Optimization of Aerosol Jet Printing for High-Resolution, High-Aspect Ratio Silver Lines

Abstract

Aerosol jet printing requires control of a number of process parameters, including the flow rate of the carrier gas that transports the aerosol mist to the substrate, the flow rate of the sheath gas that collimates the aerosol into a narrow beam, and the speed of the stage that transports the substrate beneath the beam. In this paper, the influence of process parameters on the geometry of aerosol-jet-printed silver lines is studied with the aim of creating high-resolution conductive lines of high current carrying capacity. A systematic study of process conditions revealed a key parameter: the ratio of the sheath gas flow rate to the carrier gas flow rate, defined here as the focusing ratio. Line width decreases with increasing the focusing ratio and stage speed. Simultaneously, the thickness increases with increasing the focusing ratio but decreases with increasing stage speed. Geometry control also influences the resistance per unit length and single pass printing of low-resistance silver lines is demonstrated. The results are used to develop an operability window and locate the regime for printing tall and narrow silver lines in a single pass. Under optimum conditions, lines as narrow as 20 μm with aspect ratios (thickness/width) greater than 0.1 are obtained.

Printable Materials for the Realization of High Performance RF Components: Challenges and Opportunities

“…First, AJP produces much finer resolution. Mahajan et al defined the "focusing ratio" as the flow rate ratio of sheath gas flow rate to carrier gas flow rate [43]; they found that the printed line width decreases as the focusing ratio increases, while the standard deviation from run to run decreases, thus enabling a highly repeatable reduction in feature size. However, DIW with its submicron nozzle diameter enables even finer printing than AJP.…”

High-throughput shadow mask printing of passive electrical components on paper by supersonic cluster beam deposition

“…7 An alternative to the use of liquid inks has been developed in the last decade consisting in the direct writing with gas-phase coating techniques where an atomic vapor or nanoparticles dispersed in a carrier gas are deposited directly or through a shadow mask. 12 Direct writing from the gas phase is a low-cost and high-throughput technology suitable also for 3D substrates; 13 its widespread application is, however, hampered by the lack of acceptable adhesiveness on the substrate and electrical conductivity of the deposited species.…”

Aerosol Jet Printed, Sub‐2 V Complementary Circuits Constructed from P‐ and N‐Type Electrolyte Gated Transistors

“…AJP is an excellent method for additive patterning of various kinds of electronically functional liquid inks, Figure 1 b. [ 3,10,15 ] By optimizing the carrier gas/sheath gas ratio, we controlled the minimum line widths in the range of 30 -50 µm (Figure 1 c). Figures 1 d-f display optical images of a discrete EGT, a completed complementary inverter, and a fi ve stage ring oscillator, respectively.…”