Switching Element, Method For Manufacturing The Same, And Display Device Including Switching Element

Abstract

A method for manufacturing a switching element which has enough resistance to repeat switching operations and which can be miniaturized and have low power consumption, and a display device including the switching element are provided. The switching element includes a first electrode to which a constant potential is applied, a second electrode adjacent to the first electrode, and a third electrode over the first electrode with a spacer layer formed of a piezoelectric material interposed therebetween and provided across the second electrode such that there is a gap between the second electrode and the third electrode. A potential which is different from or approximately the same as a potential of the first electrode is applied to the third electrode to expand and contract the spacer layer, so that a contact state or a noncontact state between the second electrode and the third electrode can be selected.

What is claimed is: 
     
         1 . A method for manufacturing a switching element comprising:
 forming a first conductive film and a second conductive film over a substrate;   forming a spacer layer so as to cover the first conductive film and the second conductive film:   selectively forming an opening in the spacer layer to expose at least a part of the second conductive film;   forming a sacrificial layer over a part of the spacer layer and the exposed part of the second conductive film;   forming a third conductive film so as to cover the sacrificial layer; and   removing the sacrificial layer so that a gap is formed between the second conductive film and the third conductive film in the opening.   
     
     
         2 . The method for manufacturing a switching element according to  claim 1 , wherein a piezoelectric material is used for the spacer layer. 
     
     
         3 . The method for manufacturing a switching element according to  claim 2 , wherein any one of a crystal (SiO 2 ) film, a lead zirconate titanate (PZT) film, a lithium niobate (LiNbO 3 ) film, a barium titanate (BaTiO 3 ) film, a lead titanate (PbTiO 3 ) film, a lead metaniobate (PbNb 2 O 6 ) film, and a zinc oxide (ZnO) film is used as the piezoelectric material.