Circuit World: Volume 42 Issue 3

PCB welding spot detection with image processing method based on automatic threshold image segmentation algorithm and mathematical morphology

Shi yuan Wang, Yang Zhao, Liuying Wen

To enhance the detection efficiency of printed circuit board (PCB) soldered dot, this study aims to detect PCB soldered dot with image processing method.

Pre-curing investigation of filling conductive paste in prepreg to interconnect two multilayer structures of backboard for press-fit application

Shouxu Wang, Ting Yang, Yuanming Chen, Wei He, Yongsuan Hu, Xinhong Su

The purpose of this paper is to form high density interconnection (HDI) of backboard for press-fit applications with the pre-curing conditions of conductive paste. The best…

Movement characteristics of micro drill bit during entry period in PCB high speed drilling

Hongyan Shi, Qiuxin Yan, Shengzhi Chen

The purpose of this paper is to study the movement characteristics of micro drill bit during entry period in printed circuit board (PCB) high-speed drilling and to present an…

Impedance and resistance of carbon ink during cure

Anthony Samano, Yanmeng Xu, David Harrison, Chris Hunt, Martin Wickham, Owen Thomas

The resistivity of cured conductive ink films are dependent on a wide range of process parameters. An early indication of the resistivity that is likely to result following curing…

Morphology and acoustic artefacts of copper deposits electroplated using megasonic assisted agitation

Thomas D.A. Jones, David Flynn, Marc P.Y. Desmulliez, Dennis Price, Matthew Beadel, Nadia Strusevich, Mayur Patel, Chris Bailey, Suzanne Costello

This study aims to understand the influence of megasonic (MS)-assisted agitation on printed circuit boards (PCBs) electroplated using copper (Cu) electrolyte solutions to improve…

A copper electroplating formula for BVHs and THs filling at one process

Jia Liu, Jida Chen, Zhu Zhang, Jiali Yang, Wei He, Shijin Chen

The purpose of this paper is to introduce a new copper electroplating formula which is able to fill blind microvias (BVHs) and through holes (THs) at one process through a direct…