PCB manufacturing method for conveniently detecting back drilling hole precision

Abstract

The invention relates to the field of printed circuit board manufacturing and specifically relates to a PCB manufacturing method for conveniently detecting back drilling hole precision. According to the method, an open loop conductive annular line is arranged around each back drilling position; after back drilling operation is completed, a universal meter is used for detecting whether the annular line is open or not via detection points; if the annular line is open, the annular line is broken via drilling operation; if the annular line is short circuited, the annular line is not broken via the drilling operation. Via measurement, identification marks of short circuits are written down, and the identification marks indicate numerical values of distance between back drilling holes and annular lines and numbers of layers on which the annular lines are positioned; via common add-and-subtract operation, accurate offset can be known in a visual manner, and back drilling hole precision can be read in a simple and convenient manner. When the back drilling holes are large in quantity, poor quality holes can be identified easily. Via use of the method, simple operation can be achieved, detection cost and man power cost can be greatly lowered, and working efficiency can be improved.

Description

technical field [0001] The invention relates to the field of printed circuit board manufacturing, in particular to a PCB manufacturing method which is convenient for detecting the accuracy of back drilling. Background technique [0002] PCB (Printed Circuit Board), the Chinese name is printed circuit board, also known as printed circuit board. The PCB is a support for electronic components and provides electrical connections for electronic components. The production process of PCB is generally: material cutting → inner layer pattern transfer → inner layer etching → lamination → drilling → sinking copper → whole board plating → outer layer pattern transfer → pattern plating → etching → solder mask → surface treatment → forming processing etc. [0003] In the PCB manufacturing process, especially in the high-speed PCB processing process, in order to prevent signal distortion or delay, it is necessary to drill off the hole wall metal that does not play any connection or trans...

AI Technical Summary

Problems solved by technology

In the actual production and processing process, offsets often occur when back drilling is processed. When the alignment between back drilling and primary drilling is poor, the length of the short line will be larger and smaller at the slightest level, and the drilled line will be broken if it is severe. or broken holes

Not only can't achieve the expected effect, affect the accuracy of back drilling, but also produce defective products, which will increase the cost. This shows the importance of back drilling alignment

[0004] At present, the alignment of back-drilled holes is confirmed mainly through X-ray inspection after back-drilling. This method has the following defects: 1. The offset value of back-drilled holes cannot be accurately known; 2. If each layer has Copper, if the total copper thickness is thicker, the X-ray will not be able to see the offset

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