SEMICONDUCTOR DEVICE

• US 20110176354A1
• Filed: 01/10/2011
• Published: 07/21/2011
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kato, Kiyoshi, Koyama, Jun, Yamazaki, Shunpei
• Granted Patent: US 8,339,836 B2
• Time in Patent Office: Days
• US Class Current: 365/149
• CPC Class Codes: G11C 11/403 with charge regeneration common to a multiplicity of memory cells, i.e. external refresh
• CPC Class Codes: G11C 11/405 with three charge-transfer gates, e.g. MOS transistors, per cell
• CPC Class Codes: G11C 16/02 electrically programmable
• CPC Class Codes: G11C 5/063 Voltage and signal distribution in integrated semi-conductor memory access lines, e.g. word-line, bit-line, cross-over resistance, propagation delay
• CPC Class Codes: H01L 27/1207 combined with devices in contact with the semiconductor body, i.e. bulk/SOI hybrid circuits
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 28/60 Electrodes
• CPC Class Codes: H10B 12/30 DRAM devices comprising one-transistor - one-capacitor [1T-1C] memory cells
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10B 41/70 the floating gate being an electrode shared by two or more components

Abstract

An object is to provide a semiconductor device with a novel structure in which stored data can be retained even when power is not supplied, and does not have a limitation on the number of times of writing operations. A semiconductor device includes a source-bit line, a first signal line, a second signal line, a word line, and a memory cell connected between the source-bit lines. The memory cell includes a first transistor, a second transistor, and a capacitor. The second transistor is formed including an oxide semiconductor material. A gate electrode of the first transistor, one of a source and drain electrodes, and one of electrodes of the capacitor are electrically connected to one another. The source-bit line and a source electrode of the first transistor are electrically connected to each other. Another source-bit line adjacent to the above source-bit line and a drain electrode of the first transistor are electrically connected to each other.

Claims

1. A semiconductor device comprising:

a plurality of source-bit lines extended in a first direction;

a plurality of first signal lines extended in the first direction;

a plurality of second signal lines extended in a second direction;

a plurality of word lines extended in the second direction;

a plurality of memory cells connected in parallel between the plurality of source-bit lines;

a first driver circuit electrically connected to the plurality of source-bit lines;

a second driver circuit electrically connected to the plurality of first signal lines;

a third driver circuit electrically connected to the plurality of second signal lines; and

a fourth driver circuit electrically connected to the plurality of word lines,

wherein one of the plurality of memory cells comprises;

a first transistor comprising a first gate electrode, a first source electrode, and a first drain electrode;

a second transistor comprising a second gate electrode, a second source electrode, and a second drain electrode; and

a capacitor,

wherein the second transistor includes an oxide semiconductor material,

wherein the first gate electrode, one of the second source and drain electrodes, and one of electrodes of the capacitor are electrically connected to one another,

wherein one of the plurality of source-bit lines and the first source electrode are electrically connected to each other,

wherein another of the plurality of source-bit lines adjacent to the one of the plurality of source-bit lines and the first drain electrode are electrically connected to each other,

wherein one of the plurality of first signal lines and the other of the second source and drain electrodes are electrically connected to each other,

wherein one of the plurality of second signal lines and the second gate electrode are electrically connected to each other, and

wherein one of the plurality of word lines and the other of the electrodes of the capacitor are electrically connected to each other.

2. The semiconductor device according to claim 1, wherein the first transistor includes single crystal silicon.

3. The semiconductor device according to claim 1, wherein the first transistor comprises:

a first channel formation region including a semiconductor material other than an oxide semiconductor;

impurity regions adjacent to the first channel formation region;

a first gate insulating layer over the first channel formation region;

the first gate electrode over the first gate insulating layer; and

the first source electrode and the first drain electrode electrically connected to the impurity regions.

4. The semiconductor device according to claim 1, wherein the second transistor comprises:

the second source electrode and the second drain electrode over the first transistor;

a second channel formation region including the oxide semiconductor material, and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the second channel formation region; and

the second gate electrode over the second gate insulating layer.

