Circuit board and display device having the same

Abstract

The present invention discloses a circuit board and a display device having the circuit board. The circuit board comprises: a circuit board body, one side of the circuit board body is a part mounting surface, the other side of the circuit board body is a base surface, a heat dissipation pad is provided on the part mounting surface, a heat dissipation hole is opened on the circuit board body from the base surface to the heat dissipation pad, a bottom solder mask is provided on the base surface, the bottom solder mask flows into the heat dissipation hole so that the heat dissipation hole is formed into a semi-plug hole, a reinforced solder mask is provided outside the bottom solder mask, and the reinforced solder mask covers the semi-plug hole. According to the circuit board of the present invention, by providing a reinforced solder mask, the semi-plug hole of the circuit board is well sealed, and the tin at the part can be prevented from leaking from the semi-plug hole from the part mounting surface to the base surface, which is beneficial to improving the mounting accuracy and yield rate of the circuit board.

Description

Technical Field

[0001] The present invention relates to the field of electrical technology, and in particular to a circuit board and a display device having the circuit board. Background Art

[0002] In the related art, on a circuit board, for parts with a heat sink pad in the center, it is necessary to drill a semi-plug hole when designing the circuit board to dissipate the heat from the heat sink pad and achieve a better heat dissipation effect. However, due to the different plugging rate control capabilities of different factories, there is a risk that the solder will easily flow into the semi-plug hole when it melts and overflow from the other side of the circuit board, causing poor tinning of the heat sink pad and uneven solder distribution, thereby reducing the mounting accuracy. Summary of the invention

[0003] The present invention aims to solve at least one of the above-mentioned technical problems in the prior art to a certain extent. To this end, the present invention provides a circuit board that can better seal the semi-plugged via.

[0004] The invention also provides a display device having the circuit board.

[0005] The circuit board according to the embodiment of the present invention includes: a circuit board body, one side of the circuit board body is a part mounting surface, the other side of the circuit board body is a base surface, a heat dissipation pad is arranged on the part mounting surface, a heat dissipation hole is opened on the circuit board body and passes through from the base surface to the heat dissipation pad, a bottom solder mask is arranged on the base surface, the bottom solder mask flows into the heat dissipation hole to form the heat dissipation hole into a semi-plugged hole, a reinforced solder mask is arranged outside the bottom solder mask, and the reinforced solder mask covers the semi-plugged hole.

[0006] According to the circuit board of the embodiment of the present invention, by providing a reinforced solder mask, the semi-plugged holes of the circuit board are well sealed and tin leakage does not occur, which is beneficial to improving the mounting accuracy and yield rate of the circuit board.

[0007] According to some embodiments of the present invention, a half-plugged hole is provided at the half-plugged hole, and the half-plugged hole conductive portion includes a conductive portion body located in the half-plugged hole and a bottom pad located on the substrate surface, the conductive portion body is electrically connected to the heat dissipation pad, the bottom pad is electrically connected to the conductive portion body, the bottom solder mask covers the bottom pad, and the reinforced solder mask covers the bottom pad from the outside of the bottom solder mask.

[0008] According to some embodiments of the present invention, the semi-plugged via further includes a top-layer pad located on the component mounting surface, the via body is electrically connected to the top-layer pad, and the top-layer pad is electrically connected to the heat dissipation pad.

[0009] According to some embodiments of the present invention, the thickness of the reinforced solder mask is 0.3 mil-0.7 mil.

[0010] According to some embodiments of the present invention, the number of the half-plugged vias corresponding to a single heat dissipation pad is multiple.

[0011] According to some embodiments of the present invention, the number of the reinforced solder mask and the half-plugged vias are consistent and their positions correspond one to one.

[0012] According to some embodiments of the present invention, a top solder mask layer is provided on the component mounting surface, and the top solder mask layer avoids the heat dissipation pad.

[0013] According to some embodiments of the present invention, the thickness of the top solder mask layer and the bottom solder mask layer is 0.3 mil-0.7 mil.

[0014] According to some embodiments of the present invention, the top solder resist layer and the bottom solder resist layer are green oil layers, and the reinforced solder resist layer is a white oil layer.

[0015] A display device according to another embodiment of the present invention includes the above-mentioned circuit board.

