to actual conditions. The setting principle is to allow the multi-layer special tape to fill the first groove 1410 as much as possible without exceeding it excessively. No specific limitation is made here.

[0052] Combination Figure 4 In this embodiment, the method further includes:

[0053] A component 1500 is provided. The component 1500 includes a first portion 1501 and a second portion 1502 connected to each other. The width of the first portion 1501 is equal to the width of the first groove 1410 , and the width of the second portion 1502 is equal to the width of the second groove 1420 .

[0054] The component 1500 is mounted such that the first portion 1501 is located in the first groove 1410 and the second portion 1502 is located in the second groove 1420 .

[0055] The component 1500 may be a bare chip or a packaged chip, such as Figure 4 As shown, the component 1500 is a bare chip inserted horizontally in the inverted T-shaped slot and connected to the fourth conductive layer 1220 through a metal wire 1510, so that the chip is connected to the circuit board 1000. If the component 1500 is a packaged chip, it can be directly inserted horizontally on the circuit board 1000 without the need for metal wire connection.

[0056] See also Figure 5 , Figure 5 It is a structural schematic diagram of an embodiment of a circuit board of the present application, wherein the circuit board 2000 includes a first substrate 2100 and a second substrate 2200 which are stacked, the first substrate 2100 is provided with a first groove 2310, the second substrate 2200 is provided with a second groove 2320 which exposes the first groove 2310, the width of the second groove 2320 is smaller than the width of the first groove 2310, the first groove 2310 extends to at least one side of the first substrate 2100, the second groove 2320 extends to at least one side of the second substrate 2200, and the side of the first substrate 2100 connected to the first groove 2310 and the side of the second substrate 2200 connected to the second groove 2320 are adjacently arranged.

[0057] The circuit board 2000 in this embodiment is prepared by any preparation method. The detailed structure and method can be found in the above embodiments and will not be described again here.

[0058] In summary, the inventive method of the present application prepares a circuit board with an inverted T-shaped step groove, and provides a component that is also in an inverted T shape. The inverted T-shaped component is fixed by the transversely concave groove of the inverted T-shaped step groove, thereby realizing the transverse insertion of components on the circuit board and improving the convenience and reliability of installation.

[0059] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a circuit board, characterized in that: include: Providing a first substrate and a second substrate; A first groove is provided on the first substrate and an adhesive member bonded to the groove wall is placed in the first groove, the first groove extends to at least one side of the first substrate, and the adhesive member loses its viscosity when it is at a first temperature; The second substrate is stacked on the side of the first substrate where the adhesive member is disposed, and then the first substrate and the second substrate are pressed together to form an integral structure; A second groove having a width smaller than the first groove and exposing the first groove is provided at a position of the second substrate corresponding to the adhesive member, the second groove extends to at least one side of the second substrate, and a side of the first substrate communicating with the first groove and a side of the second substrate communicating with the second groove are adjacently provided; The adhesive is removed after the integrated structure is exposed to the first temperature.

2. The preparation method according to claim 1, characterized in that: The first substrate includes a first core plate and an adhesive layer which are stacked, and the second substrate includes a second core plate; The step of providing a first groove on the first substrate includes: The first groove is provided on the adhesive layer.

3. The preparation method according to claim 2, characterized in that: The adhesive layer includes a prepreg.

4. The preparation method according to claim 2, characterized in that: The first core plate includes a first conductive layer, a first base layer, and a second conductive layer stacked in sequence, the second core plate includes a third conductive layer, a second base layer, and a fourth conductive layer stacked in sequence, the adhesive layer is disposed adjacent to the second conductive layer, wherein the step of providing the first groove on the adhesive layer includes: A groove is made on the adhesive layer until the bottom of the groove reaches the surface of the second conductive layer, thereby forming the first groove.

5. The preparation method according to claim 4, characterized in that: The step of providing a second groove having a width smaller than the first groove and exposing the first groove on the second substrate corresponding to the adhesive member comprises: Calculating the sum of the thickness of the second core plate and the thickness of the adhesive member, and defining the sum as a first value; Calculating a difference between the first value and a preset value, and defining the difference as a second value; A groove is formed in the second core plate at a position corresponding to the adhesive member until the groove depth reaches the second value, thereby forming the second groove.

6. The preparation method according to claim 4, characterized in that: The step of stacking the second substrate on the side of the first substrate where the adhesive member is disposed comprises: Placing the second core board on the side of the adhesive layer away from the first core board, and arranging the third conductive layer adjacent to the adhesive layer; The step of providing a second groove having a width smaller than the first groove and exposing the first groove on the second substrate corresponding to the adhesive member comprises: A first sub-groove is provided at a position of the fourth conductive layer corresponding to the adhesive member to expose the second base layer; A second sub-groove is provided at the exposed second base layer to expose the first groove, wherein a width of the first sub-groove is greater than a width of the second sub-groove, and a width of the second sub-groove is less than a width of the first groove.

7. The preparation method according to claim 1, characterized in that: The adhesive member is a multi-layer special adhesive tape that is stacked.

8. The preparation method according to claim 7, characterized in that: Before placing the adhesive member bonded to the groove wall in the first groove, the method further includes: determining the number of the multi-layer special adhesive tape; The step of determining the number of sheets of the multi-layer special adhesive tape comprises: Obtaining the depth of the first groove and the thickness of a single layer of the special adhesive tape; Calculating the quotient and remainder of the depth of the first groove divided by the thickness of a single layer of the special adhesive tape; If the remainder is greater than a third value, the number of sheets of the special tape is determined to be the quotient plus one; If the remainder is smaller than the third value, the number of sheets of the special tape is determined to be the quotient.

9. The preparation method according to claim 1, characterized in that: The method further comprises: A component is provided, the component comprising a first part and a second part connected to each other, the width of the first part is equal to the width of the first groove, and the width of the second part is equal to the width of the second groove; The component is mounted so that the first portion is located in the first groove and the second portion is located in the second groove.

10. A circuit board prepared by the preparation method according to any one of claims 1 to 9; characterized in that: It includes a first substrate and a second substrate which are stacked, wherein the first substrate is provided with a first groove, and the second substrate is provided with a second groove which exposes the first groove, the width of the second groove is smaller than the width of the first groove, the first groove extends to at least one side of the first substrate, the second groove extends to at least one side of the second substrate, and the side of the first substrate connected to the first groove and the side of the second substrate connected to the second groove are adjacently arranged.

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