High capaciy low cost multi-state magnetic memory

摘要

One embodiment of the present invention includes a multi-state current-switching magnetic memory element includes a stack of two or more magnetic tunneling junctions (MTJs), each MTJ having a free layer and being separated from other MTJs in the stack by a seeding layer formed upon an isolation layer, the stack for storing more than one bit of information, wherein different levels of current applied to the memory element causes switching to different states.

主权项

1. A multi-state current-switching magnetic memory element configured to store a state by current flowing therethrough to switch the state comprising:
a stack of two or more magnetic tunneling junctions (MTJs), each MTJ having a free layer with a switchable magnetic orientation, a barrier layer and a fixed layer, each MTJ of the stack being separated from other MTJs in the stack by at least one amorphous isolation layer, the stack operable to store more than one bit of information with each MTJ storing one bit of information, each of the free layers having a different composition based on the amount of oxide therein, and each of the free layers of the stack being responsive to a unique switching current based on the composition of the free layer, wherein the free layer switches its magnetic orientation based upon the level of the switching current applied thereto, wherein different levels of current applied to the memory element causes switching to different states.