[0016] According to the display device of the embodiment of the present invention, the semi-plugged vias of the circuit board are well sealed and tin leakage does not occur, so that the mounting accuracy of the circuit board is high and the yield rate is high.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional schematic diagram of a circuit board;

[0019] Figure 2 It is a top view of the circuit board;

[0020] Figure 3 This is a bottom view of the circuit board;

[0021] Figure 4 It is an enlarged schematic diagram of the semi-plugged via, bottom pad, and reinforced solder mask.

[0022] Reference numerals:

[0023] Circuit board body 1, part mounting surface 11, base surface 12, semi-plugged hole 13, heat dissipation pad 2, bottom solder mask 3, reinforced solder mask 4, top solder mask 5, semi-plugged hole conductive part 6, conductive part body 61, bottom pad 62, top pad 63, and ordinary pad 7. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0025] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, in the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Combine the following Figure 1-Figure 4 A circuit board and a display device according to embodiments of the present invention are described in detail.

[0028] Reference Figure 1-Figure 2 As shown, a circuit board (also called a PCB board) according to an embodiment of the present invention may include a circuit board body 1, one side of the circuit board body 1 is a component mounting surface 11, and the other side of the circuit board body 1 is a base surface 12, for example, Figure 1 In the embodiment, the top side of the circuit board body 1 is the component mounting surface 11, and the bottom side of the circuit board body 1 is the base surface 12. The component is suitable for being mounted on the component mounting surface 11, and the component may be a chip, a resistor, etc.

[0029] A heat dissipation pad 2 is provided on the component mounting surface 11, and the heat dissipation pad 2 corresponds to the center of the component. A plurality of common pads 7 can be provided around the heat dissipation pad 2, and the pins on both sides of the component can be welded and fixed to the common pads 7, and the center of the component can be welded and fixed to the heat dissipation pad 2.

[0030] The circuit board body 1 is provided with a heat dissipation hole that passes through the base surface 12 to the heat dissipation pad 2. In this way, part of the heat in the center of the component can be dissipated through the heat dissipation hole, and the other part of the heat can be first transferred to the heat dissipation pad 2 and then dissipated from the heat dissipation hole through the heat dissipation pad 2, thereby effectively preventing the component from being damaged due to excessive temperature. Figure 1 As shown, the heat dissipation hole passes through the circuit board body 1 and the heat dissipation pad 2 in the up and down directions.

[0031] Reference Figure 1 , Figure 3 As shown, a bottom solder mask 3 is provided on the base surface 12, and the bottom solder mask 3 is a non-conductive material. The bottom solder mask 3 flows into the heat dissipation hole to form the heat dissipation hole into a semi-plug hole 13. The bottom solder mask 3 in the heat dissipation hole has the function of blocking the heat dissipation hole, so that when the parts are soldered on the part mounting surface 11, the solder paste will not flow from the heat dissipation hole to the base surface 12. A reinforcing solder mask 4 is provided outside the bottom solder mask 3, and the reinforcing solder mask 4 covers the semi-plug hole 13. In other words, the edge of the reinforcing solder mask 4 extends outwardly beyond the edge of the semi-plug hole 13, so that the reinforcing solder mask 4 can completely cover the semi-plug hole 13 from the outside of the bottom solder mask 3, so that the semi-plug hole 13 is well sealed and there will be no tin leakage.

[0032] According to the circuit board of the embodiment of the present invention, by providing a reinforced solder mask 4, the semi-plug hole 13 of the circuit board is well sealed, which can prevent the tin at the part from leaking from the semi-plug hole 13 from the part mounting surface 11 to the base surface 12, which is beneficial to improving the mounting accuracy and yield rate of the circuit board.

[0033] In some embodiments of the present invention, reference Figure 1-Figure 4 As shown, a semi-plug hole 13 is provided with a semi-plug hole conductive part 6, and the semi-plug hole conductive part 6 may include a conductive part body 61 and a bottom pad 62. The conductive part body 61 is located in the semi-plug hole 13, and the bottom pad 62 is located on the base surface 12. The conductive part body 61 is electrically connected to the heat dissipation pad 2, and the bottom pad 62 is electrically connected to the conductive part body 61. The bottom solder mask 3 covers the bottom pad 62. In this way, a connected circuit can be formed between the part mounting surface 11 and the base surface 12.

[0034] The reinforced solder resist layer 4 covers the bottom pad 62 from the outside of the bottom solder resist layer 3. In other words, the reinforced solder resist layer 4 is located on the side of the bottom solder resist layer 3 that is away from the circuit board body 1, and the edge of the reinforced solder resist layer 4 extends outward beyond the edge of the bottom pad 62. In this way, the reinforced solder resist layer 4 can completely cover the bottom pad 62 from the outside of the bottom solder resist layer 3, and can also completely cover the semi-plug hole 13, and tin is not easy to leak from the semi-plug hole 13.

