MODELING AND SIMULATION OF PROFILE ABERRATIONS RESULTING FROM DRY-ETCHING OF POLYSILICON FOR CRITICAL GATE LEVELS

Major profile aberrations occurring during dry etching of poly-silicon are described by a simplified etch rate model and simulated by the 3D profile simulator MASTER. The etch model takes passivation processes and the respective back-etching of the passivation layer into account. The simulations reproduce typical effects like side wall bowing, notc hing during the overetch, and aspect ratio dependences like microloadi ng and inverse microloading. Connecting MASTER with our lithography si mulator SOLID, the combined influence of lithography and etching on pr oximity effects is analysed.