MEMS switch

Abstract

A Micro Electro Mechanical System (MEMS) switch includes a substrate, a fixed signal line formed on the substrate, a movable signal line spaced apart from one of an upper surface and a lower surface of the fixed signal line, and at least one piezoelectric actuator connected to a first end of the movable signal line so as to bring or separate the movable signal line in contact with or from the fixed signal line. The piezoelectric actuator includes a first electrode, a piezoelectric layer formed on the first electrode, a second electrode formed on the piezoelectric layer, and a connecting layer formed on the second electrode and connected with the movable signal line.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above aspects and features of the present invention will be more apparent from the description for exemplary embodiments of the present invention taken with reference to the accompanying drawings, in which:

FIG. 1 is a top plan view exemplifying a structure of a conventional MEMS switch;

FIG. 2 is a cross-sectional view taken along line II-II′ of FIG. 1;

FIG. 3 is a perspective view exemplifying a structure of a MEMS switch in accordance with an exemplary embodiment of the present invention;

FIG. 4 is a cross-sectional view taken along line IV-IV′ of FIG. 3;

FIG. 5 is a perspective view exemplifying a structure of a MEMS switch in accordance with another exemplary embodiment of the present invention; and

FIG. 6 is a cross-sectional view taken along line VI-VI′ of FIG. 5.

Claims

1. A Micro Electro Mechanical System (MEMS) switch comprising: a substrate;a fixed signal line formed on the substrate;a movable signal line spaced apart from an upper surface of the fixed signal line; andat least one piezoelectric actuator connected to a first end of the movable signal line so as to bring or separate the movable signal line in contact with or from the fixed signal line.

2. The MEMS switch as claimed in claim 1, wherein the at least one piezoelectric actuator comprises: a first electrode;a piezoelectric layer formed on the first electrode;a second electrode formed on the piezoelectric layer; anda connecting layer formed on the second electrode and connected with the movable signal line.

3. The MEMS switch as claimed in claim 1, wherein the at least one piezoelectric actuator comprises a first end having a supporting part supported on the substrate, and a free end connected to the movable signal line.

4. The MEMS switch as claimed in claim 2, wherein the first and the second electrodes are formed of a material selected from Al, Au, Pt, W, Mo, Ta, Pt—Ta, Ti and Pt—Ti, respectively.

5. The MEMS switch as claimed in claim 2, wherein the piezoelectric layer is formed of a material selected from PZT, PLZT, ZnO, PMN, PMN-PT, PZN, PZN-PT and AlN.

6. The MEMS switch as claimed in claim 2, wherein the connecting layer is formed of a material selected from SiXNY and AlN.

7. The MEMS switch as claimed in claim 2, wherein the at least one piezoelectric actuator comprises two piezoelectric actuators arranged at opposite sides of the movable signal line.

8. The MEMS switch as claimed in claim 7, wherein connecting layers of the two piezoelectric actuators are connected in common with each other so as to interconnect the two piezoelectric actuators.

9. The MEMS switch as claimed in claim 2, wherein the movable signal line comprises a supporting part supported on the substrate.

10. A Micro Electro Mechanical System (MEMS) switch comprising: a substrate;a fixed signal line spaced apart from an upper surface of the substrate;a movable signal line spaced apart from the upper surface of the substrate and from a lower surface of the fixed signal line; andat least one piezoelectric actuator connected to a first end of the movable signal line so as to bring or separate the movable signal line in contact with or from the fixed signal line.

11. The MEMS switch as claimed in claim 10, wherein the at least one piezoelectric actuator comprises: a first electrode;a piezoelectric layer formed under the first electrode;a second electrode formed under the piezoelectric layer; anda connecting layer formed under the second electrode and connected with the movable signal line.

12. The MEMS switch as claimed in claim 10, wherein the at least one piezoelectric actuator comprises a first end having a supporting part supported on the substrate, and a free end connected to the movable signal line.

13. The MEMS switch as claimed in claim 11, wherein the first and the second electrodes are formed of a material selected from Al, Au, Pt, W, Mo, Ta, Pt—Ta, Ti and Pt—Ti, respectively.

14. The MEMS switch as claimed in claim 11, wherein the piezoelectric layer is formed of a material selected from PZT, PLZT, ZnO, PMN, PMN-PT, PZN, PZN-PT and AlN.

15. The MEMS switch as claimed in claim 11, wherein the connecting layer is formed of a material selected from SiXNY and AlN.

16. The MEMS switch as claimed in claim 11, wherein the at least one piezoelectric actuator comprises two piezoelectric actuators arranged at opposite sides of the movable signal line.

17. The MEMS switch as claimed in claim 16, wherein connecting layers of the two piezoelectric actuators are connected in common with each other so as to interconnect the two piezoelectric actuators.

18. The MEMS switch as claimed in claim 11, wherein the movable signal line comprises a supporting part supported on the substrate.

19. A Micro Electro Mechanical System (MEMS) switch comprising: a substrate;a fixed signal line formed on the substrate;a movable signal line spaced apart from one of an upper surface and a lower surface of the fixed signal line; andat least one piezoelectric actuator connected to a first end of the movable signal line so as to bring or separate the movable signal line in contact with or from the fixed signal line.