Abstract
Polyimides are a group of high performance thermal stable dielectric materials used in diverse applications. In this article, we synthesized and developed a high-performance polyimide precursor ink for a Material Jetting (MJ) process. The proposed ink formulation was shown to form a uniform and dense polyimide film through reactive MJ utilising real-time thermo-imidisation process. The printed polyimide film showed a permittivity of 3.41 and degradation temperature around 500 °C, both of which are comparable to commercially available polyimide films. Benefiting from the capability of being able to selectively deposit material through MJ, we propose the use of such a formulation to produce complex circuit board structures by the co-printing of conductive silver tracks and polyimide dielectric layers. By means of selectively depositing 4 μm thick patches at the cross-over points of two circuit patterns, a traditional double-sided printed circuit board (PCB) can be printed on one side, providing the user with higher design freedom to achieve a more compact high performance PCB structure.
Highlights
Material Jetting (MJ) is an advanced, high resolution Additive Manufacturing (AM) method, which can be used to produce structures by stacking up material droplets
The poly(amic) acid (PAA) precursor transforms into PI through a thermal imidisation reaction during which water molecules condensates from PAA and form new covalent bonding [16,21]
This formulation was designed for material jetting process, the principle of using polymer precursor followed by chemical reaction to process polymer that has high performance but limited processability could be applied in other kinds of AM techniques to help expand the availability of functional polymeric materials for AM
Summary
Material Jetting (MJ) is an advanced, high resolution Additive Manufacturing (AM) method, which can be used to produce structures by stacking up material droplets. The use of MJ for circuit board manufacturing can simplify the whole production process compared with conventional PCB manufacturing methods, reducing the material waste and production cost especially for low volume products [3] and providing great design freedom [3,4,5,6,7]. This will allow the user to produce bespoke products such as flexible or disposable elecronics [8]. In 2014, Andersson et al fabricated workable double-sided PCBs by laminating two separately printed single-sided PCBs together, presenting one solution to this problem [13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
