ANALYTIC MODEL OF POWER DEPOSITION IN INDUCTIVELY-COUPLED PLASMA SOURCES

A simple analytic model valid for all collisionality regimes is develo ped to describe the power deposition in a cylindrical inductively coup led plasma source with a planar coil. The heating is ohmic at high pre ssures and remains finite at low pressures. The low-pressure collision less heating is due to kinetic nonlocal effects. The model is in good agreement with other calculations of collisionless heating. A diffusio n model is then used to determine the plasma density profile and the e lectron temperature in terms of the gas pressure and the source geomet ry. The heating and diffusion models are used to determine the scaling of the inductive electric field with applied frequency and input powe r, and the results are compared with published experimental data to ve rify the scaling. (C) 1995 American Institute of Physics.