Meizhou, China
Meizhou, China

Time filter

Source Type

Xv H.,BoMin Electronic Co. | Luo X.,BoMin Electronic Co.
Advanced Materials Research | Year: 2014

Blind-via plays a crucial role in interlayer interconnection of printed circuit board. To get the blind via metallized a direct electroplating process has been put forward by the way of a inducing CO2 laser beam irradiating the copper in the bottom of blind via. The method for direct electroplating of copper onto a non-copper platable layer has been investigated in blind via metalization. The regression analysis was used to discuss the laser beam energy in different parameters. The results of electroplated blind via showed that the copper in the bottom of blind via can be induced by CO2 laser, and the induced copper particles ejected to the hole wall plays a role of the conductive film layer that mainly composed of copper by electroless plating or carbon black conductive film during electroplating, plasma used in cleaning blind via can promote the sorption of induced copper particles onto the via wall. © (2014) Trans Tech Publications, Switzerland.

Wang S.,University of Electronic Science and Technology of China | Feng L.,University of Electronic Science and Technology of China | Chen Y.,University of Electronic Science and Technology of China | He W.,University of Electronic Science and Technology of China | And 3 more authors.
Circuit World | Year: 2014

purpose-The purpose of this paper is to form good cutting qualities in glass-epoxy material for opening flexible areas of rigid-flex printed circuit boards (PCB) by ultraviolet (UV) laser cutting.Design/methodology/approach-The cut width and cut depth of glass-epoxy materials were both observed to evaluate their cutting qualities. The heat affected zone (HAZ) of the glass-epoxy material was also investigated after UV laser cutting. The relationships between the cut width and the parameters of various factors were analyzed using an orthogonal experimental design.Findings-The cut width of the glass-epoxy material gradually increased with the increment of the laser power and Z-axis height, while cutting speed and laser frequency had less effect on the cut width. Optimal parameters of the UV laser process for cutting glass-epoxy material were obtained and included a laser power of 6W, a cutting speed of 170 mm/s, a laser frequency of 50 kHz and a Z-axis height of 0.6 mm, resulting in an average cut width of 25 μm and small HAZ.Originality/value-Flexible areas of rigid-flex PCBs are in good agreement with the cutting qualities of the UV laser. The use of a UV laser process could have important potential for cutting glass-epoxy materials used in the PCB industry. © 2014 Emerald Group Publishing Limited.

Chen Y.,University of Electronic Science and Technology of China | Chen Y.,Loughborough University | Gao X.,Loughborough University | Wang J.,Loughborough University | And 5 more authors.
Journal of Applied Polymer Science | Year: 2015

Ball milling was used to decrease the particle size of boron nitride (BN) nanoplates and to form more silylated functionalization of their surface. Such functionalized BN nanoplates enhanced their homogeneous dispersion in polyimide (PI) matrix. Thermal conductivities, thermal stabilities, and dielectric properties were characterized to investigate the particular effects on the performance of PI-based composites with functionalized BN nanoplates. When the concentration of functionalized BN nanoplates increased to 50 wt %, thermal conductivity of the composite increased up to 1.583 W m-1 K-1, and the temperature of final thermal decomposition was improved to 600°C. An increasing trend was found in the dielectric constant of the composites while the dielectric loss decreased with the increase in the fraction. An appropriate fraction of functionalized BN nanoplates in PI-based composites were necessary to meet the requirement of withstanding drilling forces for the interconnecting through holes of flexible circuits. © 2015 Wiley Periodicals, Inc.

Liu J.,Chongqing University | Chen J.,Chongqing University | Zhang Z.,Chongqing University | Yang J.,Chongqing University | And 2 more authors.
Circuit World | Year: 2016

Purpose - 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 current (DC) plating method. Design/methodology/approach - Test boards of printed circuit board (PCB) fragments with BVHs and THs for filling plating are designed. The filling plating is conducted in a DC plating device, and the filling processes and influence factors on filling effect of BVHs and THs are investigated. Dimple depths, surface copper thickness, thermal shock and thermal cycle test are applied to characterize filling effect and reliability. In addition, to overcome thickness, increase of copper on board surface during filling plating of BVHs and THs, a simple process called pattern plating, is put forwarded; a four-layered PCB with surface copper thickness less than 12 fxm is successfully produced. Findings - The filling plating with the new copper electroplating formula is potential to replace the conventional filling process of BVHs and THs of PCB and, most importantly, the problem of thickness increase of copper on board surface after filling process is overcome if a pattern plating process is applied. Research limitations/implications - The dimple depth of BVHs and THs after filling plating is not small enough, though it meets the requirements, and the smallest diameter and largest depth of holes studied are 75 and 200 fxm, respectively. Hence, the possibility for filling holes of much more small in diameter and large in depth with the plating formula should be further studied. Originality/value - The paper introduces a new copper electroplating formula which achieves BVHs and THs filling at one process through a DC plating method. It overall reduces production processes and improved reliability of products resulting in production cost saving and production efficiency improvement. © Emerald Group Publishing Limited.

Li X.,Chongqing University | Liu J.,Chongqing University | Zhang S.,Chongqing University | He W.,University of Electronic Science and Technology of China | And 3 more authors.
Circuit World | Year: 2015

Purpose - This paper aims to develop an ideal technique for the preparation of print circuit boards (PCBs) with ladder conductive lines on practical industrial process lines. Design/methodology/approach - First, the raw materials of ladder copper-clad laminates were prepared by plating double-sided copper-clad laminates with vertical plating line. Second, etching compensation experiments were designed and conducted to set up the relationships between etching compensation and width of conductive lines on ladder line print circuit boards (LLPCBs). Third, to evaluate the process technique for the preparation of LLPCBs through etching compensation, verification experiments were designed and conducted on a practical industrial process line, and the quality of lines on LLPCBs was observed and evaluated. Findings - Under the judgment of the quality of conductive lines on LLPCBs as well as the feasibility with a practical industrial process line, the process technique for the preparation of LLPCBs with etching compensation is a simple and reliable method which has the potential to be applied in the industry. Originality/value - It is the first successful report of a new method that produces LLPCBs with etching compensation and has the potential to be applied in the industry. © Emerald Group Publishing Limited.

Hu Y.,Chengdu University of Technology | He W.,Chengdu University of Technology | Xue W.,Chengdu University of Technology | Tao Z.,Chengdu University of Technology | And 3 more authors.
Applied Mechanics and Materials | Year: 2012

The blind via holes formation by laser drilling is one of the key technologies for demanding high density interconnect printed circuit boards. In this paper, the drilling conditions of drilling the blind via holes and the quality of the drilled holes are examined using a CO2 laser source against the FR4 board without copper foil.We chose laser energy,pulse shot,pulse width and diameter of beam as the experimental parameter. The results showed that laser energy and beam diameter played a more important role on changing the blind vias' diameter than pulse shot and pulse width.While the pulse shot and pulse width take more important role in changing the depth of vias. © (2012) Trans Tech Publications, Switzerland.

Loading BoMin Electronic Co. collaborators
Loading BoMin Electronic Co. collaborators