Observation and Numerical Simulation for Wet Chemical Etching Process of Semiconductor

This paper concerns with the basic investigations on the wet chemical etching of semiconductors. First, a method to observe the etched cross-section of aluminum layer is developed. It is applied to the observation for the cross-section of a test piece etched in a quiescent etchant. The observation successfully makes clear the time variation for the geometry of the etched cross-section, and elucidates the effects of the resist width on the geometry. Secondly, the numerical simulation for the etching process is performed. The simulated geometry of the etched cross-section is confirmed to agree with the observed result, indicating that the present numerical simulation is effectively used to predict the geometry of the etched cross-section.