5. The semiconductor device according to claim 1, wherein the capacitor comprises:

the second source electrode or the second drain electrode;

an oxide semiconductor layer including the oxide semiconductor material;

the second gate insulating layer; and

a capacitor electrode over the second gate insulating layer.

6. The semiconductor device according to claim 1, wherein the semiconductor device is incorporated in one selected from the group consisting of a laptop computer, a portable information terminal, an e-book reader, a mobile phone, a digital camera, and a television device.

7. A semiconductor device comprising:

(n+1) (n is a natural number) source-bit lines extended in a first direction;

n first signal lines extended in the first direction;

m (m is a natural number) second signal lines extended in a second direction;

m word lines extended in the second direction;

(m×

n) memory cells connected in parallel between the source-bit lines;

a first driver circuit electrically connected to the source-bit lines;

a second driver circuit electrically connected to the first signal lines;

a third driver circuit electrically connected to the second signal lines; and

a fourth driver circuit electrically connected to the word lines,

wherein one of the memory cells comprises;

a first transistor comprising a first gate electrode, a first source electrode, and a first drain electrode;

a second transistor comprising a second gate electrode, a second source electrode, and a second drain electrode; and

a capacitor,

wherein the second transistor includes an oxide semiconductor material,

wherein the first gate electrode, one of the second source and drain electrodes, and one of electrodes of the capacitor are electrically connected to one another,

wherein one of the source-bit lines and the first source electrode are electrically connected to each other,

wherein another of the source-bit lines adjacent to the one of source-bit lines and the first drain electrode are electrically connected to each other,

wherein one of the first signal lines and the other of the second source and drain electrodes are electrically connected to each other,

wherein one of the second signal lines and the second gate electrode are electrically connected to each other,

wherein one of the word lines and the other of the electrodes of the capacitor are electrically connected to each other, and

wherein the one of the source-bit lines is electrically connected to a first source electrode of a memory cell adjacent to the one of memory cells.

8. The semiconductor device according to claim 7, wherein the first transistor includes single crystal silicon.

9. The semiconductor device according to claim 7, wherein the first transistor comprises:

a first channel formation region including a semiconductor material other than an oxide semiconductor;

impurity regions adjacent to the first channel formation region;

a first gate insulating layer over the first channel formation region;

the first gate electrode over the first gate insulating layer; and

the first source electrode and the first drain electrode electrically connected to the impurity regions.

10. The semiconductor device according to claim 7, wherein the second transistor comprises:

the second source electrode and the second drain electrode over the first transistor;

a second channel formation region including the oxide semiconductor material, and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the second channel formation region; and

the second gate electrode over the second gate insulating layer.

11. The semiconductor device according to claim 7, wherein the capacitor comprises:

the second source electrode or the second drain electrode;

an oxide semiconductor layer including the oxide semiconductor material;

the second gate insulating layer; and

a capacitor electrode over the second gate insulating layer.

12. The semiconductor device according to claim 7, wherein the semiconductor device is incorporated in one selected from the group consisting of a laptop computer, a portable information terminal, an e-book reader, a mobile phone, a digital camera, and a television device.

13. A semiconductor device comprising:

a plurality of source-bit lines extended in a first direction;

a plurality of first signal lines extended in a second direction;

a plurality of second signal lines extended in the first direction;

a plurality of word lines extended in the second direction;

a plurality of memory cells connected in parallel between the plurality of source-bit lines;

a first driver circuit electrically connected to the plurality of source-bit lines;

a second driver circuit electrically connected to the plurality of first signal lines;

a third driver circuit electrically connected to the plurality of second signal lines; and

a fourth driver circuit electrically connected to the plurality of word lines,

wherein one of the memory cells comprises;

a first transistor comprising a first gate electrode, a first source electrode, and a first drain electrode;

a second transistor comprising a second gate electrode, a second source electrode, and a second drain electrode; and

a capacitor,

wherein the second transistor includes an oxide semiconductor material,

wherein the first gate electrode, one of the second source and drain electrodes, and one of electrodes of the capacitor are electrically connected to one another,

wherein one of the plurality of source-bit lines and the first source electrode are electrically connected to each other,

wherein another of the plurality of source-bit lines adjacent to the one of the plurality of source-bit lines and the first drain electrode are electrically connected to each other,

wherein one of the plurality of first signal lines and the other of the second source and drain electrodes are electrically connected to each other,

wherein one of the plurality of second signal lines and the second gate electrode are electrically connected to each other, and

wherein one of the plurality of word lines and the other of the electrodes of the capacitor are electrically connected to each other.

