Ceramic electronics have the advantages of large ampacity, high thermal conductivity, and excellent dielectric properties which are widely used in power electronics, optoelectronics, automotive industry, and aerospace technology. This work proposes a multimaterial dispensing additive manufacturing technology for customizing the 3D low‐temperature‐cofired ceramic (LTCC) circuitry. Customized LTCC aqueous slurry is first developed and then 3D printed together with commercial silver paste to build the green body. Then, the green body is debinded and sintered with a three‐stage process at 200, 500, and 850 °C, respectively. The shrinkage rate in 3D is around 17% which is comparable with commercial LTCCs. The surface quality of the sintered ceramic is improved obviously compared with that of the green body due to the glazing effect of the glass phase. For the silver conductor, the resistivity and the temperature coefficient of resistance are 2.34 ± 0.04 µΩ cm and 3.56 × 10−3 °C−1, respectively. A serial of demonstrators including 2D, 3D light‐emitting diode ceramic circuit boards and a ceramic heater/thermometer is developed to prove the potential and feasibility of the proposed technology.

With increasing interest in the rapid development of customized ceramic electronics, hybrid additive manufacturing (HAM) technology has become a competent alternative to traditional solutions such as printed circuit boards and cofired ceramic technology. Herein, the novel HAM technology is proposed by combining a dispensing three-dimensional (3D) printing process and selectively laser-activated electroless plating for fabricating 3D fully functional ceramic electronic products. An appropriative 3D-printable and metalizable low-temperature cofired ceramic slurry is developed to build the green body of ceramic electronics. After the debinding and sintering process, the 3D ceramic structure can be selectively laser-activated and then electrolessly plated to achieve electronic functionality. The thickness of the plated copper layer approaches 10 μm after 4 h of plating, and the electrical conductivity is 5.5 × 107 S m–1, which is close to pure copper (5.8 × 107 S m–1). To reduce the surface roughness of the laser-activated ceramic surface and thereby enhance the conductivity of the copper layer, the laser parameters are optimized as a 1250 mm s–1 scan speed, a 0.4 W laser power, and a 20 kHz laser-spot frequency. A high-power 3D light-emitting diode circuit board with an internal cooling channel is successfully developed to prove the feasibility of this HAM technology for customizing fully functional 3D conformal ceramic electronics.

This work proposes a facile and economical hybrid additive manufacturing (HAM)technology combining fused deposition modeling (FDM) 3D printing and laser‐activated selective electroless plating (ELP) for fabricating full functional end‐use 3D customized electronics. A functional acrylonitrile butadiene styrene (ABS) filament doped with dicopper hydroxide phosphate (Cu2(OH)PO4) catalysts is developed for FDM 3D printing. The 3D printed structure is selectively laser‐activated to generate CuI plating seeds on the ABS surface and then electrolessly plated. The poor surface finish, especially the layer lines, is an intrinsic defect of extrusion 3D printing, which not only affected the fabrication quality of the 3D substrates but also the electrical performance of the attached circuitry. Herein, a chemical polishing process based on acetone vapor is explored and characterized to significantly improve the surface quality and thereby the electrical performance of the attached copper layer. In this way, highly conductive metallic circuitry can be freeformly deposited and patterned on the 3D structure which is extremely attractive for customized 3D electronics. To show the application potential of this technology, a 3D conformal 555 timer astable oscillator circuit board and a hot‐wire flowmeter are developed as demonstrators.

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