METHOD TO MAKE RF-PCM SWITCHES AND CIRCUITS WITH PHASE-CHANGE MATERIALS

• US 20140191181A1
• Filed: 01/09/2013
• Published: 07/10/2014
• Est. Priority Date: 01/09/2013
• Status: Active Grant

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: Moon, Jeung-Sun
• Granted Patent: US 8,900,930 B2
• Time in Patent Office: Days
• US Class Current: 257/4
• CPC Class Codes: H01P 1/15 by semiconductor devices
• CPC Class Codes: H01P 3/00 Waveguides; Transmission lines of the waveguide type
• CPC Class Codes: H10B 63/20 comprising selection components having two electrodes, e.g. diodes
• CPC Class Codes: H10B 63/80 Arrangements comprising multiple bistable or multi-stable switching components of the same type on a plane parallel to the substrate, e.g. cross-point arrays
• CPC Class Codes: H10N 70/011 Manufacture or treatment of multistable switching devices
• 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 70/253 having three or more electrodes, e.g. transistor-like devices
• CPC Class Codes: H10N 70/826 adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/841 Electrodes
• CPC Class Codes: H10N 70/8828 Tellurides, e.g. GeSbTe
• CPC Class Codes: H10N 79/00 Integrated devices, or assemblies of multiple devices, comprising at least one solid-state element covered by group H10N70/00 ReRAM devices H10B63/00; PCRAM devices H10B63/10

Abstract

A radio frequency switch includes a first transmission line, a second transmission line, a first electrode electrically coupled to the first transmission line, a second electrode electrically coupled to the second transmission line, and a phase change material, the first transmission line coupled to a first area of the phase change material and the second transmission line coupled to a second area of the phase change material. When a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes state from a high resistance state to a low resistance state allowing transmission from the first transmission line to the second transmission line. The radio frequency switch is integrated on a substrate.

Claims

1. A radio frequency switch comprising:

a first transmission line;

a second transmission line;

a first electrode electrically coupled to the first transmission line;

a second electrode electrically coupled to the second transmission line; and

a phase change material, the first transmission line coupled to a first area of the phase change material and the second transmission line coupled to a second area of the phase change material;

wherein when a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes state from a high resistance state to a low resistance state allowing transmission from the first transmission line to the second transmission line; and

wherein the radio frequency switch is integrated on a substrate.

2. The radio frequency switch of claim 1 further comprising:

a first conductor connected to the phase change material and connected to the first transmission line, the first conductor being between the phase change material and the first transmission line; and

a second conductor connected to the phase change material and connected to the second transmission line, the second conductor being between the phase change material and the second transmission line;

wherein the first and second conductors comprise titanium nitride (TiN), tungsten (W), or any metal that does not form an alloy with the phase change material.

3. The radio frequency switch of claim 1 further comprising:

wherein the second transmission line is formed on the substrate; and

an insulator formed on the substrate and between the first transmission line and the second transmission line to reduce parasitic capacitive coupling between the first and second transmission lines;

wherein the substrate comprises silicon (Si), silicon germanium (SiGe), silicon carbide (SiC), sapphire, pyrex, gallium arsenide (GaAs), GaN, InAs, InSb, InP or any other III-V material; and

wherein the insulator comprises silicon dioxide (SiO₂), silicon nitride (Si₃N₄), benzo-cyclo-butene (BCB), or any low-k dielectric insulator.

4. The radio frequency switch of claim 1 further comprising:

a first capacitor coupled in series to the first transmission line for preventing current and voltage on the first electrode from transmitting on the first transmission line; and

a second capacitor coupled in series to the second transmission line for preventing current and voltage on the second electrode from transmitting on the second transmission line.

5. The radio frequency switch of claim 1 further comprising:

a first inductor coupled in series to the first electrode for preventing a radio frequency signal on the first transmission line from transmitting on the first electrode; and

a second inductor coupled in series to the second electrode for preventing a radio frequency signal on the second transmission line from transmitting on the second electrode.

6. The radio frequency switch of claim 1 wherein when a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes from an amorphous high resistance material to a crystalline low resistance material.

7. The radio frequency switch of claim 1 wherein:

the phase change material comprises Ge_xTe_1-x, Ge_xSb_yTe_z, or derivatives of Ge_xTe_1-x or Ge_xSb_yTe_z.

8. The radio frequency switch of claim 1 wherein:

the first and second transmission lines are radio frequency transmission lines.

9. The radio frequency switch of claim 1 wherein the radio frequency switch is connected to external capacitors and inductors in a planar configuration or in a three dimensional configuration.

10. A radio frequency switch comprising:

a first transmission line;

a second transmission line;

a first electrode;

a second electrode; and

a phase change material;

the first transmission line coupled to a first area of the phase change material, the second transmission line coupled to a second area of the phase change material, the first electrode coupled to a third area of the phase change material, and the second electrode coupled to a fourth area of the phase change material;

wherein when a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes state from a high resistance state to a low resistance state allowing transmission from the first transmission line to the second transmission line; and

wherein the radio frequency switch is integrated on a substrate.

