Thin film semiconductor material produced through reactive sputtering of zinc target using nitrogen gases

• US 7,927,713 B2
• Filed: 07/26/2007
• Issued: 04/19/2011
• Est. Priority Date: 04/27/2007
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ye, Yan
• Primary Examiner(s): Tarazano; D. Lawrence
• Assistant Examiner(s): Matzek; Matthew D
• Application Number:
  US11/829,037
• Publication Number:
  US 20080264777A1
• Time in Patent Office: 1,363 Days
• Field of Search: 257/43, 257/52, 257/63, 428/620
• US Class Current: 428/620
• CPC Class Codes: C23C 14/0036 Reactive sputtering
• CPC Class Codes: C23C 14/0676 Oxynitrides
• CPC Class Codes: H01L 21/02521 Materials
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/0257 Doping during depositing
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 27/016 Thin-film circuits
• CPC Class Codes: H01L 29/22 including, apart from doping materials or other impurities, only AIIBVI compounds
• 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: Y10T 428/12528 Semiconductor component

Abstract

The present invention generally comprises a semiconductor film and the reactive sputtering process used to deposit the semiconductor film. The sputtering target may comprise pure zinc (i.e., 99.995 atomic percent or greater), which may be doped with aluminum (about 1 atomic percent to about 20 atomic percent) or other doping metals. The zinc target may be reactively sputtered by introducing nitrogen and oxygen to the chamber. The amount of nitrogen may be significantly greater than the amount of oxygen and argon gas. The amount of oxygen may be based upon a turning point of the film structure, the film transmittance, a DC voltage change, or the film conductivity based upon measurements obtained from deposition without the nitrogen containing gas. The reactive sputtering may occur at temperatures from about room temperature up to several hundred degrees Celsius. After deposition, the semiconductor film may be annealed to further improve the film mobility.

Claims

1. An amorphous semiconductor film, formed by reactive sputtering, comprising a ternary compound of zinc, oxygen, and nitrogen.

2. The semiconductor film of claim 1, wherein the film has a sheet resistance of between about 100 ohm/sq to about 1×

10⁷ ohm/sq.

3. The semiconductor film of claim 1, wherein the film has a resistivity of between about 0.001 to about 30 ohm-cm.

4. The semiconductor film of claim 1, wherein the film has a mobility of greater than about 30 cm²/V-s.

5. The semiconductor film of claim 4, wherein the film has a mobility of greater than about 90 cm²/V-s

6. The semiconductor film of claim 1, wherein the film has a transmittance of up to about 80 percent.

7. The semiconductor film of claim 1, wherein the film has a graded band gap energy between about 3.1 eV and about 1.2 eV.

8. The semiconductor film of claim 1, wherein the compound comprises ZnN_xO_y.

9. The semiconductor film of claim 8, wherein the compound comprises a dopant.

10. The semiconductor film of claim 9, wherein the dopant comprises aluminum.

11. The semiconductor film of claim 10, wherein the film has a sheet resistance of between about 100 ohm/sq to about 1×

10⁷ ohm/sq.

12. The semiconductor film of claim 8, wherein the film has a resistivity of between about 0.001 to about 30 ohm-cm.

13. The semiconductor film of claim 8, wherein the film has a mobility of greater than about 30 cm²/V-s.

14. The semiconductor film of claim 13, wherein the film has a mobility of greater than about 90 cm²/V-s.

15. The semiconductor film of claim 8, wherein the film has a transmittance of up to about 80 percent.

16. The semiconductor film of claim 8, wherein the film has a graded band gap energy between about 3.1 eV and about 1.2 eV.