High-density hdi board capable of interconnecting any layer

[Patent Abstract] The present invention provides a high-density HDI board that can be interconnected in any layer, comprising: an inner layer board, the inner layer board is provided with a plurality of buried holes, on the upper and lower sides of the inner layer board Separately disposed with a plurality of outer plates having the inner plate as a symmetrical plate; each of the outer plates is provided with a plurality of tapered blind holes, and the number of the tapered blind holes is from the outer plate The direction of the inner layer plate is successively decreased, and the tapered blind holes on the outer layer plate contacting the inner layer plate are in one-to-one correspondence with the position and the number of the buried holes. Since the utility model adopts a tapered blind hole, and the layered superimposed manner is used to make each layer of the tapered blind holes correspondingly combined, the problem that the hole depth of the blind hole and the vertical and horizontal apertures are relatively high is effectively avoided, and the drilling is facilitated. The hole also improves the exchange capacity of the syrup when the hole is metallized, avoids the occurrence of copper in the hole, improves the quality of the circuit board, and reduces the scrap rate.

[Patent Description] - a high-density HDI board that can be interconnected at any level

[Technical Field]

[0001] The utility model relates to a printed circuit board, which is specifically designed as a high-density HDI board which can be interconnected at any layer.

【Background technique】

[0002] The HDI circuit board is also called a high-density interconnection board, and is a circuit board with a relatively high distribution density of micro-blind buried holes technology, which can reduce the production cost, increase the line density, and reliability of the multilayer PCB board. High and good electrical performance.

[0003] At present, in the PCB product design process, in order to meet the needs of the terminal electronic products to the greatest extent, a relatively complicated electrical connection design is usually adopted, the most prominent of which is any layer interconnection, specifically two adjacent layers or Electrical interconnections are made between the multilayer lines through blind holes. However, the apertures of the blind holes in the HDI board of this structure are mostly 0.15 mm and 0.20 mm. For any layer of interconnected PCB, the following quality hazards exist in this design:

[0004] 1. The hole depth of the blind hole is relatively high in the vertical and horizontal directions of the aperture, and the laser drilling cannot be realized. However, it is easy to drill through the copper layer at the bottom of the hole by using the depth-controlled mechanical drilling, and the depth of the depth control needs to be adjusted multiple times. Prone to open circuit risks and increased production costs for drilling;

[0005] 2. The hole depth of such a blind hole is relatively high in the longitudinal and lateral directions of the aperture. The exchange capacity of the syrup is extremely poor when the hole is metallized, and the copper-free condition is likely to occur in the hole, resulting in high rejection rate of the circuit board and affecting cost control.

Utility model content

[0006] Therefore, the purpose of the present invention is to provide a high-density HDI board that can be interconnected in any layer, so as to solve the problem that the hole depth and the aperture of the blind hole are relatively high in the current HDI board, and the drilling is difficult. The risk of opening the road is high and there is no copper in the hole, and the scrapping rate of the circuit board is high.

The object of the present invention is achieved by the following technical solutions.

[0008] A high-density HDI board interconnected by any layer, comprising: an inner layer board, a plurality of buried holes are disposed on the inner layer board, and a plurality of buried holes are respectively disposed on upper and lower sides of the inner layer board The inner layer plate is a plurality of outer layer plates of the symmetrical plate; each of the outer layer plates is provided with a plurality of tapered blind holes, and the number of the tapered blind holes is decreased from the outer layer plate toward the inner layer plate. And the tapered blind hole on the outer layer plate contacting the inner layer plate has a one-to-one correspondence with the position and the number of the buried holes.

[0009] Preferably, the number of tapered blind holes on the adjacent outer layer plate is successively decreased by one from the outer layer plate toward the inner layer plate, and the tapered blind hole on the inner outer layer plate is on the outer outer layer plate. There is a conical blind hole corresponding thereto, and the two conical blind holes are the same size and are on the same straight line.

[0010] Preferably, there is further provided a through hole penetrating the inner layer board and the outer layer board.

[0011] Preferably, the buried via is filled with a resin.

[0012] Preferably, the inner layer plate and the outer layer plate are insulating dielectric layers having a copper foil layer on both sides.

[0013] Compared with the prior art, the utility model has the beneficial effects that the high-density HDI board which can be interconnected by any layer is provided by the utility model, and the inner layer board is provided with a buried hole on each outer layer board. Correspondingly, there are tapered blind holes, and the number of tapered blind holes is gradually decreased from the outside to the inside, and the number of buried holes on the inner layer and the tapered blind holes on the inner side of the inner layer are located on the outer outer layer. The number and position of the tapered blind holes on the plate correspond to one-to-one. Since the utility model adopts a tapered blind hole, and the layered superimposed manner is used to make each layer of the tapered blind holes correspondingly combined, the problem that the hole depth of the blind hole and the vertical and horizontal apertures are relatively high is effectively avoided, and the drilling is facilitated. The hole also improves the exchange capacity of the syrup when the hole is metallized, avoids the occurrence of copper in the hole, improves the quality of the circuit board, and reduces the scrap rate.

[Patent Drawing]

 

[Description of the Drawings]

1 is a schematic cross-sectional structural view of a high density HDI board of the present invention.

[0015] The identification in the figure shows: inner layer board 10, buried hole 11, buried hole 12, copper layer 13, copper layer 14, outer layer board 20, tapered blind hole 21, copper layer 22, outer layer plate 30, cone The blind hole 31, the copper layer 32, the outer layer plate 40, the tapered blind hole 41, the copper layer 42, the outer layer plate 50, the tapered blind hole 51, the copper layer 52, and the through hole 60.