[0035] exist Figure 1 , Figure 3-Figure 4In the embodiment shown, the semi-plug hole 13, the reinforced solder mask 4, and the bottom pad 62 are all circular, and the diameter of the reinforced solder mask 4 minus the diameter of the bottom pad 62 is ≥ 3 mil. For example, in some embodiments, the diameter of the semi-plug hole 13 is The diameter of the bottom pad 62 is 12mil. 22mil, the diameter of the reinforced solder mask 4 26mil, the diameter of the reinforced solder mask 4 - Diameter of bottom pad 62

[0036] In some embodiments not shown in the figures, the reinforced solder mask layer 4 can be in various shapes such as a triangle, a quadrilateral, a pentagon, etc., and the underlying pad 62 can also be in various shapes such as a triangle, a quadrilateral, a pentagon, etc., as long as the edge of the reinforced solder mask layer 4 extends outward beyond the edge of the underlying pad 62.

[0037] In some embodiments of the present invention, reference Figure 1-Figure 2 As shown, the semi-plugged via 6 may further include a top pad 63, which is located on the component mounting surface 11, the via body 61 is electrically connected to the top pad 63, and the top pad 63 is electrically connected to the heat dissipation pad 2. The top pad 63 may be formed by folding the top end of the via body 61 outward, and the bottom pad 62 may be formed by folding the bottom end of the via body 61 outward. The semi-plugged via 6 is a conductor as a whole, for example, the semi-plugged via 6 may be copper or aluminum.

[0038] In some embodiments, Figure 2 As shown, the top layer pad 63 and the heat dissipation pad 2 can be constructed as an integral part, that is, the semi-plugged via portion 6 and the heat dissipation pad 2 can be constructed as an integral part.

[0039] In some embodiments of the present invention, reference Figure 1 As shown, the thickness of the reinforced solder mask 4 is H3, H3 = 0.3mil-0.7mil. For example, optionally, the thickness H3 of the reinforced solder mask 4 can be 0.3mil, 0.4mil, 0.5mil, 0.6mil, 0.7mil. Of course, the thickness H3 of the reinforced solder mask 4 can also be other values ​​between 0.3mil-0.7mil, which are not listed here one by one.

[0040] In some embodiments of the present invention, reference Figure 2-Figure 3 As shown, a single heat dissipation pad 2 corresponds to a plurality of half-plug holes 13 , which is beneficial to increase the air volume at the heat dissipation pad 2 , thereby improving the heat dissipation efficiency of the heat dissipation pad 2 and preventing the parts at the heat dissipation pad 2 from being damaged due to excessive temperature.

[0041] In some embodiments of the present invention, reference Figure 1, Figure 3 As shown, the number of the reinforced solder mask layer 4 and the half-plugged holes 13 are consistent and their positions correspond one to one, which can save the amount of the reinforced solder mask layer 4 and reduce the weight of the circuit board.

[0042] In some embodiments of the present invention, reference Figure 1-Figure 2 As shown, a top solder mask 5 is provided on the component mounting surface 11. The top solder mask 5 is a non-conductive material, and the top solder mask 5 avoids the heat dissipation pad 2. Figure 1 As shown, the heat dissipation pad 2 is exposed from the top solder mask layer 5 , which will not affect the electrical connection between the component and the heat dissipation pad 2 .

[0043] In some embodiments of the present invention, reference Figure 1 As shown, the thickness of the top solder mask 5 is H1, and the thickness of the bottom solder mask 3 is H2, H1 = 0.3mil-0.7mil, H2 = 0.3mil-0.7mil. For example, optionally, the thickness of the top solder mask 5 and the bottom solder mask 3 can be 0.3mil, 0.4mil, 0.5mil, 0.6mil, 0.7mil. Of course, the thickness of the top solder mask 5 and the bottom solder mask 3 can also be other values ​​between 0.3mil-0.7mil, which are not listed here one by one.

[0044] In some embodiments of the present invention, the top solder mask layer 5 and the bottom solder mask layer 3 are solder mask ink layers, and the reinforced solder mask layer 4 is a printed ink layer. Ink with printed text can be used to print on the outside of the bottom solder mask layer 3 at the position corresponding to the half-plug hole 13 to form the reinforced solder mask layer 4.

