Semiconductor device

• US 8,866,233 B2
• Filed: 01/03/2011
• Issued: 10/21/2014
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Rizkallah, Kimberly
• Assistant Examiner(s): Ligai, Maria
• Application Number:
  US12/983,578
• Publication Number:
  US 20110175104A1
• Time in Patent Office: 1,387 Days
• Field of Search: 257/59, 257/72, 257/103, 257/187, 257/444, 257/300, 257/306, 257/368, 257/379, 257/E27.013, 257/E27.014, 257/E27.016, 257/E27.017, 257/E29.116, 257/E29.117, 257/E29.151, 257/E51.006, 438/152, 438/241, 438/250, 349/46, 349/47, 349/43, 349/48
• US Class Current: 257/379
• CPC Class Codes: H01L 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• 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 27/1229 with different crystal properties within a device or between different devices

Abstract

An object is to provide a semiconductor device having a novel structure which includes a combination of semiconductor elements with different characteristics and is capable of realizing higher integration. A semiconductor device includes a first transistor, which includes a first channel formation region including a first semiconductor material, and a first gate electrode, and a second transistor, which includes one of a second source electrode and a second drain electrode combined with the first gate electrode, and a second channel formation region including a second semiconductor material and electrically connected to the second source electrode and the second drain electrode.

Claims

1. A semiconductor device comprising:

a first transistor comprising;

a channel region including a first semiconductor material;

impurity regions between which the channel region is sandwiched;

a first gate insulating layer over the channel region;

a conductive layer including a first gate electrode over the first gate insulating layer; and

a first source electrode and a first drain electrode electrically connected to the impurity regions;

a second transistor comprising;

a second source electrode and a second drain electrode wherein the conductive layer includes one of the second source electrode and the second drain electrode and wherein the other of the second source electrode and the second drain electrode is separated from the first gate electrode;

a semiconductor layer including a second semiconductor material and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the semiconductor layer; and

a second gate electrode over the second gate insulating layer; and

an insulating layer in direct contact with the impurity regions and the semiconductor layer.

2. The semiconductor device according to claim 1, wherein the first semiconductor material is different from the second semiconductor material.

3. The semiconductor device according to claim 1, wherein the second semiconductor material comprises an oxide semiconductor material.

4. The semiconductor device according to claim 1, wherein the second semiconductor material has an energy gap of more than 3 eV.

5. The semiconductor device according to claim 1, wherein a switching speed of the first transistor is higher than a switching speed of the second transistor.

6. The semiconductor device according to claim 1, wherein an off-state current of the second transistor is smaller than an off-state current of the first transistor.

7. The semiconductor device according to claim 1, wherein the semiconductor device is incorporated into one selected from the group consisting of a personal computer, a portable information terminal, an electronic book, a mobile phone, a digital video camera, and a television set.

8. The semiconductor device according to claim 1, wherein the conductive layer is a single layer.

9. A semiconductor device comprising:

a first transistor comprising;

a channel region including a first semiconductor material;

impurity regions between which the channel region is sandwiched;

a first gate insulating layer over the channel region;

a conductive layer including a first gate electrode over the first gate insulating layer; and

a first source electrode and a first drain electrode electrically connected to the impurity regions;

a second transistor comprising;

a second source electrode and a second drain electrode wherein the conductive layer includes one of the second source electrode and the second drain electrode and wherein the other of the second source electrode and the second drain electrode is separated from the first gate electrode;

a semiconductor layer including a second semiconductor material and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the semiconductor layer; and

a second gate electrode over the second gate insulating layer;

a capacitor comprising;

one of the second source electrode and the second drain electrode;

the second gate insulating layer; and

a capacitor electrode over the second gate insulating layer; and

an insulating layer in direct contact with the impurity regions and the semiconductor layer.

10. The semiconductor device according to claim 9, wherein the first semiconductor material is different from the second semiconductor material.

11. The semiconductor device according to claim 9, wherein the second semiconductor material comprises an oxide semiconductor material.

12. The semiconductor device according to claim 9, wherein the second semiconductor material has an energy gap of more than 3 eV.

13. The semiconductor device according to claim 9, wherein a switching speed of the first transistor is higher than a switching speed of the second transistor.

14. The semiconductor device according to claim 9, wherein an off-state current of the second transistor is smaller than an off-state current of the first transistor.

15. The semiconductor device according to claim 9, wherein the semiconductor device is incorporated into one selected from the group consisting of a personal computer, a portable information terminal, an electronic book, a mobile phone, a digital video camera, and a television set.

16. The semiconductor device according to claim 9, wherein the conductive layer is a single layer.

17. A semiconductor device comprising:

a first transistor comprising;

a channel region including a first semiconductor material;

impurity regions between which the channel region is sandwiched;

a first gate insulating layer over the channel region;

a conductive layer including a first gate electrode over the first gate insulating layer; and

a first source electrode and a first drain electrode electrically connected to the impurity regions;

a second transistor comprising;

a second source electrode and a second drain electrode wherein the conductive layer includes one of the second source electrode and the second drain electrode and wherein the other of the second source electrode and the second drain electrode is separated from the first gate electrode;

a semiconductor layer including a second semiconductor material and electrically connected to the second source electrode and the second drain electrode;

a second gate insulating layer over the semiconductor layer; and

a second gate electrode over the second gate insulating layer; and

an insulating layer in direct contact with the impurity regions and the semiconductor layer, wherein each of the first transistor and the second transistor is a top gate transistor, and wherein the insulating layer is configured to surround the first transistor.

18. The semiconductor device according to claim 17, wherein the first semiconductor material is different from the second semiconductor material.

19. The semiconductor device according to claim 17, wherein the second semiconductor material comprises an oxide semiconductor material.

20. The semiconductor device according to claim 17, wherein the second semiconductor material has an energy gap of more than 3 eV.

21. The semiconductor device according to claim 17, wherein a switching speed of the first transistor is higher than a switching speed of the second transistor.

22. The semiconductor device according to claim 17, wherein an off-state current of the second transistor is smaller than an off-state current of the first transistor.

23. The semiconductor device according to claim 17, wherein the semiconductor device is incorporated into one selected from the group consisting of a personal computer, a portable information terminal, an electronic book, a mobile phone, a digital video camera, and a television set.

24. The semiconductor device according to claim 17, wherein the conductive layer is a single layer.