Magnetic Random Access Memory (MRAM) Manufacturing Process for a Small Magnetic Tunnel Junction (MTJ) Design with a Low Programming Current Requirement

摘要

A method of making a magnetic random access memory cell includes forming a magnetic tunnel junction (MTJ) on top of a wafer, depositing oxide on top of the MTJ, depositing a photo-resist layer on top of the oxide layer, forming a trench in the photo-resist layer and oxide layer where the trench has a width that is substantially the same as that of the MTJ. Then, the photo-resist layer is removed and a hard mask layer is deposited on top of the oxide layer in the trench and the wafer is planarized to remove the portion of the hard mask layer that is not in the trench to substantially level the top of oxide layer and the hard layer on the wafer. The remaining oxide layer is etched and the MTJ is etched to remove the portion of the MTJ which is not covered by the hard mask layer.