Magnetic random access memory
View Patent ↗A magnetic random access memory which is a memory cell array including a magnetoresistive effect element having a fixed layer whose magnetization direction is fixed, a recording layer whose magnetization direction is reversible, and a non-magnetic layer provided between the fixed layer and the recording layer, wherein all conductive layers in the memory cell array arranged below the magnetoresistive effect element are formed of materials each containing an element selected from a group including W, Mo, Ta, Ti, Zr, Nb, Cr, Hf, V, Co, and Ni.
1. A magnetic random access memory comprising a memory cell array, the memory cell array comprising:
a magnetoresistive effect element having a fixed layer whose magnetization direction is fixed, a recording layer whose magnetization direction is reversible, and a non-magnetic layer provided between the fixed layer and the recording layer;
a contact plug being placed immediately below the magnetoresistive effect element and being connected with the magnetoresistive effect element;
a first barrier metal film being formed on a side surface and a bottom surface of the contact plug; and
a second barrier metal film being formed on a top surface of the contact plug and having a side surface that is in contact with a side surface of the first barrier metal film,
wherein all conductive layers in the memory cell array arranged below the magnetoresistive effect element are formed of materials each containing an element selected from a group including W, Mo, Ta, Ti, Zr, Nb, Cr, Hf, V, Co, and Ni,
the all conductive layers include the contact plug, the first and second barrier metal films.
2. The memory according to claim 1 ,
wherein a material of the first barrier metal film is the same as a material of the second barrier metal film.
3. The memory according to claim 1 ,
wherein a film thickness of the first barrier metal film is larger than a film thickness of the second barrier metal film.
4. The memory according to claim 1 ,
wherein the contact plug is connected with the recording layer via the first barrier metal film,
a contact area of the contact plug with respect to the recording layer is smaller than an area of the recording layer.
5. The memory according to claim 4 , further comprising:
a cap layer being formed between the recording layer and the first barrier metal film and having a resistance higher than a resistance of the recording layer.
6. The memory according to claim 5 ,
wherein an area of a bottom surface of the cap layer is larger than an area of the top surface of the contact plug.