|
Integrated circuit devices with solderable lead frame
| Details |
Inventors: Abys, Joseph A.; Kadija, Igor V.; Kudrak, Jr., Edward J.; Maisano, Jr., Joseph J.;
Assignee: AT&T Bell Laboratories (Murray Hill, NJ)
Primary Examiner: James; Andrew J.
Assistant Examiner: Whitehead, Jr.; Carl
Attorney, Agent or Firm: Alber; Oleg E.
A packaged device with a lead frame, a lead frame and an article of manufacture comprising a base metal, a layer of nickel on the base metal, and a protective composite of metal layers on the nickel. The composite includes, in succession from the nickel layer, a layer of palladium or soft gold strike, a layer of palladium-nickel alloy, a layer of palladium and a layer of gold. The palladium or soft gold strike layer acts primarily as a bonding (an adhesive) layer between the Ni and Pd-Ni alloy layers and as a layer that enhances reduction in porosity of subsequent layers, Pd-Ni alloy layer acts as a trap for base metal ions, Pd layer acts as a trap for Ni ions from the Pd-Ni alloy layer, and the outer gold layer synergistically enhances the quality to the Pd layer. The various layers are in thickness sufficient to effectively accomplish each of their designated roles, depending on the processing and use conditions. Pd on soft Au strike layer may be 1-5 microinches thick, Pd-Ni alloy layer from 4 to 100 microinches, Pd layer from 1 to 100 microinches and the outer gold layer from 1 to 100 microinches in thickness. |
|
DETAILED DESCRIPTION The present invention embodies a packaged device with a lead frame, a lead frame and an article of manufacture comprising a base metal, a layer of nickel on the base metal, and a protective composite of metal layers on the nickel.
The composite includes, in succession from the nickel layer, a layer of palladium or soft gold strike, a layer of palladium-nickel alloy, a layer of palladium and a layer of gold.
The palladium or soft gold strike layer acts primarily as a bonding (an adhesive) layer between the Ni and Pd-Ni alloy layers and as a layer that enhances reduction in porosity of subsequent layers, Pd-Ni alloy layer acts as a trap for base metal ions, Pd layer acts as a trap for Ni ions from the Pd-Ni alloy layer, and gold layer synergistically enhances the quality to the Pd layer.
The various layers are in thickness sufficient to effectively accomplished each of their designated roles.
depending on the processing and use conditions.
Pd or Au strike may be deposited in thickness from 1 to 5 microinches, Pd-Ni alloy from 4 to 100 microinches, Pd from 1 to 100 microinches and the outer gold layer from 1 to 100 microinches in thickness.
|
| Related patents |
|
|
Production method for integrated angular speed sensor device
In one aspect, the present invention provides a motion-sensing device that is a vibrating-type, integrated angular speed sensor and a production method that results in a ...
|
|
|
Photovoltaic cells for converting light energy to electric energy and photoelectric battery
It is a principal object of the present invention to reduce the shadowing area of the semiconductor wafer surface caused by the current collecting contacts and, thus, to ...
|
|
|
Electronic scale reduction technique
OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, this shows a sandwich-like assembly 10 of support sheet 11, flat spiral wire coil 12 and cover sheet 13. In this ...
|
|
|
Lightweight solar module and method of fabrication
The present invention is directed to an improved solar cell module, comprising a substrate and a first solar cell supported by the substrate, with the first solar cell ...
|
|
|
Solid state image sensing device
Accordingly, the object of the present invention is to provide a solid state image sensing device which can prevent the punch through from being generated during the ...
|
|
|
Device for one-sided etching of a semiconductor wafer
We claim: 1. An etching box type device for one-sided etching of a semiconductor wafer, said device comprising a trough-shaped basic body; a lid hermetically sealing ...
|
|
|
MEMS 
