Simulation of mesa structures for III-V semiconductors under ion beam etching

An argon Ion Beam Etching (IBE) simulation model has been developed to investigate the mesa profile evolution in III-V semiconductors' technology. Particular attention has been focused on the sputtering yield angular dependence effect, on the influence of the material and 2D-morphology of the mask onto the pattern transfer. Experimental sputtering yield versus ion incidence angle is injected into the simulation model. The equations which govern the surface evolution, stem from the current method of characteristics. The simulated profiles show that the trenching phenomenon can appear by only considering the variation of the sputtering yield versus the etched surface canting. This is obtained when neither the ion reflection nor the electric field line deviation are taken into account. On the other hand, the slope transfer from the mask to the GaAs and InP substrates is studied.