An EVA Cavity-Based Microwave Plasma Jet Array

Cold atmospheric-pressure plasma supports applications in medicine, sterilization, food and water treatment, semiconductor processing, propulsion, and flow control. Conventional plasma jets often depend on high-voltage pulses or high-power RF sources, resulting in systems that can be inefficient, bulky, costly, and difficult to scale. 

A need remains for compact plasma sources that generate stable, high-density cold plasma at low input power and can be manufactured in scalable single-jet or array configurations. 

Invention Description

Researchers at The University of Toledo have developed an evanescent-mode cavity microwave plasma jet that concentrates electromagnetic energy in a small gas-flow region to ignite and sustain cold plasma with low power. This technology expands the platform to printed-circuit-board implementations and multi-jet arrays, enabling compact, manufacturable devices with larger effective plasma volumes. 

Applications

- Plasma medicine and antimicrobial treatment; food, water, and agricultural decontamination; materials and semiconductor processing; propulsion; flow control; and reconfigurable RF electronics. 

Advantages

Power-efficient operation, with plasma sustained at input powers as low as approximately 400 mW in a single-jet prototype. 

• PCB-based configurations support compact, planar fabrication and potential integration into electronic systems. 

• Scalable architecture enables microplasma arrays and larger effective treatment areas. 

• Low gas temperatures and reduced operating voltage may improve safety for temperature-sensitive applications. 

• Controllable plasma output through input power, gas flow rate, frequency, and single-jet or array configuration.