Plasma created and sustained by a surface wave from a partial-coaxial cavity resonator have been studied. In this work, two types of plasma source geometries are compared, (1) a dielectric disk on ground plane structure (DPSW), and (2) a dielectric disk between a parallel plate structure with a holey top plate (HPSW). In both cases, an evanescent electric field is produced from the cavity resonator to a plasma production chamber of 40 mm diameter. Thus, high-density plasma is generated by the interaction of the evanescent field with particles. This work shows that the plasma density and uniformity of the holey-plate structure is higher than that of the dielectric disk structure. For the holey-plate structure, the plasma density is 7.5×1011 cm−3 with an electron temperature of 3 eV at an argon gas pressure of 13 Pa.