Manufacturing method of figure 8 blind hole in printed circuit board

Abstract

The invention discloses a method for manufacturing a figure-eight blind hole in a printed circuit board, which comprises cutting material, etching inner layer circuits, etching out the required aperture diameter of the blind hole by opening copper windows, and using laser laser copper windows to make The blind hole is burned out. When the copper window is laser processed, the size of the aperture is larger than the aperture size, and the energy will extend to the surrounding during the processing. The figure-8 blind hole is made by laser winding. The edge position of the laser aperture and the copper window The distance between the round edges is controlled between 0.5-1.0 mil. After electroplating, acid etching is performed. During the acid etching process, the blind hole area and the circuit are protected by dry film. The dry film is peeled off, the copper surface is bare and leaked for etching by the etching solution, and finally the optical inspection and resistance value test are carried out. The invention can prevent the overlapping area between the two blind holes from being repeatedly laser processed, and ensure the processing quality of the figure-eight blind holes.

Description

technical field [0001] The invention belongs to the technical field of printed circuit boards, and in particular relates to a method for manufacturing a figure-8 blind hole of a printed circuit board. Background technique [0002] In the traditional blind hole laser processing technology, the laser blind hole diameter is generally small, and the thickness of the dielectric layer is thin. 2 Laser processing is easier to process; for some millimeter-wave radars, irregular laser blind holes (“8-shaped blind holes”) need to be opened on the PCB (printed circuit board), and the blind hole aperture and the thickness of the dielectric layer are larger than the traditional blind hole aperture. And the thickness of the dielectric layer increases, so it brings many technical difficulties to the production. [0003] In the traditional blind hole laser processing process, due to the small diameter of the blind hole and the thin thickness of the dielectric layer, the CO 2 Laser process...

AI Technical Summary

Problems solved by technology

[0002] In the traditional blind hole laser processing technology, the aperture of the laser blind hole is generally small, and the thickness of the dielectric layer is thin. For CO 2 Laser processing is easier to process; for some millimeter-wave radars, it is necessary to open irregular laser blind holes ("8"-shaped blind holes) on the PCB (printed circuit board), and the blind hole aperture and dielectric layer thickness are larger than the traditional blind hole aperture. And the thickness of the dielectric layer increases, so it brings many technical difficulties to the production

[0003] In the traditional blind hole laser processing technology, due to the small diameter of the blind hole and the thin thickness of the dielectric layer, the CO 2 Laser processing is also easy to process under the premise of meeting the quality requirements; the irregular blind hole ("8" shaped blind hole) design, there will be some overlapping areas between the two blind holes, and the traditional processing method will cause the overlapping area to be repeatedly lasered Processing causes the bottom of the blind hole to be broken down or the copper at the bottom of the blind hole is separated from the bonding sheet, so it is a technical problem in the blind hole laser processing process

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