Heat flux into the substrate and electric power measurement in radio frequency discharge plasma

We performed measurements of the radio frequency power and temperature of electrodes and plasma parameters of rf discharge. The purpose of this research is to check the accuracy of the measurement of energy consumed in plasmas. The heat energy in plasma was obtained by heat flux that was calculated from substrate temperature. The temperature was measured by a laser interferometer using LiNbO3 crystals. In the case of electrode spacings of 2,3, and 4 cm, the heat energy toward electrodes was 7.7, 5.4, and 4.0 W, respectively. The current and voltage measurement was made at the driven electrode. The input power was 8.2, 5.1, and 7.7 W for electrode spacings of 2, 3, and 4 cm, respectively. The heat energy calculation based on the electron density distribution measured was conducted by estimating the Bohm flux and ambipolar diffusion flux. It was found that the heat energy toward electrode was 1.4 1.8, and 1.5 W for electrode spacings of 2, 3, and 4 cm. respectively, and the heat toward the wall was neglibible. (C) 2006 Wiley Periodicals, Inc.