发明名称 |
Method of magnetic tunneling layer processes for spin-transfer torque MRAM |
摘要 |
A method for forming a MTJ in a STT-MRAM is disclosed in which the easy-axis CD is determined independently of the hard-axis CD. One approach involves two photolithography steps and two etch steps to form a post in a hard mask which is transferred through a MTJ stack of layers by a third etch process. Optionally, the third etch may stop on the tunnel barrier or in the free layer. A second embodiment involves forming a first parallel line pattern on a hard mask layer and transferring the line pattern through the MTJ stack with a first etch step. A planar insulation layer is formed adjacent to the sidewalls in the line pattern and then a second parallel line pattern is formed which is transferred by a second etch through the MTJ stack to form a post pattern. Etch end point may be controlled independently for hard-axis and easy-axis dimensions. |
申请公布号 |
US8133745(B2) |
申请公布日期 |
2012.03.13 |
申请号 |
US20070975045 |
申请日期 |
2007.10.17 |
申请人 |
ZHONG TOM;XIAO RONGFU;TORNG CHYU-JIUH;ZHONG ADAM;MAGIC TECHNOLOGIES, INC. |
发明人 |
ZHONG TOM;XIAO RONGFU;TORNG CHYU-JIUH;ZHONG ADAM |
分类号 |
H01L21/00 |
主分类号 |
H01L21/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|