Semiconductor device and method of making the same
A magnetic junction includes a free layer including iron (Fe), the free layer has a first planar surface and a first side surface crossing the first planar surface; a first cap layer on the first planar surface of the free layer; and a protection layer on the first cap layer, wherein the protection layer is 8 angstroms (Å) or less in thickness. The protection layer may include one or more elements selected from the group consisting of Ta, Rh, Nb, C, Os, Ir, W, Re, Si, Ru, Ti, and Pt.
1 . A magnetic junction comprising:
a free layer having a first planar surface and a first side surface crossing the first planar surface;
a first cap layer on the first planar surface of the free layer;
a protection layer on the first cap layer; and
a side protection layer on the first side surface of the free layer,
wherein an element of the side protection layer has a higher affinity to the free layer than an element of the first cap layer, and
wherein the element of the side protection layer is directly on the first side surface of the free layer.
2 . The magnetic junction of claim 1 , wherein the protection layer is 1 to 3 angstroms (Å) in thickness.
3 . The magnetic junction of claim 1 , wherein the protection layer comprises one or more elements selected from the group consisting of Ta, Rh, Nb, C, Os, Ir, W, Re, Si, Ru, Ti, and Pt.
4 . The magnetic junction of claim 1 , wherein the protection layer comprises one or more elements selected from the group consisting of Ta, Rh, Nb, and C.
5 . The magnetic junction of claim 1 , wherein the first cap layer comprises MgO, TaO, HfO, ZrO, or AlOx.
6 . The magnetic junction of claim 1 , further comprising a second cap layer between the first cap layer and the protection layer,
wherein the second cap layer is 1 to 8 angstroms (Å) in thickness.
7 . The magnetic junction of claim 6 , wherein the second cap layer comprises Mg or Ti.
8 . The magnetic junction of claim 1 , further comprising a reference layer between the free layer and the first cap layer.
9 . The magnetic junction of claim 8 , wherein the first cap layer comprises Mg or Ti.
10 . The magnetic junction of claim 8 , wherein the first cap layer is 1 to 8 angstroms (Å) in thickness.
11 . A magnetoresistive random-access memory (MRAM) comprising the magnetic junction of claim 1 .
12 . A magnetic junction comprising:
a free layer having a first planar surface and a first side surface crossing the first planar surface;
a first cap layer on the first planar surface of the free layer; and
a side protection layer directly on the first side surface of the free layer,
wherein the side protection layer comprises one or more elements in an elemental form selected from the group consisting of Ta, Rh, Nb, C, Os, Ir, W, Re, Si, Ru, Ti, and Pt, and
the one or more elements of the side protection layer have a higher affinity to the free layer than an element of the first cap layer.
13 . The magnetic junction of claim 12 , further comprising a protection layer on the first cap layer,
wherein the protection layer has the same composition as the side protection layer.
14 . The magnetic junction of claim 13 , wherein the protection layer is 1 to 3 angstroms (Å) in thickness.
15 . The magnetic junction of claim 13 , further comprising a second cap layer between the first cap layer and the protection layer,
wherein the second cap layer comprises Mg or Ti.
16 . The magnetic junction of claim 12 , wherein the first cap layer comprises MgO, TaO, HfO, ZrO, or AlOx.
17 . The magnetic junction of claim 1 , wherein the protection layer is 8 angstroms (Å) or less in thickness.
18 . A method of manufacturing a magnetic junction, the method comprising:
depositing a free layer, the free layer having a first planar surface and a first side surface crossing the first planar surface;
depositing a first cap layer on the first planar surface of the free layer; and
depositing a protection layer on the first cap layer,
wherein the protection layer is 8 angstroms (Å) or less in thickness, and
wherein an element of the protection layer has a higher affinity to the free layer than an element of the first cap layer and is directly on the first side surface of the free layer.
19 . The method of claim 18 , wherein the free layer comprises iron (Fe).
20 . The method of claim 18 , further comprising annealing the magnetic junction after the depositing of the protection layer.
21 . The method of claim 18 , wherein the protection layer comprises an element selected from the group consisting of Ta, Rh, Nb, C, Os, Ir, W, Re, Si, Ru, Ti, and Pt.