Switching element

• US 7,671,397 B2
• Filed: 09/20/2005
• Issued: 03/02/2010
• Est. Priority Date: 05/10/2005
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Fujita, Shinobu, Abe, Keiko
• Primary Examiner(s): Warren; Matthew E
• Application Number:
  US11/229,502
• Publication Number:
  US 20060255395A1
• Time in Patent Office: 1,624 Days
• Field of Search: 257/254, 257/315, 257/415, 257/E29.167, 257/E29.324, 257/E29.325, 361/277
• US Class Current: 257/315
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11C 13/025 using fullerenes, e.g. C60, or nanotubes, e.g. carbon or silicon nanotubes
• CPC Class Codes: G11C 23/00 Digital stores characterised by movement of mechanical parts to effect storage, e.g. using balls; Storage elements therefor
• CPC Class Codes: H01H 59/0009 making use of micromechanics

Abstract

There is disclosed a switching element including a first input/output electrode, a movable portion which repeats contact/non-contact with respect to the first input/output electrode, a second input/output electrode connected with the movable portion, a floating gate electrode which is coupled with the movable portion through an insulating layer and in which electric charge is stored, and a first gate electrode which generates an electrostatic force between itself and the floating gate electrode to control an operation of the movable portion.

Claims

1. A switching element comprising:

a first input/output electrode;

a movable portion which repeats contact/non-contact with respect to the first input/output electrode;

a second input/output electrode connected with the movable portion;

a floating gate electrode combined with the movable portion through an insulating layer and in which electric charge is stored; and

a first gate electrode which generates an electrostatic force between itself and the floating gate electrode to control an operation of the movable portion, the first gate electrode including first and second capacitor electrodes, both of the first and second capacitor electrodes being disposed on a same side of the movable portion as the floating gate electrode.

2. The switching element according to claim 1, wherein the movable portion does not come into contact with the first input/output electrode in a state where the electrostatic force is not generated.

3. The switching element according to claim 1, wherein the movable portion comes into contact with the first input/output electrode in a state where the electrostatic force is not generated.

4. The switching element according to claim 1, wherein the floating gate electrode is arranged on the movable portion.

5. The switching element according to claim 4, wherein the insulating layer has a function of provoking tunneling of the electric charge.

6. The switching element according to claim 4, further comprising a shield layer which is arranged between the floating gate electrode and the movable portion and shields against the electrostatic force.

7. The switching element according to claim 1, wherein the floating gate electrode and the movable portion are arranged in the same layer.

8. The switching element according to claim 7, further comprising an electrode for electric charge injection which is connected with the floating gate electrode through the insulating layer having the function of provoking tunneling of the electric charge.

9. The switching element according to claim 1, wherein a movable direction of the movable portion is a vertical direction with respect to a surface of a semiconductor substrate.

10. The switching element according to claim 1, wherein a movable direction of the movable portion is a horizontal direction with respect to a surface of a semiconductor substrate.

11. The switching element according to claim 1, further comprising a second gate electrode which is used with the first gate electrode as a pair to control the operation of the movable portion.

12. The switching element according to claim 1, wherein the movable portion is formed of carbon nanotubes or a material containing carbon.

13. The switching element according to claim 1, wherein the movable portion is of a doubly-supported beam type.

14. The switching element according to claim 1, wherein the movable portion is of a cantilever type.

15. An FES inverter comprising:

a first switch comprising a switching element according to claim 1; and

a second switch comprising a switching element according to claim 1,

wherein the first and second switches are connected in series.

16. The FES inverter according to claim 15, wherein threshold values of the first and second switches are different from each other.

17. An FES-AND comprising:

first and second switches which are connected in parallel between a ground terminal and an output terminal and each of which comprises a switching element according to claim 1; and

third and fourth switches which are connected in series between a power supply terminal and the output terminal and each of which comprises a switching element according to claim 1.

18. A semiconductor memory comprising:

a plurality of memory cell arrays and a plurality of peripheral circuits superimposed on a semiconductor substrate,

wherein each of the plurality of peripheral circuits has a switching element according to claim 1.

19. A system LSI comprising:

a plurality of circuit blocks superimposed on a semiconductor substrate,

wherein at least one of the plurality of circuit blocks has a switching element according to claim 1.

20. The system LSI according to claim 19, wherein the plurality of circuit blocks comprise:

a first circuit block having a main memory or a cache memory;

a second circuit block having a program memory or a virtual memory; and

an interface circuit arranged between the first and second circuit blocks, the interface circuit comprising the switching element.

21. The system LSI according to claim 20, wherein the interface circuit is a crossbar on-chip bus interface circuit in which the switching element is arranged at an intersection of wirings which are three-dimensionally arranged.

22. The system LSI according to claim 19, wherein the plurality of circuit blocks comprise:

a first circuit block having a processor; and

a second circuit block which is arranged on the first circuit block and has a cache memory comprising an SRAM, the cache memory comprising the switching element.

23. The system LSI according to claim 19, wherein the plurality of circuit blocks comprise:

a first circuit block having a first processor functioning as a CPU; and

a second circuit block which is arranged on the first circuit block and has a plurality of second processors functioning as signal processing circuits, the plurality of second processors comprising the switching elements.