US 5,895,973 A · Electronic component assembly for maintaining component alignment during soldering

Abstract

An aligned electronic circuit component assembly for attaching components onto larger mounting members at predetermined positions thereon are provided. The mounting or heat spreader members include shift resistant regions which are disposed in close proximity or substantially aligned with peripheral portions or edges of the component die when the die is placed in its predetermined position on an associated mounting or base member. The shift resistant regions can include non-linear edge surfaces, such as the edge surfaces around notches in the members, so as to provide areas on the base or heat spreader member which do not have solder thereon. It has been found that the surface tension of the liquid solder during reflow acts to provide a restraining force at the edge surfaces so as to restrain the electronic component from shifting from the desired position on the base member. In addition, the notches are formed in a pattern around the base heat spreader member which keeps them to a minimum number so that the heat spreader is large enough to ensure proper heat dissipation from the circuit component while still restraining shifting of the component, either rotationally about an axis extending through the component or translationally across the layer of liquid solder. Accordingly, efficient high volume production of precisely aligned circuit component assemblies including component dies attached on base members at predetermined positions thereon can occur utilizing a solder reflow process.

Claims10

Dependent claims

An aligned electronic circuit component assembly comprising:

a die body for the electronic circuit component, the die body having a lower surface and peripheral edges thereof;
a base member to which the die body is to be attached at a predetermined position thereon, the base member having an upper surface larger than the lower surface of the die body;
a layer of substantially solid material between the die body lower surface and base member upper surface for being heated to a liquid state and solidifying to fix the die body to the base member in the predetermined position;
and
a predetermined number of notches formed in a periphery of the base member in close proximity to the die body peripheral edges with the die body in its predetermined position so that when the solid material is heated to form a layer of liquid between the die body and the base member, the surface tension of the liquid layer at said notches restrains the component against shifting from its predetermined position on the liquid layer, so that the component is attached to the base in the predetermined position when the liquid material hardens.

2 more elements

A power transistor assembly for an automotive ignition module, the power transistor assembly comprising:

a die body for a power transistor circuit component, the die body having a first predetermined size;
a heat spreader member for mounting the die body thereto and dissipating heat generated by use of the power transistor component, the heat spreader member having a second predetermined size larger than the die body first predetermined size;
a solder material between the die body and the heat spreader member which is heated to reflow the solder and form a layer of liquid solder for supporting the die body thereon and for attaching the die body to the heat spreader member when the liquid solder solidifies;
and
notches around the heat spreader member with peripheral portions of the die body being substantially aligned with the notches for resisting translational and rotational shifting of the floating die body on the liquid solder layer by the restraining force of the surface tension of the liquid solder at the notches to attach the die body to the heat spreader member at a predetermined position thereon when the solder solidifies.

2 more elements

Dependencies are inferred from the claim text.

Electronic component assembly for maintaining component alignment during soldering

Life of this patent

Electronic component assembly for maintaining component alignment during soldering

Life of this patent

Abstract

Claims10