Development of graphite-based conductive patterns by copper electroless plating and electroplating techniques

Abstract

The screen-printing technique has been widely applied in electronic manufacturing field. In this work, graphite is used for fabricating conductive patterns by screen-printing technique. Moreover, enhance the performance of electrical conductivity by electroless plating and electroplating techniques. The study was separated into two parts. Firstly, optimize the mass ratio between graphite and polyvinylidene fluoride (PVDF). In prepared ink from varied mass ratio; 2.0:0.1, 2:0.2, and 2:0.3 respectively. Volume resistivity analysis of conductive patterns, it was found that the mass ratio between graphite and PVDF of 2: 0.2 provided the lowest volume resistivity of 0.0122 Ω-m. In other cases, the mass ratio between graphite and PVDF of 2:0.1 and 2:0.3 provided volume resistivity of 0.8693 and 0.6445 Ω-m, respectively. Secondly, this part of to study focuses on the factors affecting to improve conductivity efficiency by using electroless plating and electroplating techniques. Electroless plating was found concentration ratios between copper (II)sulfate(CuSO4) and formaldehyde(HCOH) of 1:2 provided the dispersion of spherical small copper better than concentration ratios between CuSO4 and HCOH of 1:1 and 2:1, respectively. Electroplating was found the concentration of electrolytes unaffected to the copper layer at the constant current rate for the process also when the duration of electroplating increase in the copper layer of the pattern increased, within 15 min after electroplating the volume resistivity of conductive patterns reduced to 0.8906 μΩ-m.