Effect of the dc field on the near-surface plasma of a highly nonuniform microwave discharge

The effect of the dc electric field on the near-surface plasma of an electrode microwave discharge at pressures of 1?C5 Torr was studied by the emission spectroscopy method. It is shown that the dc field weakly affects the vibrational distribution of nitrogen molecules in the C₃??_u state, but changes the structure of the near-surface plasma (shifting the intensity maxima of the emission bands) and the strength of the microwave field near the electrode surface. It is also found that the ratio between the intensities of bands of different sequences of the second positive system of nitrogen radiated from the same state depends on the position along the discharge axis.