IP Library Granted Patent US 9,779,812
Granted Patent B1
US 9,779,812 · App. 15/269,523 · Granted Oct 3, 2017

Semiconductor memory device

Inventors: Kunifumi Suzuki (Mie, JP); Kazuhiko Yamamoto (Mie, JP)
Assignee: TOSHIBA MEMORY CORPORATION
G11C13/0069G11C13/0064
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Quick Facts
Patent No.
US 9,779,812
App. No.
15/269,523
Granted
Oct 3, 2017
Kind
B1
Abstract

According to one embodiment, a semiconductor memory device includes a first electrode, a second electrode, a memory cell, and a control circuit. The memory cell is provided between the first electrode and the second electrode, and includes a metal film and a resistance change film. The control circuit applies a voltage between the first electrode and the second electrode to transition a resistive state of the memory cell. The control circuit performs a first reset operation by applying a first pulse having a voltage of a first polarity to the memory cell, and applying a second pulse having a voltage of a second polarity that is an inverse of the first polarity to the memory cell after applying the first pulse.

Claims (62)

1. A semiconductor memory device, comprising:

a first electrode;

a second electrode;

a memory cell provided between the first electrode and the second electrode, the memory cell including a metal containing film and a resistance change film; and

a control circuit that applies a voltage between the first electrode and the second electrode to perform transition of a resistive state of the memory cell, wherein

the control circuit performs a first reset operation, a verify operation and a second reset operation,

the first reset operation is performed by applying a first pulse having a voltage of a first polarity to the memory cell, and applying a second pulse having a voltage of a second polarity that is an inverse of the first polarity to the memory cell after applying the first pulse,

the verify operation confirms whether the memory cell is in a desired state, performed by applying the memory cell with a verify pulse having the first polarity,

the second reset operation is performed by applying a sixth pulse having a larger voltage than a voltage of the second pulse and a second polarity, and

the control circuit performs the verify operation every time the first reset operation terminates and performs the second reset operation when the memory cell is out of a desired state after performing the verify operation.

2. The semiconductor memory device according to claim 1 , wherein:

the control circuit performs a set operation by applying a third pulse having a voltage of the first polarity to the memory cell when transitioning the memory cell to a low resistance state; and

the voltage of the first pulse has a lower value than the voltage of the third pulse.

3. The semiconductor memory device according to claim 2 , wherein

the voltage of the first pulse has a magnitude of equal to or more than 30% and equal to or less than 80% of the voltage of the third pulse.

4. The semiconductor memory device according to claim 1 , wherein:

the control circuit applies a further pulse having a voltage of the first polarity to the memory cell when transitioning the memory cell to the low resistance state; and

the voltage of the first pulse has a magnitude of equal to or more than 80% of the voltage of the further pulse.

5. The semiconductor memory device according to claim 1 , wherein

a product of an amplitude and a pulse width of the first pulse is smaller than a product of an amplitude and a pulse width of the second pulse.

6. The semiconductor memory device according to claim 1 , wherein

the control circuit starts to apply the second pulse within 100 nsec since termination of applying the first pulse.

7. The semiconductor memory device according to claim 1 , wherein:

the resistance change film is provided between the first electrode and the second electrode; and

the metal containing film is provided between the resistance change film and the second electrode.

8. The semiconductor memory device according to claim 1 , wherein

the control circuit, when transitioning the memory cell to a high resistance state,

applies a positive first voltage to the second electrode, and

applies a second voltage lower than the first voltage to the second electrode after applying the first voltage.

9. The semiconductor memory device according to claim 8 , wherein

the control circuit

applies a negative third voltage to the first electrode before starting to apply the first voltage,

increases the voltage of the first electrode to a positive fourth voltage from the third voltage before starting to apply the second voltage after termination of applying the first voltage, and

terminates applying the fourth voltage after termination of applying the second voltage.

10. A semiconductor memory device, comprising:

a first wiring;

a second wiring intersecting with the first wiring;

a memory cell provided between the first wiring and the second wiring, the memory cell including a metal containing film and a resistance change film; and

a control circuit that applies any voltage to the first wiring and the second wiring, wherein

the control circuit, when transitioning the memory cell to a high resistance state, between the first wiring and the second wiring,

applies a first pulse having a voltage of a first polarity and

applies a second pulse having a voltage of a second polarity that is an inverse of the first polarity after applying the first pulse,

the first pulse is applied by:

applying a negative third voltage to the second wiring; and

applying a positive first voltage to the first wiring while the third voltage is applied, and

the second pulse is applied by:

increasing the voltage of the second wiring to a positive fourth voltage from the third voltage after termination of applying the first voltage;

applying a second voltage lower than the first voltage to the first wiring after increasing the voltage of the second wiring to the fourth voltage; and

terminating applying the fourth voltage after termination of applying the second voltage.

11. The semiconductor memory device according to claim 10 , wherein:

the control circuit applies a third pulse having a voltage of the first polarity between the first wiring and the second wiring when transitioning the memory cell to a low resistance state; and

the voltage of the first pulse has a magnitude of equal to or more than 30% of the voltage of the third pulse.

12. The semiconductor memory device according to claim 10 , wherein:

the control circuit applies a further pulse having the voltage of the first polarity between the first wiring and the second wiring when transitioning the memory cell to the low resistance state; and

the voltage of the first pulse has a magnitude of equal to or more than 80% of the voltage of the further pulse.

13. The semiconductor memory device according to claim 10 , wherein

a product of an amplitude and a pulse width of the first pulse is smaller than a product of an amplitude and a pulse width of the second pulse.

14. The semiconductor memory device according to claim 10 , wherein

the control circuit starts to apply the second pulse within 100 nsec since termination of applying the first pulse.

15. The semiconductor memory device according to claim 10 , wherein:

the resistance change film is provided between the first wiring and the second wiring; and

the metal containing film is provided between the resistance change film and the first wiring.

Assignments (5)
MERGER Recorded Jan 22, 2021
From: TOSHIBA MEMORY CORPORATION
To: K.K. PANGEA
Reel/Frame 055659/0471 →
CHANGE OF NAME AND ADDRESS Recorded Jan 22, 2021
From: TOSHIBA MEMORY CORPORATION
To: KIOXIA CORPORATION
Reel/Frame 055669/0001 →
CHANGE OF NAME AND ADDRESS Recorded Jan 22, 2021
From: K.K. PANGEA
To: TOSHIBA MEMORY CORPORATION
Reel/Frame 055669/0401 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 21, 2017
From: KABUSHIKI KAISHA TOSHIBA
To: TOSHIBA MEMORY CORPORATION
Reel/Frame 043063/0178 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 19, 2016
From: SUZUKI, KUNIFUMI; YAMAMOTO, KAZUHIKO
To: KABUSHIKI KAISHA TOSHIBA
Reel/Frame 039783/0846 →
Continuity (1)
Provisional Application 62309684 · Mar 17, 2016