The Implementation of the Surface Charging Effects in Three-Dimensional Simulations of SiO_(2) Etching Profile Evolution

Refined control of etched profile in microelectronic devices during plasma etching process is one of the most important tasks of front-end and back-end microelectronic devices manufacturing technologies. A comprehensive simulation of etching profile evolution requires knowledge of the etching rates at all the points of the profile surface during the etching process. Electrons do not contribute directly to the material removal, but they are the source, together with positive ions, of the profile charging that has many negative consequences on the final outcome of the process especially in the case of insulating material etching. The ability to simulate feature charging was added to the 3D level set profile evolution simulator described earlier. The ion and electron fluxes were computed along the feature using Monte Carlo method. The surface potential profiles and electric field for the entire feature were generated by solving Laplace equation using finite elements method. Calculations were performed in the case of simplified model of Ar+/CF4 non-equilibrium plasma etching of SiO2.

Three-Dimensional Simulations with Fields and Particles in Software and Inflector Designs

Particles and fields represent two major modeling paradigms in pure and applied science at all. In this paper a methodology and some of the results for three-dimensional (3D) simulations that include both field and particle abstractions are presented. Electromagnetic field calculations used here are based on the discrete differential form representation of the finite elements method, while the Monte Carlo method makes foundation of the particle part of the simulations. The first example is the simulation of the feature profile evolution during SiO2 etching enhanced by Ar + /CF4 non-equilibrium plasma based on the sparse field method for solving level set equations. Second example is devoted to the design of a spiral inflector which is one of the key devices of the axial injection system of the VINCY Cyclotron.

Application of the Level Set Method in Three-Dimensional Simulation of the Roughening and Smoothing of Substrates in Nanotechnologies

This paper contains results of the comprehensive studies of the effect of the isotropic etching mode on roughening of the nanocomposite materials and on smoothing of the roughed nanostructure made of homogeneous materials. Three-dimensional simulation results obtained illustrate the influence of the isotropic etch process on dynamics of the roughening and smoothing of the surfaces, indicating the opposite effects of the same etch process on the surfaces made of different materials. It was shown that root mean square roughness obeys simple scaling laws during both roughening and smoothing processes. The exponential time dependences of the rms roughness have been determined.