11. The radio frequency switch of claim 10 further comprising:

a first conductor connected to the third area of the phase change material and connected to the first electrode, the first conductor being between the phase change material and the first electrode; and

a second conductor connected to the fourth area of the phase change material and connected to the second electrode, the second conductor being between the phase change material and the second electrode;

wherein the first and second conductors comprise titanium nitride (TiN), tungsten (W), or any metal that does not form an alloy with the phase change material.

12. The radio frequency switch of claim 10 further comprising:

wherein the second electrode is formed on the substrate; and

an insulator formed on the substrate and between the substrate and the first and second transmission lines to reduce parasitic capacitive coupling between the first and second transmission lines;

wherein the substrate comprises silicon (Si), silicon germanium (SiGe), silicon carbide (SiC), sapphire, pyrex, gallium arsenide (GaAs), GaN, InAs, InSb, InP or any other III-V material; and

wherein the insulator comprises silicon dioxide (SiO₂), silicon nitride (Si₃N₄), benzo-cyclo-butene (BCB), or any low-k dielectric insulator.

13. The radio frequency switch of claim 10 further comprising:

a first capacitor coupled in series to the first transmission line for preventing current and voltage on the first electrode from transmitting on the first transmission line; and

a second capacitor coupled in series to the second transmission line for preventing current and voltage on the second electrode from transmitting on the second transmission line.

14. The radio frequency switch of claim 10 further comprising:

a first inductor coupled in series to the first electrode for preventing a radio frequency signal on the first transmission line from transmitting on the first electrode; and

a second inductor coupled in series to the second electrode for preventing a radio frequency signal on the second transmission line from transmitting on the second electrode.

15. The radio frequency switch of claim 10 wherein:

the phase change material comprises Ge_xTe_1-x, Ge_xSb_yTe_z, or derivatives of Ge_xTe_1-x or Ge_xSb_yTe_z.

16. The radio frequency switch of claim 10 wherein:

the first and second transmission lines are radio frequency transmission lines.

17. The radio frequency switch of claim 10 wherein the radio frequency switch is connected to external capacitors and inductors in a planar configuration or in a three dimensional configuration.

18. A method of making a radio frequency switch comprising:

forming an insulator on a substrate;

forming a first transmission line on the insulator and coupled to a first area of a phase change material;

forming a second transmission line on the insulator and coupled to a second area of the phase change material;

forming a first conductor connected to a third area of the phase change material;

forming a first electrode connected to the first conductor;

forming a second conductor connected to a fourth area of the phase change material; and

forming a second electrode connected to the second conductor.

19. The method of claim 18 wherein:

the substrate comprises silicon (Si), silicon germanium (SiGe), silicon carbide (SiC), sapphire, pyrex, gallium arsenide (GaAs), GaN, InAs, InSb, InP or any other III-V material;

the insulator comprises silicon dioxide (SiO₂), silicon nitride (Si₃N₄), benzo-cyclo-butene (BCB), or any low-k dielectric insulator;

the first and second conductors comprise titanium nitride (TiN), tungsten (W), or any metal that does not form an alloy with the phase change material; and

the phase change material comprises Ge_xTe_1-x, Ge_xSb_yTe_z, or derivatives of Ge_xTe_1-x or Ge_xSb_yTe_z.

20. The method of claim 18 wherein:

the first and second transmission lines are radio frequency transmission lines.

21. A reconfigurable circuit comprising;

a first circuit comprising at least a first radio frequency switch integrated with circuitry comprising GaN based transistors or III-IV bipolar transistors;

the first radio frequency switch comprising;

a first transmission line;

a second transmission line;

a first electrode;

a second electrode; and

a phase change material;

wherein the first transmission line coupled to a first area of the phase change material, the second transmission line coupled to a second area of the phase change material, the first electrode coupled to a third area of the phase change material, and the second electrode coupled to a fourth area of the phase change material; and

wherein when a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes state from a high resistance state to a low resistance state allowing transmission from the first transmission line to the second transmission line.

22. The reconfigurable circuit of claim 21 comprising;

a second circuit comprising at least a second radio frequency switch integrated with circuitry comprising GaN based transistors or III-IV bipolar transistors;

the second radio frequency switch comprising;

a first transmission line;

a second transmission line;

a first electrode;

a second electrode; and

a phase change material;

wherein the first transmission line coupled to a first area of the phase change material, the second transmission line coupled to a second area of the phase change material, the first electrode coupled to a third area of the phase change material, and the second electrode coupled to a fourth area of the phase change material;

wherein when a direct current is sent from the first electrode to the second electrode through the phase change material, the phase change material changes state from a high resistance state to a low resistance state allowing transmission from the first transmission line to the second transmission line; and

at least one conductor connected between the first circuit and the second circuit.

23. The reconfigurable circuit of claim 22 wherein the first circuit is stacked on top of the second circuit to form a three dimensional circuit.

24. The compact reconfigurable circuit of claim 21 wherein the conductors are metal vias.