Double-sided stepped hole circuit board and its realization method

Abstract

Disclosed are a method and structures for implementing a circuit board with stepped holes on both surfaces thereof, the method comprising the steps of manufacturing a circuit board with upper-layer blind holes (4, 5) and lower-layer blind holes (8, 9) (S1); pressing copper foils (12, 13) on upper and lower surfaces of the circuit board to cover orifices of the upper-layer blind holes (4, 5) and the lower-layer blind holes (8, 9) (S2); drilling multiple rows of through-holes (6, 7, 10, 11) on the circuit board, and performing electroless copper plating and electroplating for the through-holes (6, 7, 10, 11) (S3); and backdrilling a row of through-holes (6, 10) close to the blind holes (4, 5, 8, 9), and removing the copper foils (12, 13), so as to form, on the circuit board, a stepped-hole region in which the surface of the blind holes (4, 5, 8, 9) thereof, the surface of the row of through-holes (6, 10) close to the blind holes (4, 5, 8, 9) and the surface of the other through-holes (7, 10) are step-shaped (S4).

Description

technical field [0001] The invention relates to the printed circuit board technology of communication equipment, in particular to a double-sided stepped hole circuit board and a realization method thereof. Background technique [0002] In modern communication equipment, the backplane provides the physical and electrical interconnection between modules in the same equipment. With the development of technology and the sharp increase of users' demand for bandwidth, the data link rate between the line card and the switch card in the communication equipment is getting higher and higher, which is constantly challenging the limit of the transmission rate of the backplane. A considerable part of the backplane High-density connectors need to be used to connect line cards and switch cards, and the stepped holes on the backplane are determined by the connector type. [0003] In the field of communications, as operators continue to improve their business service levels, electronic prod...

AI Technical Summary

Problems solved by technology

[0005] In practical applications, it is found that the same device in the prior art cannot coexist with through holes and blind holes. If through holes and blind holes coexist, there are at least the following disadvantages: During the hole processing process, there will be liquid residue in the blind hole, which will affect the long-term reliability of the product; ②The distance between the through hole and the blind hole is too large, and high-density pitch devices cannot be used; ③When the blind hole area is torn to protect the copper foil, the blind hole area is easy to Torn apart, affecting product reliability

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