Spin-torque MRAM: spin-RAM, array

• US 20080266943A1
• Filed: 04/24/2007
• Published: 10/30/2008
• Est. Priority Date: 04/24/2007
• Status: Active Application

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Applied Spintronics, Inc., MagiQ Technologies, Incorporated
• Inventors: Yang, Hsu Kai, Wang, Po-Kang
• Granted Patent: US 7,852,662 B2
• Time in Patent Office: Days
• US Class Current: 365/171
• CPC Class Codes: G11C 11/16 using elements in which the storage effect is based on magnetic spin effect

Abstract

A spin-torque MRAM array has MRAM cells arranged in rows and columns. Bit lines are connected to each of the MRAM cells on each column. Source select lines are connected to each MRAM cell of a pair of rows and are oriented orthogonally to the bit lines. Write lines are connected to the gate of the gating MOS transistor of each MRAM cell of the rows. The MRAM cells are written in a two step process with selected MRAM cells written to a first logic level (0) in a first step and selected MRAM cells written to a second logic level (1) in a second step. A second embodiment of the spin-torque MRAM array has the bit lines commonly connected together to receive the data and the source select lines commonly connected together to receive an inverse of the data for writing.

Claims