Enhanced Responsivity, Accuracy, and Stability of Aerosol Jet Printing via Mechanical Switching Valve Assisted Internal Shuttering

Aerosol jet printing (AJP) is a promising direct writing (DW) technology based on the gas-driven aerosol. However, the pressure within printhead is hard to be controlled in real time, leading to obvious jet relaxation phenomenon during AJP, which is the critical determinant affecting dimensional accuracy and conformity of printed patterns. In this work, a shuttering system based on an internal mechanical switching valve with special flow channels is proposed to modulate the pressure distribution within printhead, thereby controlling the aerosol jet stream's flow direction in real time to enable faster ON-OFF responsivity and higher printing accuracy. By designing the flow channel geometry of valve, the pressure is maintained constant during ON-OFF switching, fundamentally eliminating jet relaxation time from > 35 s, improving morphological uniformity along entire printed lines, permitting parameter-independent characteristics. With this strategy, the ON-OFF delay due to the dimensions of the two dead zones in AJP system is eliminated by precompensation. Moreover, the stability and universality of this approach are analyzed by repeatedly printing short-line arrays at ON-OFF frequency F = 0.2-50 Hz, aligned endpoints demonstrate the stable high-responsivity ON-OFF control characteristics, which confirms great application prospects of this strategy in high-accuracy manufacturing of complex functional patterns.