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Abstract The growing demand for flexible and wearable hybrid electronics has triggered the need for advanced manufacturing techniques with versatile printing capabilities. Complex ink formulations, use of surfactants/contaminants, limited source materials, and the need for high‐temperature heat treatments for sintering are major issues facing the current inkjet and aerosol printing methods. Here, the nanomanufacturing of flexible hybrid electronics (FHE) by dry printing silver and indium tin oxide on flexible substrates using a novel laser‐based additive nanomanufacturing process is reported. The electrical resistance of the printed lines is tailored during the print process by tuning the geometry and structure of the printed samples. Different FHE designs are fabricated and tested to check the performance of the devices. Mechanical reliability tests including cycling, bending, and stretching confirm the expected performance of the printed samples under different strain levels. This transformative liquid‐free process allows the on‐demand formation and in situ laser crystallization of nanoparticles for printing pure materials for future flexible and wearable electronics and sensors.
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Self-aligned, inkjet-printed resistors on flexible substrates with excellent mechanical stability, high yield, and low variance
Abstract Resistors are basic yet essential circuit components that must be fabricated with high precision at low cost if they are to be viable for flexible electronic applications. Inkjet printing is one of many additive fabrication techniques utilized to realize this goal. In this work, a process termed self-aligned capillarity-assisted lithography for electronics (SCALE) was used to fabricate inkjet-printed resistors on flexible substrates. Capillary channels and reservoirs imprinted onto flexible substrates enabled precise control of resistor geometry and straightforward alignment of materials. More than 300 devices were fabricated using poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as the resistive material and silver as the electrode material. By varying PEDOT:PSS ink formulation and resistor geometry, resistances spanning from 170 Ω to 3.8 MΩ were achieved. Over 98% of devices were functional and the relative standard deviation in resistance ranged from 3% to 18% depending on resistor length and ink composition. The resistors showed no significant change in resistance after 10 000 cycles of bend testing at 1.6% surface tensile strain. In summary, this work demonstrated a fully roll-to-roll compatible process for inkjet printing resistors with superior properties.
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- PAR ID:
- 10502187
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Flexible and Printed Electronics
- Volume:
- 9
- Issue:
- 2
- ISSN:
- 2058-8585
- Format(s):
- Medium: X Size: Article No. 025006
- Size(s):
- Article No. 025006
- Sponsoring Org:
- National Science Foundation
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