Semiconductor device

• US 8,785,923 B2
• Filed: 04/17/2012
• Issued: 07/22/2014
• Est. Priority Date: 04/29/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Noda, Kosei
• Primary Examiner(s): Slutsker, Julia
• Application Number:
  US13/448,609
• Publication Number:
  US 20120273774A1
• Time in Patent Office: 826 Days
• Field of Search: 257/43, 257/330, 257/E21.41
• US Class Current: 257/43
• CPC Class Codes: H01L 21/823807 with a particular manufacturing method of the channel structures, e.g. channel implants, halo or pocket implants, or channel materials
• CPC Class Codes: H01L 21/8258 the substrate being a semiconductor, using a combination of technologies covered by H01L21/8206, H01L21/8213 , H01L21/822, H01L21/8252, H01L21/8254 or H01L21/8256
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 29/4236 within a trench, e.g. trench gate electrode, groove gate electrode
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/66621 using etching to form a recess at the gate location etching of semiconductor bodies H01L21/302
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

The semiconductor device includes transistors which are stacked. The transistors include a semiconductor substrate having a groove portion and a pair of low-resistance regions between which the groove portion is provided, a first gate insulating film over the semiconductor substrate, a gate electrode overlapping with the groove portion with the first gate insulating film interposed therebetween, a second gate insulating film covering the gate electrode, a pair of electrodes provided over the second gate insulating film so that the groove portion is sandwiched between the pair of electrodes, and a semiconductor film in contact with the pair of electrodes. One of the pair of low-resistance region is electrically connected to one of the pair of electrodes. One of the transistors includes an n-type semiconductor and the other includes a p-type semiconductor, so that a complementary MOS circuit is formed.

Claims

1. A semiconductor device comprising:

a first transistor and a second transistor overlapping with each other,

wherein the first transistor comprises;

a semiconductor substrate comprising a source region, a drain region and a groove portion between the source region and the drain region;

a first gate insulating film formed along a shape of the groove portion; and

a gate electrode formed in the groove portion with the first gate insulating film interposed therebetween,

wherein the second transistor comprises;

the gate electrode formed in the groove portion;

a second gate insulating film covering the gate electrode;

a semiconductor film overlapping with the gate electrode with the second gate insulating film interposed therebetween; and

a pair of electrodes formed in contact with the semiconductor film,

wherein each of the pair of electrodes is a metal layer, and

wherein one of the source region and the drain region is electrically connected to one of the pair of electrodes.

2. The semiconductor device according to claim 1, wherein the pair of electrodes is formed between the second gate insulating film and the semiconductor film.

3. The semiconductor device according to claim 1, wherein the semiconductor film is formed between the second gate insulating film and the pair of electrodes.

4. The semiconductor device according to claim 1, wherein the semiconductor substrate is an n-type semiconductor and the source region and the drain region are a p-type semiconductor.

5. The semiconductor device according to claim 1, wherein the semiconductor film comprises an oxide semiconductor comprising at least one of elements of In, Ga, Sn, and Zn.

11. The semiconductor device according to claim 1, wherein the metal layer contains at least one of aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver and tantalum.

6. A semiconductor device comprising:

a semiconductor substrate comprising a source region, a drain region and a groove portion between the source region and the drain region;

a first gate insulating film over the semiconductor substrate;

a gate electrode overlapping with the groove portion with the first gate insulating film interposed therebetween;

a second gate insulating film covering the gate electrode;

a pair of electrodes provided over the second gate insulating film so that the groove portion is sandwiched between the pair of electrodes; and

a semiconductor film which is in contact with the pair of electrodes and overlaps with the gate electrode with the second gate insulating film interposed therebetween,

wherein each of the pair of electrodes is a metal layer, and

wherein one of the source region and the drain region is electrically connected to one of the pair of electrodes.

7. The semiconductor device according to claim 6, wherein the pair of electrodes is formed between the second gate insulating film and the semiconductor film.

8. The semiconductor device according to claim 6, wherein the semiconductor film is formed between the second gate insulating film and the pair of electrodes.

9. The semiconductor device according to claim 6, wherein the semiconductor substrate is an n-type semiconductor and the source region and the drain region are a p-type semiconductor.

10. The semiconductor device according to claim 6, wherein the semiconductor film comprises an oxide semiconductor comprising at least one of elements of In, Ga, Sn, and Zn.

12. The semiconductor device according to claim 6, wherein the metal layer contains at least one of aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver and tantalum.