Controlling dopant concentration in correlated electron materials
Subject matter disclosed herein may relate to fabrication of a correlated electron material (CEM) device. In embodiments, after formation of the one or more CEM traces, a spacer may be deposited in contact with the one or more CEM traces. The spacer may operate to control an atomic concentration of dopant within the one or more CEM traces by replenishing dopant that may be lost during subsequent processing and/or by forming a seal to reduce further loss of dopant from the one or more CEM traces.
1. A method of constructing a device, comprising:
forming a plurality of correlated electron material (CEM) traces over a first level, one or more individual CEM traces of the plurality of CEM traces comprising an electron back-donating material including a dopant; and
forming a spacer to fill at least a portion of a trench separating adjacent individual CEM traces of the plurality of CEM traces including controlling an atomic concentration of the dopant within the one or more individual CEM traces of the plurality of CEM traces at least in part by enabling diffusion of the dopant from the spacer into the one or more individual CEM traces to thereby impart particular impedance switching characteristics within the one or more individual CEM traces of the plurality of CEM traces.
2. The method of claim 1 , wherein the spacer seals the one or more individual CEM traces of the plurality of CEM traces to maintain the atomic concentration of the dopant to be within a range of about 0.1% to about 10.0%.
3. The method of claim 1 , wherein forming the spacer comprises depositing aluminum oxide (Al 2 O 3 ), silicon nitride (SiN) or silicon oxynitride (SiON), or a combination thereof, in an atomic concentration of at least about 50.0%, into the trench separating the adjacent individual CEM traces of the plurality of CEM traces.
4. The method of claim 3 , wherein forming the spacer comprises depositing Al 2 O 3 responsive to exposure of the trench separating adjacent individual CEM traces of the plurality of CEM traces to trimethylaluminum.
5. The method of claim 1 , wherein the spacer is adapted to diffuse the dopant into the one or more individual CEM traces of the plurality of CEM traces to maintain the atomic concentration of the dopant within the one or more individual CEM traces in a range of about 0.1% to about 10.0%.
6. The method of claim 1 , further comprising exposing the one or more individual CEM traces of the plurality of CEM traces to nitrous oxide (N 2 O) or nitric oxide (NO), or a combination thereof, and wherein the spacer is to comprise an atomic concentration of at least about 50.0% of SiN or SiO, or any combination thereof, the spacer to be formed by depositing trimethylsilane, bis(dimethylamino)dimethylsilane, bis(tertiarybutylamino)silane, bis(diethylamino)silane), tris(dimethylamino)silane or tetraethoxysilane (TEOS), or a combination thereof.
7. The method of claim 6 , wherein the spacer comprises a concentration of at least about 50.0% SiN, and wherein the method further comprises exposing the trench separating the adjacent individual CEM traces of the plurality of CEM traces to gaseous ammonia (NH 3 ) concurrent with forming the spacer.
8. The method of claim 6 , wherein the spacer comprises an atomic concentration of at least about 50.0% SiO, and wherein forming the spacer further comprises exposing the trench separating the adjacent individual CEM traces of the plurality of CEM traces to ozone (O 3 ), oxygen (O 2 ), radical oxygen (O*) or water (H 2 O) vapor, or a combination thereof.
9. The method of claim 8 , further comprising exposing the trench separating the adjacent individual CEM traces of the plurality of CEM traces to nitrous oxide (N 2 O) or nitric oxide (NO), or combination thereof, prior to forming the spacer.
10. The method of claim 1 , wherein the controlling occurs during an etching process performed subsequent to the forming the one or more individual CEM traces of plurality of CEM traces over the first level.
11. The method of claim 1 , wherein the one or more individual CEM traces of the plurality of CEM traces comprise the electron back-donating material including the dopant, the dopant comprising carbon or nitrogen or a combination thereof.
12. The method of claim 11 , wherein the controlling the atomic concentration of the dopant within the one or more individual CEM traces of the plurality of CEM traces comprises controlling the atomic concentration of the dopant within the one or more individual CEM traces of the plurality of CEM traces to be within the range of about 0.1% to about 10.0% to thereby impart the particular impedance switching characteristics within the one or more individual CEM traces of the plurality of CEM traces.
13. The method of claim 12 , wherein the spacer is adapted to enable diffusion of the carbon or nitrogen, or the combination thereof, into the one or more individual CEM traces of the plurality of CEM traces to maintain the range of the atomic concentration of the carbon or nitrogen, or the combination thereof, within the one or more individual CEM traces in a range of about 0.1% to about 10.0%.
14. The method of claim 11 , wherein the enabling the diffusion of the dopant from the spacer into the one or more individual CEM traces occurs as part of an etching process performed subsequent to the forming the one or more individual CEM traces of the plurality of CEM traces.
15. The method of claim 1 , wherein the forming the plurality of CEM traces over the first level comprises forming the plurality of CEM traces over an electrically conductive material disposed over an insulating substrate.
16. The method of claim 15 , wherein the electrically conductive material comprises a transition metal or a transition metal oxide, or an alloy thereof.
17. The method of claim 16 , wherein the electrically conductive material comprises Nickel.
18. The method of claim 16 , wherein forming the electrically conductive material comprises forming the electrically conductive material to have an atomic concentration of at least 90% of the transition metal or the transition metal oxide, or the alloy thereof.