An optimized-based ion etch yield modeling method in plasma etching

摘要

In order to study the physics mechanism of surface etching process in low pressure plasmas, we propose a method to optimize etching yield model, which combines optimization technology with surface evolution algorithm. In plasma etching process, the surface effect of the ions are controlled by etch yield which may be measured by the elaborate experiment. But measuring tool or instrument affect measuring result, which will lead to etch yield model's inaccuracy. In order to avoid the problems caused by measuring method, we adopt optimization technology to calculate the etch yield model. By defining an error function between the actual etching profile and simulation profile, etch yield modeling problem is transformed into an optimization problem; Then we use the genetic algorithm and surface evolution algorithm to solve this problem. The experimental results illustrate that simulation profile using the etch yield model by this method is very similar with the actual etching profile in surface topography. It also proves that our proposed method is effective and can be used to model etch yield.