Motorola Corporation

Robert F Darveaux

Kingshuk Banerji

Anthony B Suppelsa

Julio A Abdala

Anthony J Suppelsa

Henry F Liebman

Francisco Da Costa Alves

Thomas A Goodwin

Francisco D Alves

Michael L Weiss

A discrete element electronic package (100) includes a heat spreader (180) with a cavity (185) for receiving a substrate (110), a substrate (110) mounted within the cavity (185) of the heat spreader (180), a heat-generating semiconductor device (170), such as a power transistor (170), mounted on the substrate (110), and electrical connectors (140) located on the substrate (110) to provide an electrical interface to the semiconductor device (170).

Discrete transitor assembly

A plastic leaded semiconductor package (20) has a semiconductor device (614) encapsulated in the package and mounted to a lead frame (612). The lead frame has a plurality of leads (622) that extend beyond the body (610) of the encapsulated package. Each of the plurality of leads is made from a metal having a predetermined coefficient of thermal expansion. A second metal (627) with a different coefficient of thermal expansion is disposed on at least one portion of each of the leads.

Leaded semiconductor package having temperature controlled lead length

A method for attaching a shield (102) to a an electronic assembly (116) having a heat sink (110) includes applying solder on the inner walls (104) of the shield (102). Next, the shield (102) is placed over the electronic assembly (116) such that the electronic assembly (116) is covered by the shield (102) and the shield (102) is in mechanical contact with the heat sink (110). Then, the shield (102) and heat sink (110) are heated so that the solder on the inner walls (104) of shield (102) flows and solders the shield (102) to the heat sink (110).

Method for attaching a shield

A method of attaching an integrated circuit (10) to a substrate (20) starts with electrically interconnecting (14) the integrated circuit on the substrate. Next, a bead of underfill material (22) is provided on the substrate (20) about the periphery (24) of the integrated circuit (10). At least a partial vacuum (34) is then applied to the integrated circuit (10) and the substrate (20) to substantially evacuate the area (18) between the integrated circuit (10) and the substrate (20). Finally, fluid pressure (42) is applied to the integrated circuit (10) and the substrate (20) to force at least a portion of the underfill material (22) into the area (18) between the integrated circuit (10) and the substrate (20).

Vacuum infiltration of underfill material for flip-chip devices

A method of soldering leadless components to a printed circuit board without using solder paste is disclosed. A thick layer of solder (42) is plated onto a printed circuit board (40), and an oxide layer (43) is formed by heating. Solder flux (45) is applied to those solder pads that are intended to be reflowed, and components (54) are placed. The printed circuit board is heated, and a solder joint (68) is effected between the components (54) and the circuit board (40), while the unfluxed solder pads (66) do not reflow and remain flat. Solder flux is then applied to the remaining solder pads (66) on the same or the opposite side of the circuit board. Additional components (77) are placed, and the circuit board (40) is reflowed a second time.

Growing community of inventors

Coral Springs, FL, United States of America

Robert F Darveaux