Patent ID: 7569430
Filing Date: 2009-08-04
Classification: H01L

Abstract:
1. A method of forming a phase changeable structure, the method comprising: forming a lower electrode; forming a phase changeable layer including a chalcogenide on the lower electrode; forming an etch stop layer on the phase changeable layer, the etch stop layer having a first etch rate with respect to a first etching material comprising chlorine; forming a conductive layer on the etch stop layer to obtain a stacked composite, the conductive layer having a second etch rate with respect to the first etching material, the second etch rate being higher than the first etch rate; etching the conductive layer by using the first etching material to form an upper electrode; and etching the etch stop layer and the phase changeable layer by using a second etching material that is substantially free of chlorine to form an etch stop pattern and a phase changeable pattern.