Drilling of Heterogeneous Multi-layer Printed Circuit Boards: A review

doi:10.3901/JME.2023.03.283

Abstract

Abstract: The hole in the printed circuit board (PCB) is the core unit that realizes the interconnection between the layers and the assembly of electronic components, and mechanical drilling is the main method of making holes in PCBs. Continuous reliable, consistent, and stable machining of high-density and high-quality holes in PCBs is very difficult. The processing theory of heterogeneous multi-layer composite materials involved is complex, and it also poses severe challenges to drilling tools and processing technology. The classification, composition and thermodynamic properties of typical PCB substrates are summarized, and the difficulties faced by the mechanical drilling processing are proposed. The latest research progress of typical PCB hole machining theory is summarized from five aspects: material deformation and fracture, drilling heat, drilling force and torque, hole creation mechanism, and tool failure mechanism. The research status of drill design, drilling processing technology and detection technology are also reviewed. Some existing problems of micro-hole drilling mechanism, optimal design of micro-tools, cryogenic assisted drilling processing and non-destructive detection of hole quality are also described. Combined with the development trend of the new generation of high-end PCB and the requirements of hole fabrication, the research directions that should be focused on in the future of PCB drilling are prospected.

Key words: heterogeneous multi-layer PCBs, drilling mechanism, drill design, processing technology, drilling process detection technology

CLC Number:

TG156

HUANG Xin, WANG Chengyong, HE Yuxing, FANG Gexian, YANG Tao, YAO Junxiong, ZHENG Lijuan. Drilling of Heterogeneous Multi-layer Printed Circuit Boards: A review[J]. Journal of Mechanical Engineering, 2023, 59(3): 283-307.

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