Contribution of slow waves on production of high-density plasmas by m=0 helicon waves

The contribution of the slow waves (SWs) on high-density plasma production by m=0 helicon waves is investigated in H-2, D-2, He, N-2, Ne, Ar, and Xe p lasmas. The density-jump is observed in all the gases used at optimum exter nal magnetic fields B-0. The measured plasma density n(p) as a function of B-0 peaks at a condition close to the lower-hybrid resonance in H-2, D-2, H e, N-2, and Ne, whereas, the measured dispersion relation indicates the exc itation of helicon wave. Dispersion relation of electromagnetic waves is so lved using dielectric tensor elements of a cold uniform plasma including io n terms, which shows two branches: the SW and fast (helicon) wave. The tran sition from the ionization by SWs, which are excited in the low-density pla sma produced by an antenna induction field, to that by helicon waves has be en predicted to explain the mechanism to produce the high-density plasma in the helicon wave discharges. (C) 1999 American Institute of Physics. [S107 0-664X(99)01512-8].