14. The semiconductor device according to claim 13, wherein the first transistor includes single crystal silicon.

15. The semiconductor device according to claim 13, wherein the first transistor comprises:

a first channel formation region including a semiconductor material other than an oxide semiconductor;

impurity regions adjacent to the first channel formation region;

a first gate insulating layer over the first channel formation region;

the first gate electrode over the first gate insulating layer; and

the first source electrode and the first drain electrode electrically connected to the impurity regions.

16. The semiconductor device according to claim 13, wherein the second transistor comprises:

the second source electrode and the second drain electrode over the first transistor;

a second channel formation region including the oxide semiconductor material, and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the second channel formation region; and

the second gate electrode over the second gate insulating layer.

17. The semiconductor device according to claim 13, wherein the capacitor comprises:

the second source electrode or the second drain electrode;

an oxide semiconductor layer including the oxide semiconductor material;

the second gate insulating layer; and

a capacitor electrode over the second gate insulating layer.

18. The semiconductor device according to claim 13, wherein the semiconductor device is incorporated in one selected from the group consisting of a laptop computer, a portable information terminal, an e-book reader, a mobile phone, a digital camera, and a television device.

19. A semiconductor device comprising:

(n+1) (n is a natural number) source-bit lines extended in a first direction;

m (m is a natural number) first signal lines extended in a second direction;

n second signal lines extended in the first direction;

m word lines extended in the second direction;

(m×

n) memory cells connected in parallel between the source-bit lines;

a first driver circuit electrically connected to one of the source-bit lines;

a second driver circuit electrically connected to one of the first signal lines;

a third driver circuit electrically connected to one of the second signal lines; and

a fourth driver circuit electrically connected to one of the word lines;

wherein one of the memory cells comprises;

a first transistor comprising a first gate electrode, a first source electrode, and a first drain electrode;

a second transistor comprising a second gate electrode, a second source electrode, and a second drain electrode; and

a capacitor,

wherein the second transistor includes an oxide semiconductor material,

wherein the first gate electrode, one of the second source and drain electrodes, and one of electrodes of the capacitor are electrically connected to one another,

wherein one of the source-bit lines and the first source electrode are electrically connected to each other,

wherein another of the source-bit lines adjacent to the one of source-bit lines and the first drain electrode are electrically connected to each other,

wherein one of the first signal lines and the other of the second source and drain electrodes are electrically connected to each other,

wherein one of the second signal lines and the second gate electrode are electrically connected to each other,

wherein one of the word lines and the other of the electrodes of the capacitor are electrically connected to each other, and

wherein the one of source-bit lines is electrically connected to a first source electrode of a memory cell adjacent to the one of memory cells.

20. The semiconductor device according to claim 19, wherein the first transistor includes single crystal silicon.

21. The semiconductor device according to claim 19, wherein the first transistor comprises:

a first channel formation region including a semiconductor material other than an oxide semiconductor;

impurity regions adjacent to the first channel formation region;

a first gate insulating layer over the first channel formation region;

the first gate electrode over the first gate insulating layer; and

the first source electrode and the first drain electrode electrically connected to the impurity regions.

22. The semiconductor device according to claim 19, wherein the second transistor comprises:

the second source electrode and the second drain electrode over the first transistor;

a second channel formation region including the oxide semiconductor material, and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the second channel formation region; and

the second gate electrode over the second gate insulating layer.

23. The semiconductor device according to claim 19, wherein the capacitor comprises:

the second source electrode or the second drain electrode;

an oxide semiconductor layer including the oxide semiconductor material;

the second gate insulating layer; and

a capacitor electrode over the second gate insulating layer.

24. The semiconductor device according to claim 19, wherein the semiconductor device is incorporated in one selected from the group consisting of a laptop computer, a portable information terminal, an e-book reader, a mobile phone, a digital camera, and a television device.