Fabry-Perot interferometry for microplasma diagnostics

A new method for determining the electron density of a thin plasma by means of Fabry-Perot interferometry is proposed. The interferometer consists of two plasma layers and dielectric material surrounded by two plasma layers. The transmittance of electromagnetic waves across the interferometer is calculated, and Fabry-Perot resonances are demonstrated. It is shown that the electron density can be determined from the measurement of the Fabry-Perot resonance frequencies. This method can also be applied to the measurement of conduction electron density in semiconductor films.