PCM RF switch fabrication with subtractively formed heater

• US 10,475,993 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: Slovin, Gregory P., Rose, Jefferson E., Howard, David J., DeBar, Michael J., El-Hinnawy, Nabil
• Primary Examiner(s): Gheyas, Syed I
• Application Number:
  US16/103,646
• Time in Patent Office: 455 Days
• CPC Class Codes: H01L 23/345 Arrangements for heating thermal treatment apparatus H01L21/00
• CPC Class Codes: H01L 23/525 with adaptable interconnections
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H10N 70/023 by chemical vapor deposition, e.g. MOCVD, ALD
• CPC Class Codes: H10N 70/026 by physical vapor deposition, e.g. sputtering
• 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 70/235 between different crystalline phases, e.g. cubic and hexagonal
• CPC Class Codes: H10N 70/823 adapted for essentially horizontal current flow, e.g. bridge type devices
• CPC Class Codes: H10N 70/8413 adapted for resistive heating
• 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 fabricating a radio frequency (RF) switch, a heat spreader is provided and a heating element is deposited. A thermally conductive and electrically insulating material is deposited over the heating element. The heating element and the thermally conductive and electrically insulating material are patterned, where the thermally conductive and electrically insulating material is self-aligned with the heating element. A layer of an upper dielectric is deposited. A conformability support layer is optionally deposited over the upper dielectric and the thermally conductive and electrically insulating material. A phase-change material is deposited over the optional conformability support layer and the underlying upper dielectric and the thermally conductive and electrically insulating material.

Claims

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

providing a heat spreader;

depositing a heating element;

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

patterning said heating element and said thermally conductive and electrically insulating material;

depositing a layer of an upper dielectric;

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

depositing a conformability support layer over said upper 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, further comprising depositing a middle dielectric over said heat spreader prior to depositing said heating element, and wherein said heating element is deposited over said middle dielectric.

3. 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).

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

5. 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.

6. 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.

7. The method of claim 1, wherein said heat spreader performs as a stop layer during said patterning said heating element and said thermally conductive and electrically insulating material.

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

9. The method of claim 1, further comprising:

etching said phase-change material;

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

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

providing a heat spreader;

depositing a middle dielectric over said heat spreader;

depositing a heating element over said middle dielectric;

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

patterning said heating element and said thermally conductive and electrically insulating material;

depositing a layer of an upper dielectric;

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

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

12. 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.

13. 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.

14. The method of claim 10, wherein said heat spreader performs as a stop layer during said patterning said heating element and said thermally conductive and electrically insulating material.

15. 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.

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

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

providing a heat spreader;

depositing a heating element;

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

patterning said heating element and said thermally conductive and electrically insulating material, wherein said thermally conductive and electrically insulating material is self-aligned with said heating element;

depositing a layer of an upper dielectric;

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

18. The method of claim 17, 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.

19. The method of claim 17, 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.

20. The method of claim 17, further comprising depositing a contact uniformity support layer over said phase-change material.