A kind of blind hole circuit board and its manufacturing method

Abstract

The invention discloses a blind hole circuit board and a manufacturing method thereof. Drill through holes on the board to make blind holes, and thicken the copper layer thickness of the second copper foil of the first copper clad core board by electroplating on the board surface, process the second copper foil into the second circuit layer, and thicken the second copper clad core board Foil the copper layers on both sides of the core board and make the third circuit layer, then laminate the first and second copper clad core boards and prepregs into a whole circuit board; mechanically drill through holes for the laminated whole circuit board And plate a layer of copper, thicken the outer layer of copper foil of the overall circuit board by electroplating on the board surface, and then make the outer layer of the circuit and cover the solder mask layer and then perform surface treatment. Copper-clad core boards with copper foils of different thicknesses, in the process of plated through holes, surface plating and pattern plating, in order to meet the copper thickness requirements of the holes, the copper layer will not be plated too thick, which is convenient for controlling the overall board thickness.

Description

【Technical field】 [0001] The invention relates to the technical field of printed circuit boards, in particular to a blind hole circuit board and a manufacturing method thereof. 【Background technique】 [0002] In the existing printed circuit board technology, for circuit boards with mechanical blind hole design, through holes are usually drilled on the copper clad core board of the blind hole layer, and then the single plated hole process is performed, and then laminated layer by layer. combine. However, in the plating process, the plating process needs to make a plated film one more time, and then plate the hole, remove the film and grind away the copper protruding from the hole when the hole is plated. The process is cumbersome and the copper grinding of the hole is difficult to control, making the production cost higher. ; Instead of using the plating process to directly plate the entire board to make blind hole copper, affected by the electroplating principle, the copper...

AI Technical Summary

Problems solved by technology

However, in the plating process, the plating process needs to make a plated film one more time, and then plate the hole, remove the film and grind away the copper protruding from the hole when the hole is plated. The process is cumbersome and the copper grinding of the hole is difficult to control, making the production cost higher. ; Instead of using the plating process to directly plate the entire board to make blind hole copper, affected by the electroplating principle, the copper thickness on the board surface will be slightly thicker than the copper thickness in the hole after the electroplating is completed, and the copper clad core board with thicker bottom copper is used to make it For circuit boards, in order to meet the specified hole wall copper thickness, the copper layer of the copper clad core board will be too thick during the production process, which will affect the thickness control of the overall finished board after lamination, resulting in the overall finished board thickness exceeding the standard , and the thicker bottom copper is not conducive to the production of circuit boards with smaller line gaps, and will also increase the cost

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