Nitrogen doped oxides for lower bandgap
Nitrogen doping an insulating layer can lower the bandgap of a magnetic storage device. It is challenging to nitrogen dope magnesium oxide (MgO). A cation can be added to allow the magnesium to hold onto the nitrogen dopant without highly oxidizing or nitriding the cation. The resulting nitrogen doped MgXO, where X is the cation, has a lower bandgap compared to a much similar barrier layer that has neither nitrogen nor a cation thus improving thermal and electrical reliabilities. The nitrogen doped MgXO is non-stoichiometric whereas comparably, an oxynitride is stoichiometric. Example cations that may be used include aluminum, titanium, vanadium, chromium, and scandium.
1 . A magnetic recording head, comprising:
a first shield;
a second shield; and
a non-stoichiometric, nitrogen-doped MgXO layer disposed between the first shield and the second shield, where X is a cation, wherein the nitrogen-doped MgXO layer is disposed within a spin orbit torque structure, the spin orbit torque structure comprising:
a spin orbit torque (SOT) layer; and
a ferromagnetic layer; wherein the nitrogen-doped MgXO layer is disposed between the SOT layer and the ferromagnetic layer.
2 . The head of claim 1 , wherein the nitrogen is present in an amount of below 10 atomic percent.
3 . The head of claim 2 , wherein the nitrogen is present in an amount of below 5 atomic percent.
4 . The head of claim 1 , wherein X is selected from the group consisting of Al, Sc, Ti, V, Cr, Zn, Zr, Nb, Mo, Ta, Hf, W, and combinations thereof.
5 . The head of claim 1 , wherein the first shield is a leading shield, wherein the second shield is a trailing shield, wherein the head further comprises a main pole, and wherein the spin orbit torque structure is disposed between the main pole and the trailing shield or the leading shield.
6 . The head of claim 1 , wherein the nitrogen-doped MgXO layer is a first nitrogen-doped MgXO layer, wherein the head further comprises a second nitrogen-doped MgXO layer, and wherein the first nitrogen-doped MgXO layer and the second nitrogen-doped MgXO layer are substantially identical.
7 . A magnetic storage device comprising the head of claim 1 .
8 . A spin orbit torque (SOT) device, comprising:
a spin orbit torque (SOT) layer;
a ferromagnetic layer;
a non-stoichiometric first nitrogen-doped MgXO layer disposed between the SOT layer and the ferromagnetic layer, wherein X is a cation; and
a second nitrogen-doped MgXO layer that is disposed between the ferromagnetic layer and an electrode or a shield, or between the SOT layer and an electrode or a shield.
9 . The SOT device of claim 8 , further comprises an interlayer between the SOT layer and the ferromagnetic layer.
10 . The SOT device of claim 8 , wherein X is selected from the group consisting of Al, Sc, Ti, V, Cr, Zn, Zr, Nb, Hf, W, and combinations thereof.
11 . A magnetic storage device comprising the SOT device of claim 8 .
12 . A magnetoresistive random access memory (MRAM) device comprising the SOT device of claim 8 .
13 . The SOT device of claim 8 , wherein the nitrogen is present in an amount of below 10 atomic percent.
14 . A spin orbit torque (SOT) device, comprising:
a first electrode or shield;
a second electrode or shield;
a spin orbit torque (SOT) layer disposed between the first electrode or shield and the second electrode or shield;
a ferromagnetic layer disposed between the first electrode or shield and the second electrode or shield;
a first non-stoichiometric first nitrogen-doped MgXO layer disposed between the first electrode or shield and the second electrode or shield, wherein X is a cation, wherein the first non-stoichiometric first nitrogen-doped MgXO layer is spaced from the SOT layer; and
a second nitrogen-doped MgXO layer that is disposed between the first electrode or shield and the second electrode or shield, wherein the second nitrogen-doped MgXO layer is spaced from the SOT layer, the ferromagnetic layer, and the first non-stoichiometric first nitrogen-doped MgXO layer.
15 . The SOT device of claim 14 , wherein the first non-stoichiometric first nitrogen-doped MgXO layer is disposed between the SOT layer and the ferromagnetic layer.
16 . The SOT device of claim 14 , wherein X is selected from the group consisting of Al, Sc, Ti, V, Cr, Zn, Zr, Nb, Hf, W, and combinations thereof.
17 . The SOT device of claim 14 , wherein the nitrogen is present in an amount of below 10 atomic percent.
18 . The SOT device of claim 14 , wherein the nitrogen is present in an amount of below 5 atomic percent.
19 . A magnetic storage device comprising the SOT device of claim 14 .