The study of discharge performance was performed for argon, nitrogen, and the H2–C2H5OH gas mixture in a power range from 250 to 1000 W, and a pressure range from 10 to 1000 Pa. With argon, a surface wave at the plasma-quartz interface can be excited above 250 W. The surface wave modes can be identified as m=4 and m=6 with pressures of 10 and 230 Pa. With nitrogen, surface waves propagate in two or more modes superposed with a different value of m below the pressure of 133 Pa. In contrast to the above gases, the H2–C2H5OH gas mixture showed no surface wave generation for power levels up to 1000 W; only a hemisphere plasma with a diameter of 8 cm was observed just above the substrate. The plasma, having a diameter of 160 mm, is uniform below the pressure of 133 Pa in nitrogen discharges, but the plasma density is lower than in argon discharges. The radial distributions of electron density in the quartz tube also prove the existence of surface waves for argon and nitrogen. In addition, the axial distributions of electron density prove that the traveling and standing surface waves can be excited by argon discharges in each case: with or without the short plunger at the top of the setup.