US 2014/0151865 A1Published application

Semiconductor device packages providing enhanced exposed toe fillets

OwnerThomas H. Koschmiederinventor

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Abstract

A mechanism is provided by optically inspectable surface mount bonding of no-leads packages is enhanced. Embodiments of the present invention use a lead frame within the no-leads package that provides a plated surface not only along the bottom of the package but also in a direction substantially parallel to the sides of the package. Since the plated surface has a greater affinity for solder during a reflow process than does the bare metal of the lead frame, toe fillets have a greater chance of forming in a manner that can be optically inspected during a test for quality of the bonding of the package to a printed circuit board. In addition, a mold chase that conforms to the shape of the lead frame is used to prevent mold compound from adhering to the portions of the lead frame external to the package that are used as electrical contacts.

Claims15

Dependent claims

A semiconductor device package comprising:

a body formed from an encapsulant, wherein
the body comprises first and second major surfaces,
the body comprises at least one side surface coupling the first and second major surfaces, and
the first and second major surfaces are substantially parallel and at least a first portion of the side surface is substantially perpendicular to the first major surface and joins the first major surface at an edge of the body;
an electrical contact having a first exposed surface on the first major surface of the semiconductor device package body and a second exposed surface substantially parallel to the first portion of the at least one side surface, wherein
the first exposed surface and the second exposed surface of the electrical contact are connected at a first bend in the electrical contact,
the first exposed surface and the second exposed surface of the electrical contact are comprised of a solderable metal, and
the second exposed surface of the electrical contact is recessed from the first portion of the at least one side surface.

5 more elements

A method for forming a semiconductor device package, the method comprising:

providing a conductive metal lead frame, wherein the lead frame comprises
a die pad configured to mount a semiconductor device die,
a plurality of leads wherein each lead of the plurality of leads comprises
a first end and a second end wherein the first end is closer to the die pad than the second end,
a first length of the lead extending from the first end to a first bend wherein the first bend forms a first angle up from a plane formed by the die pad and the first length of the lead,
a second length of the lead extending from the first bend to a second bend wherein the second bend forms a second angle toward the plane formed by the die pad and the first length of the lead,
a third length of the lead extending from the second bend to a third bend wherein the third bend forms a third angle,
a fourth length of the lead extending from the third bend to the plane formed by the die pad and the first length of the lead, and
a fifth length of the lead extending from a fourth bend along the plane formed by the die pad and the first length of the lead wherein the fifth length of the lead and the fourth length of the lead are coupled at the fourth bend.

6 more elements

Dependencies are inferred from the claim text.