Motorola Corporation

Other

Fred E Ostrem

Alfred G Ocken

Anthony J Polak

Rembert R Stokes

Charles Vandommelen

A method for constructing a feedthrough via connection and a corresponding apparatus includes a metallic plate (,), or rigidizer, preferably composed of an aluminum material. A solderable contact area (,), is located on the plate (,). This contact area (,) is preferable comprised of a copper material selectively disposed by a plasma spraying process. Next, an electrically insulating adhesive layer (,) is disposed onto the plate (,). This adhesive layer (,) has a feedthrough via (,) disposed therethrough aligned with the contact area (,). Then, a substrate (,), preferably composed of a flexible composite polyimide material, is disposed onto the adhesive layer (,). This flexible substrate (,) has a via (,) disposed therethrough with a solderable area (,) disposed thereon. Then, a quantity of solder (,) is disposed onto the solderable area (,), and the assembly (,) is heated so that the solder (,) flows into the vias (,) and (,), thereby providing an electrical connection including the solderable area (,) of the via (,), the solder (,), and the contact area (,). During this reflow step, the structure of the adhesive layer (,) acts as a soldermask preventing the solder (,) from flowing outside of an area defined by the via (,).

Feedthrough via connection on solder resistant layer

A method and structure for controlling solder height of a surface mount device on a substrate uses electrical connection pads (105, 105') disposed onto a substrate (101). A height control pad (111) is also disposed onto the substrate (101) positioned apart from the electrical connection pads (105, 105'). Solder fillets (107, 107', 113) are disposed onto both the electrical connection pads (105, 105') and the height control pad (111). A component (103) having an electrical termination portion (109, 109') in contact with the solder fillets (107, 107') associated with the electrical connection pads (105, 105 ') and a body portion (115) in contact with the solder fillet (113) associated with the height control pad (111). The resulting structure (100 has a height relationship (119) between the surface mount component (103) and the substrate (101) controlled principally by a quantity of solder in the electrically conductive solder fillet (113) is disposed onto the height control copper pad (111) and a geometry of the copper pads (105) and (105') and the height control copper pad (111).

Surface mount component height control

An electronic control module (10) includes a package substrate (12) having an interior cavity (28) through which a package lead (22) traverses. The interior cavity (28) is filled with an expandable polymer material (34). The expandable polymer material (34) is constrained within the cavity by a pressure resistive layer (32, 35) that overlies expandable polymer material (34) In one embodiment, an epoxy layer (32) forms an upper surface of the interior cavity (28). The expandable polymer material (34) is responsive to a fluid, such that upon contact with a fluid diffusing along the package lead (22), the expandable polymer material (34) will swell and form a fluid-tight pressure seal around the package lead (22). The fluid-tight pressure seal prevents the fluid from diffusing to interior portions of the electronic control module (10) and causing the failure of electronic components (18) mounted within the electronic module (10).

Electronic control module having fluid-tight seals of a polymer material

A component, preferably with a large mass like an electro-mechanical solenoid (101), includes a lead structure (109) to electrically terminate a winding (105) of the solenoid (101). The lead structure (109) is both rigid and flexible. The rigid portion of the lead structure includes an elongated first member (111 ) with a first inner end (113) connected to the winding (105) of the solenoid (101) and a first outer end (115). The flexible portion of the lead structure includes an elongated electrically conductive member (117) with a second inner end (119) connected to the winding (105) of the solenoid (101) and a second outer end (121). The second outer end (121) of the elongated electrically conductive member (117) is coupled to the first outer end (115) of the elongated first member (111). Preferably, the elongated electrically conductive member (117) has a cross-section smaller than a cross-section of the elongated first member (111).

Component with a ridgid and a flexible electrical termination

A method for constructing a feedthrough via connection and a corresponding apparatus includes a metallic plate (101), or rigidizer, preferably composed of an aluminum material. A solderable contact area (103), is located on the plate (101). This contact area (103) is preferable comprised of a copper material selectively disposed by a plasma spraying process. Next, an electrically insulating adhesive layer (105) is disposed onto the plate (101). This adhesive layer (105) has a feedthrough via (106) disposed therethrough aligned with the contact area (103). Then, a substrate (109), preferably composed of a flexible composite polyimide material, is disposed onto the adhesive layer (105). This flexible substrate (109) has a via (110) disposed therethrough with a solderable area (111) disposed thereon. Then, a quantity of solder (113) is disposed onto the solderable area (111), and the assembly (100) is heated so that the solder (113) flows into the vias (106) and (110), thereby providing an electrical connection including the solderable area (111) of the via (110), the solder (113), and the contact area (103). During this reflow step, the structure of the adhesive layer (105) acts as a soldermask preventing the solder (113) from flowing outside of an area defined by the via (106).

Feedthrough via connection

An electrical component/housing has a main body with a geometric central point and a lead frame having a plurality of leads formed of flat sheet stock. An intermediate flexible planar portion of each lead extends between emerging and end portions of each lead. The intermediate portion is orientated toward the central point so as to maximize absorption of thermal expansion stresses which are radially directed between the central point and the end lead portion which will be bonded to another structure. Also, a thermally stable connection arrangement comprising: a substrate having an electrical conductor thereon to which a component lead is connected at a third position, the substrate having a first coefficient of thermal expansion (a.sub.1); a heat sink base upon which the substrate is located at a first position, the base having a second predetermined coefficient of thermal expansion (a.sub.2); and a housing fixed to the base at a second position and having the lead extending therefrom to the electrical conductor to which it is soldered, the lead having a third predetermined coefficient of thermal expansion (a.sub.3). A first distance (l.sub.1) between the first position and the third position and a second distance (l.sub.2) between the first position and the second position being in the ratio (a.sub.2 -a.sub.3)/(a.sub.1 -a.sub.3) so that there is substantially no differential movement due to thermal expansion between the substrate and the component lead at the third position.

Electrical device having improved lead frame and thermally stable

In a substrate mounting assembly (10) critical bonding pads (20) adjacent one lateral edge (21) of a ceramic substrate (11) are connected to semiconductor die (13) via wires (26). The substrate and die are mounted on a aluminum base carrier plate (12) which serves as a heat sink for the semiconductor die. A relatively rigid first adhesive (40) is applied in one area between the substrate and base carrier so as to effectively fix one lateral edge (21) of the substrate and the critical bonding pads (20) with respect to the base carrier, while a second adhesive (41), comprising an acrylic adhesive tape, bonds other areas of the ceramic substrate to the base carrier. At a lateral edge (23) of the substrate opposite to the lateral edge (21) adjacent the critical bonding pads, additional bonding pads (22) are provided and wires/conductors (27) connect these additional bonding pads to lead frame projections (28) from a non-conductive housing (29) fixed to the aluminum base carrier. This configuration insures sufficient mechanical support for the ceramic substrate while also providing minimal stress for the wires connecting the semiconductor die to the critical bonding pads.

Growing community of inventors

Long Grove, IL, United States of America

Fred E Ostrem