Semiconductor device and method for manufacturing the same

• US 8,541,781 B2
• Filed: 03/02/2012
• Issued: 09/24/2013
• Est. Priority Date: 03/10/2011
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Noda, Kosei
• Primary Examiner(s): Wilson, Allan R
• Assistant Examiner(s): Lau, Christine C
• Application Number:
  US13/410,604
• Publication Number:
  US 20120228605A1
• Time in Patent Office: 571 Days
• Field of Search: 257/43, 257/E29.273, 257/E29.277, 257/E29.28, 257/E29.29, 257/E29.293, 257/E29.296, 438/84, 438/104
• US Class Current: 257/43
• 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 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• 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
• CPC Class Codes: H10B 41/70 the floating gate being an electrode shared by two or more components

Abstract

A semiconductor device includes an oxide semiconductor film including a pair of first regions, a pair of second regions, and a third region; a pair of electrodes in contact with the oxide semiconductor film; a gate insulating film over the oxide semiconductor film; and a gate electrode provided between the pair of electrodes with the gate insulating film interposed therebetween. The pair of first regions overlap with the pair of electrodes, the third region overlaps with the gate electrode, and the pair of second regions are formed between the pair of first regions and the third region. The pair of second regions and the third region each contain nitrogen, phosphorus, or arsenic. The pair of second regions have a higher element concentration than the third region.

Claims

1. A semiconductor device comprising:

an oxide semiconductor film comprising a pair of first regions, a pair of second regions, and a third region;

a pair of electrodes in contact with the oxide semiconductor film and overlapping with the pair of first regions;

a gate insulating film over the oxide semiconductor film; and

a gate electrode overlapping with the third region with the gate insulating film interposed therebetween,

wherein the pair of second regions are provided between the pair of first regions and the third region,

wherein the pair of second regions comprise one or more elements selected from the group consisting of nitrogen, phosphorus, and arsenic,

wherein the third region comprises an element selected from the group consisting of nitrogen, phosphorus, and arsenic,

wherein a concentration of the one or more elements in the pair of second regions is higher than a concentration of the element in the third region, and

wherein a concentration of the one or more elements in the pair of the first regions is lower than the concentration of the one or more elements in the pair of the second regions.

2. The semiconductor device according to claim 1,

wherein the concentration of the one or more elements in the pair of second regions is higher than or equal to 5×

10²¹ atoms/cm³ and lower than 5×

10²² atoms/cm³, and

wherein the concentration of the element in the third region is higher than or equal to 5×

10²⁰ atoms/cm³ and lower than 5×

10²¹ atoms/cm³.

3. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises two or more elements selected from the group consisting of In, Ga, Sn, and Zn.

4. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises In, Ga, and Zn.

5. The semiconductor device according to claim 1, wherein the gate insulating film is provided over the pair of electrodes.

6. The semiconductor device according to claim 1, wherein a width of the pair of electrodes is smaller than a width of the oxide semiconductor film in a direction perpendicular to a channel direction.

7. The semiconductor device according to claim 1, wherein the pair of electrodes cover an end portion of the oxide semiconductor film.

8. The semiconductor device according to claim 1, wherein the pair of second regions and the third region comprise the same element selected from the group consisting of nitrogen, phosphorus, and arsenic.

9. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises a crystalline oxide semiconductor.

10. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises a crystalline oxide semiconductor with c-axis alignment.

11. A semiconductor device comprising:

an oxide semiconductor film comprising In, Ga, and Zn,

wherein the oxide semiconductor film comprises a channel region and a region in contact with the channel region,

wherein the channel region comprises nitrogen or phosphorus at a concentration of higher than or equal to 5×

10²⁰ atoms/cm³ and lower than 5×

10²¹ atoms/cm³,

wherein the region in contact with the channel region comprises nitrogen or phosphorus at a concentration of higher than or equal to 5×

10²¹ atoms/cm³ and lower than 5×

10²² atoms/cm³, and

wherein the channel region and the region in contact with the channel region comprise the same element selected from the group consisting of nitrogen and phosphorus.