Method for Fabricating Magnetic Multilayers
Original Publication Date: 2002-Apr-10
Included in the Prior Art Database: 2002-Apr-10
Related DocumentsPatent/Patent Application:
A method for fabricating magnetic multilayers as required for high-aspect ratio cladding structures and novel giant magnetoresistance (GMR) heterostructures for use in Magnetic Random Access Memories (MRAM) is described. Cladding structures, which are formed on three sides of a Cu line in the back-end of typical IC processing, present trench fill and step coverage issues that threaten the extendibility of MRAM technologies. In GMR multilayer devices, thickness non-uniformity of the individual layers and rough interfaces tend to degrade the coupling between ferromagnetic layers resulting in a poorly defined high-resistance state and degraded device performance. An atomic layer deposition (ALD) process that achieves conformal side wall depositions with the desired film composition for the barrier/cladding/barrier stack as well as atomically sharp interfaces in GMR multilayers with precision control of layer thickness is described. A method of obtaining the desired NiFe alloy composition using ALD is described. Furthermore, a GMR multilayer structure with all layers consisting of bimetal alloys or oxide materials is described.