Motorola Corporation

Barry C Johnson

Vincent J Pellechia

William H Lytle

John W Stafford

Ravinder K Sharma

Curtis W Mitchell

Ravichandran Subrahmanyan

Lubomir Cergel

An electrical contact and method for making an electrical contact allows a flat contact (404) to be formed early in the process of making an electronic device. The flat contact (404) is level with the remainder of the substrate (116) in which it is formed. The flat contact (404) does not interfere with any required subsequent process steps. The flat contact can be reflowed to form a ball contact (302) which protrudes above the top of the substrate (120) to which it is attached.

Electrical contact and method for making an electrical contact

A plurality of inserts (12) formed on a first substrate (11). A plurality of sockets (14) formed on a second substrate (13). Each socket of the plurality of sockets (14) on the second substrate (13) has a corresponding insert from the plurality of inserts (12) which physically aligns for coupling. At least one of the first (11) or second (13) substrates must be a semiconductor substrate. This arrangement allows for electrically connecting a semiconductor device or structure to another device for testing, burn-in, or final assembly.

Interconnect system for a semiconductor chip and a substrate

A one step metallization is disclosed for applying a layer of gold or gold alloy to the back of a silicon substrate to facilitate bonding that substrate to a metallized package member. The gold is applied to the substrate, for example by evaporation, while the substrate is maintained at a temperature between about 200.degree. C. and about 360.degree. C. Following the deposition the substrate is quickly cooled to room temperature. The thickness of the gold layer and the deposition temperature are adjusted to insure that the silicon diffusion profile is contained within the gold film during deposition. This insures good adhesion of the gold to the silicon substrate and provides a pure gold surface layer necessary for optimum bonding of the semiconductor substrate to a metallized package portion.

Gold metallization process

A brazing operation, using a silver-copper alloy preform in a temperature range of from 800.degree. C. to 1100.degree. C., is employed to attach either radial or axial conductive leads to ceramic non-linear resistors or capacitors, thereby eliminating the necessity of titanium-silver vacuum deposition or conductive cermet application prior to lead attachment. Glass encapsulation may be accomplished simultaneous with the brazing operation to further reduce cost.

Low cost assembly processes for non-linear resistors and ceramic

A low cost two step process for attaching conductive leads and heat dissipating elements and for encapsulating a ceramic non-linear resistor pellet is described. Low temperature soldering techniques are utilized to assemble the device. Low temperature soldering is made feasible by the treatment of the attaching surfaces of the pellet with a dilute solution of acid for reducing the oxide surface to a pure metal in preparation for soldering.

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Tempe, AZ, United States of America

Barry C Johnson