The extraction of development parameters by using cross-sectional critical shape error method

Abstract

The line-width of semiconductor devices is getting smaller, as the demand of highly density devices is increased. As the minimum feature size is decreased, the difference between real and simulation lithography process is increased and it is difficult to predict the difference. So, there is a need to make this difference as small as possible by inserting exact process parameters fitting for each process in several simulators. It is important that more accurate process parameters are extracted to predict the results of each process by simulation.In order to measure the difference, we first obtained SEM images of several chemically amplified resists, and then, the simulation results were produced by a number of develop parameter set. Subsequently, we used cross-sectional critical shape error (CCSE) method to compare the experimental SEM image with simulation result. By using this CCSE method, we extracted develop parameters of some chemically amplified resist (CAR). Furthermore, we needed to decrease the calculation time greatly to predict a set of more exact develop parameter. We improved the speed of CCSE data treatment by distributing the calculation through several computers and made it possible to manage automatically the new developed CCSE method. This extraction method of develop parameters by using CCSE is easier and gives much better results compares other existing methods.