ATOMIC LAYER DEPOSITION OF HAFNIUM AND ZIRCONIUM OXIDES FOR MEMORY APPLICATIONS

摘要

Embodiments of the present invention generally relate to non-volatile memory devices and methods of making such memory devices. Methods of forming advanced memory devices, such as ReRAM cells, provide optimal atomic layer deposition (ALD) processes for forming metal oxide film stacks having a metal oxide buffer layer disposed on or over the metal oxide bulk layer. The metal oxide bulk layer comprises a metal rich oxide material and the metal oxide buffer layer comprises a metal poor oxide material. The metal oxide bulk layer has lower electrical resistance than the metal oxide buffer layer because the metal oxide bulk layer is less oxidized or more metallic than the metal oxide buffer layer. In one example, the metal oxide bulk layer comprises a metal rich hafnium oxide material and the metal oxide buffer layer comprises a metal poor zirconium oxide material.