Question about how to build the "High-K" and "MTJ " model.

[fangyongxinxi]

Dear Sir,
I have question about how to build the high-k and MJT(magnetic tunnel junction ).  I checked the 2008 and 2010 mannal carefully, still confused about the model, cause I hope to build the model by hand.
1. For the femgofe model,  we just change the  MgO lattice slightly, in order to match the Fe [001], I wonder why we do this.
2. For High-k materials in MOS structure, I wonder how to build the Ru-HfO2-Ru, structure. We choose Ru, not other metals, why ? Could you post the Ru-HfO2-Ru script ?

[fangyongxinxi]

hope to get a general guide on how to build the the complex interface model.

[Anders Blom]

Building these structures takes some careful considerations. We'll try to make some tutorial, but there are several things that must be considered in each specific case. For example - precisely as you ask about the MgO - taking care that the X/Y unit cell between the materials is commensurate; this is a fundamental requirement for any calculation of this type.

The choice of the metal can be based on a specific interest in that material, either from expectations of its particular properties, or from a technological manufacturing perspective, but sometimes it can be rather arbitrary

[zh]

Another important issue is the lattice-match when one builds the configuration with an interface.