  The semicylindrical microresonator with relatively simple excitation with a
plane wave is studied. The resonator is formed on the base of the
dielectric/metal/dielectric structure, where the wave energy penetrates into
resonator through a thin metal layer and stored in a semicylindrical dielectric
with high permittivity. The proposed microresonator combines features of
Fabry-Perot and Whispering gallery mode resonators. Dependence of radiation
losses on the radius and materials are estimated by theoretical analysis, while
excitation by a plane wave is shown via numerical analysis. The quality
Q-factor of the resonator can achieve up to 104, at a radius of a semicylinder
of several microns.
