Claims
- 1. A semiconductor article produced by a method which comprises providing a semiconductor device having aluminum containing contact pads; electrically attaching a leadframe to said contact pads; and applying sufficient zinc chromate in solution to said contact pads for a sufficient time and at a sufficient temperature to render said aluminum substantially resistant to corrosion from an atmosphere containing moisture and an ionic species.
- 2. The article of claim 1 wherein said zinc chromate in solution comprises an aqueous solution containing from about 0.1% to about 20% zinc chromate based on the weight of the solution component parts.
- 3. The article of claim 1 wherein said zinc chromate in solution comprises a saturated solution of zinc chromate in water.
- 4. The article of claim 1 wherein said application is conducted wherein said solution is maintained at a temperature of from about 50.degree. C. to bout 100.degree.C.
- 5. The article of claim 1 wherein said application is conducted for from about 10 to about 60 minutes.
- 6. The article of claim 1 wherein said aluminum containing contact pad is an alloy containing at least about 90% by weight aluminum.
- 7. The article of claim 6 wherein said alloy contains from about 0.5% to about 7% by weight copper.
- 8. The article of claim 6 wherein said alloy contains from about 0.5% to about 1% by weight silicon.
- 9. The article of claim 1 wherein said zinc chromate in solution comprises an aqueous solution containing from about 0.1% to about 20% zinc chromate based on the weight of the solution component parts; and wherein said application is conducted wherein said solution is maintained at a temperature of from bout 50.degree. C. to about 100.degree. C.; and wherein said application is conducted for from about 10 to bout 60 minutes.
- 10. A semiconductor article which comprises a semiconductor device having aluminum containing contact pads and a leadframe having leads which are electrically attached to a portion of said contact pads, the portion of the contact pads not underlying said leads having a surface which is the reaction product of aluminum and zinc chromate.
- 11. The article of claim 10 wherein said leadframe comprises aluminum and the outer surface of said leadframe comprises the reaction product of aluminum and zinc chromate.
- 12. The article of claim 10 wherein said aluminum containing contact pads comprise an alloy containing at least abut 90% by weight aluminum.
- 13. The article of claim 12 wherein said alloy contains from about 0.5% to about 7% by weight copper.
- 14. The article of claim 12 wherein said alloy contains from about 0.5% to about 1% by weight silicon.
Parent Case Info
This application is a division of application Ser. No. 07/065,344, filed Jun. 23, 1987 now U.S. Pat. No. 4,818,727.
US Referenced Citations (17)
Foreign Referenced Citations (4)
Number |
Date |
Country |
58-174436 |
Oct 1983 |
JPX |
60-131975 |
Jul 1985 |
JPX |
0131975 |
Jul 1985 |
JPX |
1532230 |
Nov 1978 |
GBX |
Non-Patent Literature Citations (1)
Entry |
Kirk-Othmer, Encyclopedia of Chemical Technology, 2nd edition, John Wiley and Sons, Inc. 1964, pp. 506-516. |
Divisions (1)
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Number |
Date |
Country |
Parent |
65344 |
Jun 1987 |
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