Abstract: Fabrication methods using Ion Beam Etching (IBE) for MRAM cell memory elements are described. In embodiments of the invention the top electrode and MTJ main body are etched with one mask using reactive etching such as RIE or magnetized inductively coupled plasma (MICP) for improved selectivity, then the bottom electrode is etched using IBE as specified in various alternative embodiments which include selection of incident angles, wafer rotational rate profiles and optional passivation layer deposited prior to the IBE. The IBE according to the invention etches the bottom electrode without the need for an additional mask by using the layer stack created by the first etching phase as the mask. This makes the bottom electrode self-aligned to MTJ. The IBE also achieves MTJ sidewall cleaning without the need for an additional step.
Type:
Grant
Filed:
December 4, 2013
Date of Patent:
October 20, 2015
Assignee:
Avalance Technology, Inc.
Inventors:
Kimihiro Satoh, Dong Ha Jung, Jing Zhang, Benjamin Chen, Yiming Huai, Rajiv Yadav Ranjan, Yuchen Zhou
Abstract: A method of configuring a computer memory system includes receiving a request from customized software driver or a BIOS extension software or a customized legacy BIOS or a customized UEFI PMM extension software or a customized UEFI BIOS, scanning memory module sockets in response to the request, recognizing memory modules in the memory module sockets, the memory modules being made of, at least in part, persistent memory modules (PMMs), configuring the PMMs to be invisible to the OS, and storing the mapping information to a designated protected persistent memory area, and presenting the PMMs as a persistent block storage to the OS.