Under atmospheric pressure, an apparently homogeneous and stable plasma can be generated from an insulator barrier rf plasma generator of which contains an rf powered cathode and a grounded anode covered with a dielectric insulating material. This is a structure in which the dielectric materials are covered and arranged in parallel in the one side of electrode. In order to characterize the generating plasma under atmospheric pressure, some basic characteristics have been evaluated by the Langmuir probe method as well as by optical emission spectroscopy. From the result of plasma characteristics, the generated plasma was verified to be non-equilibrium; T(electron)>T(excitation)>T(vibration)>T(gas). We tried to apply this to etching of an Zinc oxide(ZnO) films also.