Modification of the properties of metals

• US 4,690,715 A
• Filed: 06/18/1982
• Issued: 09/01/1987
• Est. Priority Date: 06/18/1982
• Status: Expired due to Term

• Current Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: American Telephone & Telegraph Company (AT&T, Inc.)
• Inventors: Nuzzo, Ralph G., Allara, David L.
• Primary Examiner(s): Morgenstern, Norman
• Assistant Examiner(s): Bell, Janyce A.
• Application Number:
  US06/389,775
• Time in Patent Office: 1,901 Days
• Field of Search: 427/304, 427/305, 427/255.4, 427/404, 427/405, 427/306, 427/250, 427/328, 427/327, 427/444, 427/302, 427/399, 427/409, 427/412.1, 148/6.15 R, 148/6.17, 148/6.24
• US Class Current: 148/252
• CPC Class Codes: C23C 22/02 using non-aqueous solutions
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02266 deposition by physical ablation of a target, e.g. sputtering, reactive sputtering, physical vapour deposition or pulsed laser deposition
• CPC Class Codes: H01L 21/02307 treatment by exposure to a liquid
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/312 Organic layers, e.g. photoresist H01L21/3105, H01L21/32 take precedence; photoresists per se G03C
• CPC Class Codes: H01L 21/321 After treatment
• CPC Class Codes: H05K 3/389 by the use of a coupling agent, e.g. silane

Abstract

The use of modifiers such as disulfides and phosphines is particularly effective in modifying the properties of metals such as noble metals and silver. For example, disulfides are useful for modifying the properties of gold and silver while phosphines are useful for metals such as platinum and palladium. Through treatment with a suitable modifier it is possible to change properties such as the wetting and adhesion properties of the treated metal. Additionally, the use of modifiers to treat a desired substrate enhances formation of continuous metal films on this substrate.

Claims

1. A process for fabricating a metal layer on a substrate comprising the steps of

(1) treating said substrate with a modifier, said modifier comprising a compound having (a) an organic functional group which interacts with the surface of said substrate to form a chemical bond and (b) a reactive moiety, and

(2) forming a layer of said metal on said treated substrate wherein said reactive moiety reacts with the species of said metal used in said formation.

2. The process of claim 1 wherein said reactive moiety includes N, P, O or S.

3. The process of claim 1 wherein said modifier comprises a disulfide.

4. The process of claim 3 wherein said modifier comprises trans-o-dithiane-4,5-diol.

5. The process of claim 1 wherein said modifier comprises a phosphine.

6. The process of claim 5 wherein said phosphine comprises ##STR10##

7. The process of claim 1 wherein the modifier is present on the substrate in a concentration in the range 10¹³ to 10¹⁵ molecules/cm².

8. The process of claim 1 wherein the surface of said substrate comprises a silicon oxide.

9. The process of claim 1 wherein the surface of said substrate comprises Al₂ O₃.

10. The process of claim 1 wherein said metal comprises a noble metal.

11. The process of claim 1 wherein said metal comprises a member of the group consisting of gold, silver, aluminum, platinum and palladium.

12. The process of claim 1 wherein said layer formation is by electroless plating.

13. The process of claim 1 wherein said modifier comprises an amine and said layer formation is accomplished by decomposition of an aluminum trialkyl at said substrate.

14. The process of claim 1 wherein said layer formation is accomplished using evaporation.

15. A process for modifying the properties of a noble metal containing surface comprising the steps of treating said surface with an organic modifier comprising (a) a reactive portion that reacts with said metal through a moiety containing a member of the group consisting of P and S, and (b) a moiety which provides said change of properties.

16. The process of claim 15 wherein said modifier comprises a disulfide.

17. The process of claim 16 wherein said modifier comprises trans-o-dithiane-4,5-diol.

18. The process of claim 15 wherein said modifier comprises a phosphine.

19. The process of claim 15 wherein said noble metal comprises a member of the group consisting of gold, platinum, palladium and silver.

20. The process of claim 15 wherein the modifier is present of the substrate in a concentration in the range 10¹³ to 10¹⁵ molecules/cm².

21. The process of claim 15 wherein said modifier changes the wetting properties of said noble metal.

22. The process of claim 15 wherein said metal comprises gold.