[0045] In some embodiments of the present invention, the top solder mask 5 and the bottom solder mask 3 are green oil layers, and the reinforced solder mask 4 is a white oil layer. White oil is often used to print text outside the green oil layer. The reinforced solder mask 4 is formed by using white oil, which can make full use of the original production and manufacturing equipment of the circuit board without adding additional equipment, that is, the printing of the reinforced solder mask 4 is completed in the process of printing text, which is conducive to saving the manufacturing cost of the circuit board. At the same time, the color difference between white oil and green oil is large. When the white oil is printed unevenly, it can be discovered in time, so that it is convenient to add the reinforced solder mask 4 to the position of the half-plug hole 13 to enhance the blocking effect of the half-plug hole 13 and prevent tin leakage at the half-plug hole 13. The reinforced solder mask 4 can also be called white silk screen.

[0046] In some embodiments, the process flow of the circuit board can be: inner layer → pressing to form the circuit board body 1 → drilling heat dissipation holes → electroplating → forming the heat dissipation pad 2 and the semi-plug hole conductive part 6 → forming the bottom solder mask 3 and the top solder mask 5 → using white oil to form a reinforced solder mask 4, and using white oil to print text at the target position → surface treatment → molding → electrical testing → finished product inspection → packaging and shipment.

[0047] The order of equipment used in the process flow of circuit boards can be: printer → solder paste printing inspection machine → high-speed placement machine → general-purpose machine → reflow oven → optical solder joint inspection machine → printer → solder paste printing inspection machine → high-speed placement machine → general-purpose machine → reflow oven → optical solder joint inspection machine.

[0048] A display device according to another embodiment of the present invention includes the circuit board of the above embodiment.

[0049] According to the display device of the embodiment of the present invention, a reinforced solder mask 4 is added at a corresponding position at the bottom of the semi-plug hole 13, so that the semi-plug hole 13 of the circuit board is well sealed and tin leakage does not occur, thereby preventing the problem of poor welding and reduced mounting accuracy caused by tin leakage during welding, so that the mounting accuracy of the circuit board is higher and the yield rate is higher.

[0050] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0051] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A circuit board, characterized in that: include: A circuit board body, one side of the circuit board body is a part mounting surface, the other side of the circuit board body is a base surface, a heat dissipation pad is arranged on the part mounting surface, a heat dissipation hole is opened on the circuit board body from the base surface to the heat dissipation pad, a bottom solder mask is arranged on the base surface, the bottom solder mask is a green oil layer, the bottom solder mask flows into the heat dissipation hole so that the heat dissipation hole is formed into a semi-plug hole, a reinforced solder mask is arranged outside the bottom solder mask, the reinforced solder mask covers the semi-plug hole, and the reinforced solder mask is a white oil layer; A semi-plugged hole conductive part is provided at the semi-plugged hole, the semi-plugged hole conductive part comprises a conductive part body located in the semi-plugged hole, a bottom pad located on the substrate surface, the conductive part body is electrically connected to the heat dissipation pad, the bottom pad is electrically connected to the conductive part body, the bottom solder mask covers the bottom pad, and the reinforcing solder mask covers the bottom pad from the outside of the bottom solder mask; Wherein, after forming the bottom solder mask layer, white oil is used to form the reinforced solder mask layer, and the white oil is also used to print text at the target position.

2. The circuit board according to claim 1, characterized in that: The semi-plugged via further comprises a top-layer pad located on the component mounting surface, the via body is electrically connected to the top-layer pad, and the top-layer pad is electrically connected to the heat dissipation pad.

3. The circuit board according to claim 1, characterized in that: The thickness of the reinforced solder mask is 0.3mil-0.7mil.

4. The circuit board according to claim 1, characterized in that: The number of the half-plugged holes corresponding to a single heat dissipation pad is multiple.

5. The circuit board according to claim 4, characterized in that: The number of the reinforced solder resist layers is consistent with that of the semi-plugged holes, and their positions correspond one to one.

6. The circuit board according to claim 1, characterized in that: A top solder mask is provided on the component mounting surface, and the top solder mask avoids the heat dissipation pad.

7. The circuit board according to claim 6, characterized in that: The thickness of the top solder mask layer and the bottom solder mask layer is 0.3 mil-0.7 mil.

8. The circuit board according to claim 6, characterized in that: The top solder mask layer is a green oil layer.

9. A display device, characterized in that: A circuit board comprising any one of claims 1-8.

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