A low power plasma generator is provided which can be fabricated in micro-miniature
size and which is capable of efficient portable operation. The plasma generator
comprises a microwave stripline high Q resonant ring, which may be circular or
non-circular, disposed on a dielectric substrate and having a discharge gap in
the plane of the substrate. The resonant ring is one-half wavelength in circumference
at the operating frequency and is matched to the impedance of the microwave power
supply. The voltages at the resonator ends at the gap are 180 out of phase
and create an intense electric field in the gap, and a resultant discharge across
the gap. The discharge is non-thermal and operates near room temperature and has
an intense optical emission. The generator is well suited for low power portable
and other applications and can be readily fabricated by known microcircuit techniques.
Alternatively, the gap of the resonant ring can extend through the substrate and
in which the discharge is formed. A bias coil can be coupled to the ring to provide
a bias voltage to the plasma. A feedback path can be provided for self oscillation
and closed loop frequency control.
