Method for etching Pt film of semiconductor device

摘要

A method for etching a platinum (Pt) layer of a semiconductor device is provided which improves the etching slope of a sidewall of the platinum layer used as a storage node of the semiconductor device. The semiconductor device consists of a semiconductor substrate including a bottom layer on which various other layers are formed. Specifically, according to this invention, a Pt layer is formed on a bottom layer of a semiconductor substrate. An adhesive layer is then formed on the Pt layer while a mask layer is formed on the adhesive layer. After formation of the various layers, the mask layer and adhesive layer are patterned using an etching process to form a mask pattern and an adhesive layer mask pattern, respectively. The semiconductor substrate is then heated and an etching process is performned on the Pt layer using the mask pattern and the adhesive layer mask pattern to form etching slope sidewalls of the Pt layer having etching slopes close to vertical. Accordingly, the Pt electrodes of the semiconductor device of the present invention have a finer pattern than those of the prior art. Finally, overetching is done to remove the mask pattern.