A Low-Cost and Flexible Microplasma Generation Device to Create Hydrophobic/Hydrophilic Contrast on Nonflat Surfaces

This letter presents a low-cost (<;0.25 USD per device), easy-to-fabricated, and flexible microplasma generation device (MGD), and the use of this device to perform surface patterning. This dielectric-barrier-discharge-type MGD is made of double-side copper clad laminates and the electrode patterns were fabricated by a printed circuit board fabrication-based method, which allows the patterning without lithographic processes with good feature transfer fidelity. The MGD was utilized to create hydrophilic/hydrophobic contrast by a maskless patterning process, either creating hydrophobic patterns on hydrophilic surfaces or hydrophilic pattern on hydrophobic surfaces with sub-millimeter spatial resolution. In the former case, the hydrophobic fluorocarbon polymer (FCP) patterns were deposited on glass using c-C4F8 and He plasmas. In the latter case, hydrophilic patterns were created on a FCP-coated glass substrate using the MGD operated in ambient air. We also demonstrated that the flexibility of the device enabled non-flat surface patterning.