Method for use in making electronic devices having thin-film magnetic components
View Patent ↗Disclosed herein is a method of forming electronic device having thin-film components by using trenches. One or more of thin-film components is formed by depositing a thin-film in the trench followed by processing the deposited thin-film to have the desired thickness.
1. A method of forming a device, comprising:
providing a substrate;
depositing a trench layer on the substrate;
etching the trench layer to form a trench, wherein a portion of the substrate is exposed at the bottom of the trench;
depositing a tunnel junction layer on the trench layer and on the portion of the substrate;
depositing a stack of thin films such that the tunnel junction layer separates the stack of thin films from the trench layer; and
processing the deposited stack of thin films and the trench layer to form a plurality of thin-film components of the device, at least a first portion of the deposited stack of thin films being in the trench.
2. The method of claim 1 , wherein at least one of the plurality of thin-film components is positioned on top of at least another one of the plurality of thin-film components.
3. The method of claim 1 , wherein processing the deposited stack of thin films and the trench layer further comprises removing a second portion of the deposited stack of thin films and a portion of the tunnel junction layer such that a total thickness, including a first thickness of the plurality of thin-film components within the trench and a second thickness of the tunnel junction layer within the trench, is substantially the same as a depth of the trench.
4. The method of claim 1 , wherein the step of processing the deposited stack of thin films comprises processing the deposited stack of thin films and the trench layer using a chemical-mechanical-polishing technique.
5. The method of claim 1 , wherein the first portion of the deposited stack of thin films is deposited on the tunnel junction layer.
6. The method of claim 1 , wherein the plurality of thin-film components comprises a free magnetic layer and a thermal barrier for preventing thermal leakage from the free magnetic layer.
7. The method of claim 6 , wherein the thermal barrier is outside the trench.
8. The method of claim 1 , wherein the plurality of thin-film components comprises a fixed magnetic layer and a thermal barrier for preventing thermal leakage from the fixed magnetic layer.
9. The method of claim 8 , wherein the thermal barrier is outside the trench.
10. The method of claim 1 , wherein the trench has a lateral characteristic dimension of 65 nanometers or less.
11. The method of claim 1 , wherein the trench has a sloped sidewall covered by the tunnel junction layer.
12. The method of claim 1 , wherein the device is a magnetic-random-access memory cell.
13. The method of claim 1 , wherein providing the substrate comprises:
providing a sacrificial substrate;
forming another trench, comprising;
depositing another trench layer on the sacrificial substrate; and
forming the another trench in the another trench layer;
forming another plurality of thin-film components of the device in the trench, comprising:
depositing a plurality of thin films, at least a first portion of the deposited thin films being in the trench; and
removing a second portion of the deposited thin films such that the another plurality of thin-film components are within the another trench.
14. The method of claim 13 , further comprising depositing another tunnel junction layer on the another trench layer and on a portion of the sacrificial substrate exposed at the bottom of the trench.
15. The method of claim 14 , wherein depositing the plurality of thin films is such that the tunnel junction layer separates the plurality of thin films from the trench layer.
16. The method of claim 15 , wherein the first portion of the deposited thin films are deposited on the tunnel junction layer.