Patent ID: 9177627
Filing Date: 2015-11-03
Classification: G11C

Abstract:
1. A method for improving manufacturability or production yield rate of magneto-resistive random access memory (MRAM) comprise at least one the following steps: (1) compensating bias or operation point by using cell-selection circuit board and compensation module through bias compensation method, so as to reduce bias distribution range and increase bias uniformity; (2) excluding outlier cells and bad cells when reading by using cell-selection circuit board and exclusion module for reading through the reading exclusion method; (3) excluding outlier cells and bad cells when writing by using write-jump-over management circuit blocks and exclusion module for writing through write jump-over method; (4) improve stability and uniformity by optimizing magnetic and geometric design of MRAM cells through using shared PL (pinned layer) and AFC (ferro-magnetically coupled layers) with smaller AFM (anti-ferro-magnetism) grain size to increase uniformity, and adjusting FL (free layer) shape anisotropy; and (5) improving write-ability by using same heating current for both heating cells and providing flipping-assistant-field to doubly speed up flipping process of cells.