Phase-change material (PCM) RF switch having contacts to PCM and heating element

Patent metadata

Field	Value
Publication number	US-10833260-B2
Application number	US-201916709823-A
Country	US
Kind code	B2
Filing date	Dec 10, 2019
Priority date	Aug 14, 2018
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

In fabricating a radio frequency (RF) switch, a phase-change material (PCM) and a heating element, underlying an active segment of the PCM and extending outward and transverse to the PCM, are provided. Lower portions of PCM contacts for connection to passive segments of the PCM are formed, wherein the passive segments extend outward and are transverse to the heating element. Upper portions of the PCM contacts are formed from a lower interconnect metal. Heating element contacts are formed cross-wise to the PCM contacts. The heating element contacts can comprise a top interconnect metal directly connecting with terminal segments of the heating element. The heating element contacts can comprise a top interconnect metal and intermediate metal segments for connecting with the terminal segments of the heating element.

First claim

The invention claimed is:

1. A radio frequency (RF) switch comprising:
a phase-change material (PCM) and a heating element approximately underlying an active segment of said PCM and extending outward and transverse to said PCM;
PCM contacts comprising lower portions and upper portions;
said lower portions of said PCM contacts connected to passive segments of said PCM, wherein said passive segments extend outward and are transverse to said heating element;
said upper portions of said PCM contacts made from a lower interconnect metal, wherein said upper portions of said PCM contacts have an offset away from said active segment of said PCM;
heating element contacts comprising a top interconnect metal and intermediate metal segments for connecting with terminal segments of said heating element;
said heating element contacts being situated cross-wise to said PCM contacts so as to reduce a C OFF of said PCM.

2. The radio frequency (RF) switch of claim 1 , further comprising a contact uniformity support layer over said PCM.

3. The radio frequency (RF) switch of claim 1 , further including a nugget comprising a thermally conductive and electrically insulating material situated on top of said heating element.

4. The radio frequency (RF) switch of claim 3 , wherein said thermally conductive and electrically insulating material is selected from the group consisting of AlN, Al X O Y , Be X O Y , SiC, Si X N Y , diamond, and diamond-like carbon.

5. The radio frequency (RF) switch of claim 1 , wherein said lower portions of said PCM contacts are formed from said lower interconnect metal.

6. The radio frequency (RF) switch of claim 1 , wherein said lower portions of said PCM contacts are planarized with a contact dielectric.

7. The radio frequency (RF) switch of claim 1 , wherein said PCM comprises a material selected from the group consisting of germanium telluride (Ge X Te Y ), germanium antimony telluride (Ge X Sb Y Te Z ), germanium selenide (Ge X Se Y ), and any other chalcogenide.

8. A radio frequency (RF) switch comprising:
a phase-change material (PCM) and a heating element approximately underlying an active segment of said PCM;
a PCM contact comprising a lower portion and an upper portion;
said lower portion of said PCM contact connected to a passive segment of said PCM;
said upper portion of said PCM contact having an offset away from said active segment of said PCM;
a heating element contact comprising a top interconnect metal and intermediate metal segments for connecting with a terminal segment of said heating element.

9. The radio frequency (RF) switch of claim 8 , wherein said upper portion of said PCM contact is made from a lower interconnect metal.

10. The radio frequency (RF) switch of claim 9 , wherein said lower portion of said PCM contact is formed from said lower interconnect metal.

11. The radio frequency (RF) switch of claim 8 , wherein said lower portion of said PCM contact is planarized with a contact dielectric.

12. The radio frequency (RF) switch of claim 8 further comprising a contact uniformity support layer over said PCM.

13. The radio frequency (RF) switch of claim 8 further including a nugget comprising a thermally conductive and electrically insulating material situated on top of said heating element.

14. The radio frequency (RF) switch of claim 13 , wherein said thermally conductive and electrically insulating material is selected from the group consisting of AlN, Al X O Y , Be X O Y , SiC, Si X N Y , diamond, and diamond-like carbon.

15. The radio frequency (RF) switch of claim 8 , wherein said PCM comprises a material selected from the group consisting of germanium telluride (Ge X Te Y ), germanium antimony telluride (Ge X Sb Y Te Z ), germanium selenide (Ge X Se Y ), and any other chalcogenide.

16. A radio frequency (RF) switch comprising:
a phase-change material (PCM) and a heating element approximately underlying an active segment of said PCM and extending outward and transverse to said PCM;
a thermally conductive and electrically insulating material situated over said heating element;
PCM contacts comprising lower portions and upper portions;
said lower portions of said PCM contacts connected to passive segments of said PCM, wherein said passive segments extend outward and are transverse to said heating element;
said upper portions of said PCM contacts made from a lower interconnect metal wherein said upper portions of said PCM contacts have an offset away from said active segment of said PCM;
heating element contacts comprising a top interconnect metal and intermediate metal segments for connecting with terminal segments of said heating element.

17. The radio frequency (RF) switch of claim 16 further comprising a contact uniformity support layer over said PCM.

18. The radio frequency (RF) switch of claim 16 , wherein said thermally conductive and electrically insulating material is selected from the group consisting of AlN, Al X O Y , Be X O Y , SiC, Si X N Y , diamond, and diamond-like carbon.

19. The radio frequency (RF) switch of claim 16 , wherein said PCM comprises a material selected from the group consisting of germanium telluride (Ge X Te Y ), germanium antimony telluride (Ge X Sb Y Te Z ), germanium selenide (Ge X Se Y ), and any other chalcogenide.

20. The radio frequency (RF) switch of claim 16 , wherein said thermally conductive and electrically insulating material is selected from the group consisting of AlN, Al X O Y , Be X O Y , SiC, Si X N Y , diamond, and diamond-like carbon, and wherein said PCM comprises a material selected from the group consisting of germanium telluride (Ge X Te Y ), germanium antimony telluride (Ge X Sb Y Te Z ), germanium selenide (Ge X Se Y ), and any other chalcogenide.

Assignees

• Newport Fab Llc

Inventors

• Rose Jefferson E
• Slovin Gregory P
• Howard David J
• Debar Michael J
• El-Hinnawy Nabil

Classifications

• H10P14/40

  of conductive or resistive materials · CPC title

• H10W44/20

  at high-frequency [HF] or radio frequency [RF] · CPC title

• H10W20/084

  for dual-damascene structures · CPC title

• H10W20/081

  by forming openings in the dielectric parts · CPC title

• H10W20/063

  by forming conductive members before forming protective insulating material · CPC title