【Detailed ways】

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0017] The utility model provides a high-density HDI board which can be interconnected by any layer, which is mainly used for solving the high vertical and horizontal holes of the hole hole and the aperture of the blind hole in the current HDI board, and the drilling is difficult and open. The risk is high and there is no copper in the hole, and the circuit board has a high scrap rate.

[0018] The utility model comprises: an inner layer board and a plurality of outer layer boards on the lower two sides of the inner layer board, and the outer layer board on the side of the inner layer board and the outer layer board of the lower side layer are The symmetrical plates are symmetrical, that is, the number of outer plates on the upper and lower sides of the inner layer is the same and the same size.

[0019] The inner layer board and the outer layer board, and the outer layer board and the outer layer board are laminated together by a prepreg, and copper is disposed on the upper and lower sides of the inner layer board and each outer layer board. a layer, the inner layer plate is provided with buried holes, each of the outer layer plates is provided with a tapered blind hole, the number of the tapered blind holes is successively decreased from the outer layer plate toward the inner layer plate, and the inner layer plate The tapered blind holes on the outer layer of the contact plate are in one-to-one correspondence with the position and the number of the buried holes, and at the same time, it is ensured that the buried holes on the inner layer plate after lamination are in line with the tapered blind holes on the outer layer plate, And the buried hole is correspondingly filled with a resin.

[0020] Both the tapered blind holes and the buried holes are subjected to hole metallization treatment so that the inner walls of the holes are formed to form a copper layer communicating with the upper and lower layers to achieve communication between the copper layers on different layers.

[0021] In the embodiment of the present invention, a six-layer board is taken as an example for description. Please refer to FIG. 1 , which is a schematic cross-sectional structural view of the high-density HDI board of the present invention.

[0022] The HDI board of the present invention is provided with a through hole 60 extending through the entire board. The inner layer board 10 of the present invention is provided with a buried hole 11 and a buried hole 12, and the buried hole 11 and the buried hole 12 are filled. There is a resin, a copper layer 13 is disposed on the upper side of the inner layer plate 10, and a copper layer 14 is disposed on the lower side surface. The copper layer 13 and the copper layer 14 can be realized through the buried holes 11 and the copper layer of the inner wall of the buried hole 12. The connection between the two.

[0023] The inner layer plate and the outer layer plate described herein are all insulating dielectric layers having a copper foil layer on both upper and lower sides.

[0024] The outer layer plate 20 is correspondingly bonded to the upper side of the inner layer plate 10, and the outer layer plate 20 is provided with two tapered blind holes 21, wherein one of the tapered blind holes 21 corresponds to the buried hole 11. Directly above, the two are on the same straight line, and a copper layer 22 is disposed on the upper side of the outer layer plate 20. The copper layer 22 and the copper layer 13 can be connected through the copper layer of the inner wall of the hole of the tapered blind hole 21. [0025] The outer layer plate 20 is also bonded with an outer layer plate 30. The outer layer plate 30 is provided with three tapered blind holes 31, and two of the tapered blind holes 31 are correspondingly located in the tapered blind holes 21. Directly above, and respectively on the same straight line, a copper layer 32 is disposed on the upper side of the outer layer plate 30, and the copper layer 32 and the copper layer 22 can be connected through the copper layer of the inner wall of the hole of the tapered blind hole 31.

As can be seen from the above description, in the present embodiment, the connection between the copper layer 32 and the copper layer 22 is achieved by the three tapered blind holes 31 between the outer layer plate 30 and the outer layer plate 20, and the outer layer plate 20 and the inner layer plate 10 are connected. The connection between the copper layer 22 and the copper layer 13 is achieved by the two tapered blind holes 21, and the copper layer 13 and the copper layer 14 on the upper and lower sides of the inner layer plate 10 are connected through the buried hole 11 and the buried hole 12.

[0027] The outer layer plate 40 is correspondingly bonded to the lower side of the inner layer plate 10, and the outer layer plate 40 is provided with two tapered blind holes 41, wherein one of the tapered blind holes 41 corresponds to the buried hole 12. Directly above, the two are on the same straight line, and a copper layer 42 is disposed on the lower side of the outer layer plate 40, and the copper layer 42 and the copper layer 14 can be connected through the copper layer of the inner wall of the hole of the tapered blind hole 41.

[0028] The outer layer plate 40 is further bonded with an outer layer plate 50. The outer layer plate 50 is provided with three tapered blind holes 51, and two of the tapered blind holes 51 are correspondingly located in the tapered blind holes 41. Directly below, and respectively on the same straight line, a copper layer 52 is correspondingly disposed on the lower side of the outer layer plate 50, and the copper layer 52 and the copper layer 42 can be connected through the copper layer of the inner wall of the hole of the tapered blind hole 51.

[0029] It can be seen from the above description that the connection between the copper layer 52 and the copper layer 42 is realized by the three tapered blind holes 51 between the outer layer plate 50 and the outer layer plate 40 in the embodiment, and the outer layer plate 40 and the inner layer plate 10 are connected. The connection between the copper layer 42 and the copper layer 14 is achieved by the two tapered blind holes 41, and the copper layer 13 and the copper layer 14 on the upper and lower sides of the inner layer plate 10 are connected through the buried hole 11 and the buried hole 12.

[0030] The above description is merely illustrative of a six-layer board in this embodiment, which is applicable to more than six layers of HDI boards.