THIN FILM TRANSISTOR (TFT) HAVING COPPER ELECTRODES

• US 20120146018A1
• Filed: 08/25/2010
• Published: 06/14/2012
• Est. Priority Date: 08/26/2009
• Status: Active Grant

• Current Assignee: Heraeus Deutschland GmbH & Co. KG (Heraeus Holding GMBH)
• Original Assignee: Heraeus Materials Technology GmbH & Co. KG (Heraeus Holding GMBH)
• Inventors: Schlott, Martin, Schneider-Betz, Sabine
• Granted Patent: US 8,581,248 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A TFT structure is provided in which an oxidic semiconductor is used in combination with an electrode material based on a Cu alloy.

Claims

1-10. -10. (canceled)

11. A TFT structure comprising a semiconductor material and at least one electrode, wherein the semiconductor material is an oxidic semiconductor material, and wherein the at least one electrode comprises an electrode material based on a Cu alloy.

12. The TFT structure according to claim 11, wherein at least a source electrode and a drain electrode comprise the Cu alloy.

13. The TFT structure according to claim 11, wherein at least one alloying element of the Cu-based electrode material forms an oxidic intermediate layer at a boundary surface between the electrode material the and oxidic semiconductor material.

14. The TFT structure according to claim 11, wherein the structure is provided as bottom-gate or top-gate.

15. The TFT structure according to claim 11, wherein the oxidic semiconductor material comprises at least one oxide selected from indium oxide, zinc oxide, copper oxide, and mixed oxides based on at least one metal selected from indium, zinc, and copper.

16. The TFT structure according to claim 15, wherein the oxidic semiconductor material is selected from an In—

Ga—

Zn oxide, a Cu—

Cr oxide, and a Cu—

Al oxide.

17. The TFT structure according to claim 11, wherein at least one alloying element of the Cu alloy has a higher oxygen affinity than copper.

18. The TFT structure according to claim 11, wherein at least one alloying element of the Cu alloy has a higher oxygen affinity than at least one chemical element of the oxidic semiconductor material.

19. The TFT structure according to claim 11, wherein the Cu alloy contains at least one element selected from Mg, Mn, Ga, Li, Mo, and W, at a concentration of 0.1-10 at %.

20. The TFT structure according to claim 17, further comprising a pure Cu layer having a purity of at least 99.9% as a further electrode material, wherein the Cu alloy is applied as an intermediate layer over and/or under the pure Cu layer, and wherein the intermediate layer is thinner than the pure Cu layer.

21. The TFT structure according to claim 18, further comprising a pure Cu layer having a purity of at least 99.9% as a further electrode material, wherein the Cu alloy is applied as an intermediate layer over and/or under the pure Cu layer, and wherein the intermediate layer is thinner than the pure Cu layer.

22. The TFT structure according to claim 19, further comprising a pure Cu layer having a purity of at least 99.9% as a further electrode material, wherein the Cu alloy is applied as an intermediate layer over and/or under the pure Cu layer, and wherein the intermediate layer is thinner than the pure Cu layer.