Etching method for making chalcogenide memory elements

Abstract

The present invention provides an improved method for forming a memory element having a chalcogenide layer such as Ge2Sb2Te5. A substrate having a dielectric etch stop layer, a chalcogenide layer, an anti-reflective layer and a mask layer is placed in a vacuum chamber having a high density plasma source. At least one chlorine containing gas, such as a mixture of BCl3 and Cl2, is introduced into the vacuum chamber for etching the chalcogenide layer and the anti-reflective layer to the dielectric etch stop layer. The etch process is discontinued based on an endpoint detection system. Upon completion of the etch process, the substrate is removed from the vacuum chamber and the mask layer is stripped from the substrate.

Description

[0001] This application is related to and claims priority to commonly owned US Provisional Patent Application No. 60 / 488,921, filed July 21, 2003, entitled "Plasma Etching of GeSbTe Films," which is incorporated by reference. technical field [0002] The present invention generally relates to the field of semiconductor devices and fabrication, and more particularly, the present invention relates to memory elements and methods of making memory elements. Background technique [0003] Chalcogenide material alloys have the ability to transform between amorphous and crystalline phases by applying temperature. The phase transition changes both the electrical and optical properties of the material. Recently, these materials have been introduced into non-volatile memory elements such as phase change memory (OUM). [0004] The common chalcogenide used to produce OUM is Ge x Sb y Te z (GST), where typical values ​​are x=2, y=2 and z=5. With an input of picojoules of energy, the c...

AI Technical Summary

Problems solved by technology

[0008] The prior art does not provide any of the benefits provided by the present invention

Images