Manufacturing RF switch based on phase-change material

• US 10,476,001 B1
• Filed: 08/14/2018
• Issued: 11/12/2019
• Est. Priority Date: 08/14/2018
• Status: Active Grant

• Current Assignee: Newport Fab, LLC (Tower Semiconductor Limited)
• Original Assignee: Newport Fab, LLC (Tower Semiconductor Limited)
• Inventors: Rose, Jefferson E., Slovin, Gregory P., Howard, David J., DeBar, Michael J., El-Hinnawy, Nabil
• Primary Examiner(s): Seven, Evren
• Application Number:
  US16/103,490
• Time in Patent Office: 455 Days
• Field of Search: None
• CPC Class Codes: H10N 70/021 Formation of the switching material, e.g. layer deposition
• CPC Class Codes: H10N 70/063 by etching of pre-deposited switching material layers, e.g. lithography
• CPC Class Codes: H10N 70/231 based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect
• CPC Class Codes: H10N 70/823 adapted for essentially horizontal current flow, e.g. bridge type devices
• CPC Class Codes: H10N 70/861 Thermal details
• CPC Class Codes: H10N 70/8613 Heating or cooling means other than resistive heating electrodes, e.g. heater in parallel
• CPC Class Codes: H10N 70/8825 Selenides, e.g. GeSe
• CPC Class Codes: H10N 70/8828 Tellurides, e.g. GeSbTe

Abstract

In manufacturing a radio frequency (RF) switch, a heat spreader is provided. A first dielectric is deposited over the heat spreader. A trench is etched in the first dielectric. A heating element is deposited in the trench and over at least a portion of the first dielectric. A thermally conductive and electrically insulating material is deposited over at least the heating element, where the thermally conductive and electrically insulating material is self-aligned with the heating element. A conformability support layer is optionally deposited over the thermally conductive and electrically insulating material and the first dielectric. A phase-change material is deposited over the optional conformability support layer and the underlying thermally conductive and electrically insulating material and the first dielectric.

Claims

1. A method of manufacturing a radio frequency (RF) switch, the method comprising:

providing a heat spreader;

depositing a first dielectric over said heat spreader;

etching a trench in said first dielectric;

depositing a heating element in said trench and over at least a portion of said first dielectric;

depositing a thermally conductive and electrically insulating material over at least said heating element;

substantially planarizing said thermally conductive and electrically insulating material with said first dielectric;

depositing a conformability support layer over said first dielectric and said thermally conductive and electrically insulating material;

depositing a phase-change material over said conformability support layer.

2. The method of claim 1, wherein said conformability support layer comprises a material selected from the group consisting of silicon nitride (Si_XN_Y) and silicon oxide (SiO₂).

3. The method of claim 1, wherein said thermally conductive and electrically insulating material is self-aligned with said heating element.

4. The method of claim 1, wherein said phase-change material comprises a material selected from the group consisting of germanium telluride (Ge_XTe_Y), germanium antimony telluride (Ge_XSb_YTe_Z), germanium selenide (Ge_XSe_Y), and any other chalcogenide.

5. The method of claim 1, wherein said heat spreader comprises a material selected from the group consisting of silicon (Si), aluminum nitride (AlN), aluminum oxide (Al_XO_Y), beryllium oxide (Be_XO_Y), silicon carbide (SiC), diamond, and diamond-like carbon.

6. The method of claim 1, wherein said heat spreader performs as an etch stop during said etching said trench in said first dielectric.

7. The method of claim 1, further comprising depositing a contact uniformity support layer over said phase-change material.

8. The method of claim 1, further comprising:

etching said phase-change material;

depositing a passivation layer over said etched phase-change material.

9. The method of claim 1, further comprising forming a recess in said trench and over said heating element prior to depositing said thermally conductive and electrically insulating material.

10. A method of manufacturing a radio frequency (RF) switch, the method comprising:

providing a heat spreader;

depositing a first dielectric over said heat spreader;

etching a trench in said first dielectric;

depositing a heating element in said trench and over at least a portion of said first dielectric, and forming a recess over said heating element in said trench;

depositing a thermally conductive and electrically insulating material in said recess;

depositing a phase-change material over said first dielectric and said thermally conductive and electrically insulating material.

11. The method of claim 10, further comprising substantially planarizing said thermally conductive and electrically insulating material with said first dielectric prior to said depositing said phase-change material.

12. The method of claim 10, wherein said thermally conductive and electrically insulating material is self-aligned with said heating element.

13. The method of claim 10, wherein said phase-change material comprises a material selected from the group consisting of germanium telluride (Ge_XTe_Y), germanium antimony telluride (Ge_XSb_YTe_Z), germanium selenide (Ge_XSe_Y), and any other chalcogenide.

14. The method of claim 10, wherein said heat spreader comprises a material selected from the group consisting of silicon (Si), aluminum nitride (AlN), aluminum oxide (Al_XO_Y), beryllium oxide (Be_XO_Y), silicon carbide (SiC), diamond, and diamond-like carbon.

15. The method of claim 10, wherein said heat spreader performs as an etch stop during said etching said trench in said first dielectric.

16. The method of claim 10, wherein said heating element comprises a material selected from the group consisting of tungsten (W), molybdenum (Mo), titanium (Ti), titanium nitride (TiN), titanium tungsten (TiW), tantalum (Ta), nickel chromium (NiCr), and nickel chromium silicon (NiCrSi).

17. The method of claim 10, wherein said thermally conductive and electrically insulating material comprises a material selected from the group consisting of aluminum nitride (AlN), aluminum oxide (Al_XO_Y), beryllium oxide (Be_XO_Y), silicon carbide (SiC), silicon nitride (Si_XN_Y), diamond, and diamond-like carbon.

18. The method of claim 10, further comprising depositing a contact uniformity support layer over said phase-change material.

19. The method of claim 10, further comprising:

etching said phase-change material;

depositing a passivation layer over said etched phase-change material.