Multiple layer phase-change memory
View Patent ↗A phase-change memory may be formed with at least two phase-change material layers separated by a barrier layer. The use of more than one phase-change layer enables a reduction in the programming volume while still providing adequate thermal insulation.
1. A method comprising:
forming a pore over a substrate;
forming a sidewall spacer on said pore;
forming a first layer of a phase-change material over said sidewall spacer;
forming a non-phase-change material over said first layer; and
forming a second layer of a phase-change material over said non-phase-change material.
2. The method of claim 1 including forming the first and second layers of the same material.
3. The method of claim 1 including forming the first and second layers of different materials.
4. The method of claim 1 including forming a conductive non-phase-change material.
5. The method of claim 1 including forming a contact over said substrate and forming said sidewall spacer on said contact.
6. The method of claim 5 including contacting said contact with said first layer.
7. The method of claim 1 including forming said first layer to have a thickness between about 300 to 500 Anstroms.
8. The method of claim 7 including forming said non-phase change material to have a thickness of 50 to 200 Angstroms.
9. A method comprising:
forming a pore over a substrate;
forming a sidewall spacer in said pore;
forming a first layer of a phase change material having a first thickness;
forming a non-phase change material over said first layer, said non-phase change material having a second thickness less than said first thickness;
forming a second layer of a phase change material over said non-phase change material such that said first and second layers are completely separated by said non-phase change material; and
forming said first and second layers in said non-phase change material over said sidewall spacer.
10. The method of claim 9 including forming the first and second layers of the same material.
11. The method of claim 9 including forming the first and second layers of different materials.
12. The method of claim 9 including forming a conductive non-phase-change material.
13. The method of claim 9 including forming a contact over said substrate and forming a sidewall spacer on said contact.
14. The method of claim 13 including contacting said contact with said first layer.