Peculiarities of Si films etching in CF4 parent gas

The peculiarities of heat-mass transfer in a radial flow reactor are discussed. Flow structure, temperature of gas mixture and reactive species concentration distribution were studied as a functions of gas flow rate and wafer temperature. The simulations of the reactor incorporated the modeling of the hydrodynamical and molecular transport processes in the etching chamber. The authors considered two-, three- and four-component chemical kinetics. The electron density distribution corresponded to a “diffusion-dominated” discharge. In ther analysis of the calculation data, it was shown that the significant radial gradients of gas temperature appeared and reduced the etching uniformity of the wafer. The distribution of reactive species concentration and etching rate depends on the choice of chemical kinetic model. To choose the kinetic model of the plasma reactor it is necessary to carry out a comparison of calculation data with experimental results