TECHNICAL FIELD

The present disclosure is related to packaging of semiconductor devices and, more particularly, to a surface mount package for a semiconductor device.

BACKGROUND

A variety of semiconductor device packages provide support for a semiconductor die (e.g., an integrated circuit chip) and associated wire bonds, provide protection from the environment, and enable surface mounting of the semiconductor device to and interconnection with a printed circuit board (“PCB”), typically with solder joints. For purposes of high-volume, and low-cost production of semiconductor device packages (also referred to “packages”), a semiconductor industry practice is to etch or stamp a thin sheet of metal material to form a panel or strip which defines a leadframe. A single strip may be formed to include multiple two-dimensional (“2D”) arrays, with each such array including a plurality of leadframes in a particular pattern. In a semiconductor device package manufacturing process, a semiconductor die is mounted to a die attach pad and then wire bonded to leads of the leadframe. Then, an encapsulant material (encapsulant or molding compound) is applied to the strip so as to cover the semiconductor die, wire bonds, and portions of the leadframes.

Upon the hardening of the encapsulant material, the leadframes within the strip are cut apart or singulated for producing individual semiconductor device packages. Such singulation is typically accomplished via a sawing process. In a mechanical sawing process, a saw blade (or dicing blade) is advanced along “saw streets” that extend in prescribed patterns between the leadframes to separate the leadframes from one another.

To insure that every solder joint between the leads of a package and lands on the PCB has been fully wetted by solder, an option exists to visually inspect the solder connections. A “wettable flank” lead design allows for the solder to wick up the edge of the package for visual inspection because unlike traditional leaded components such as small outline integrated circuit (“SOIC”) and dual-in-line (“DIP”) packages, the solder joints of leadless packages such as quad flat no-lead (“QFN”) surface-mount packages are formed primarily underneath the package. In the wettable flank lead, an outer region of the leads is utilized to form a recess that is sized and configured to accommodate reflowing solder therein to enable a visual solder inspection after being mounted to a package substrate such as a PCB.

QFN surface mount technology produces dimensional and inspection limitations of the wettable flank (or wettable feature) of the leadframe on a multi-layer routable circuit arrangement in the QFN package. Based on the design and manufacturability of routable leadframes, the resultant structure of the wettable feature limits desired trace dimensions, potentially causing future reliability issues as a result of the difficulty of performing an inspection. There is also a potential for producing copper burrs during a singulation process that is used to separate individual leadframes from a plurality of leadframes during a manufacturing operation. Reduction or elimination of the copper burr during a singulation process is a frequent concern with QFN packaging.

A wettable feature lead when created using a plating process produces a curved edge and may result in insufficient dimensions in a step cut. This problem is inherent in its design and in the etching process of wettable feature manufacturability for multi-layer routable leadframe substrates or otherwise. There is no presently known alternative to this problem.

Accordingly, what is needed is a design for maintaining sufficient electrical isolation between adjacent wettable feature leads of a leadframe employable with surface mount packaging technology.

SUMMARY OF THE DISCLOSURE

These and other problems are generally solved or circumvented, and technical advantages are generally achieved, by advantageous embodiments of the present disclosure for a lead for a surface mount package for a semiconductor device, and the surface mount package employing the same. In one example, the lead includes a central segment with a first side and a second side, a first extension from a portion of the first side, and a second extension from a portion of the second side. The lead also includes a recess extending through a portion of the central segment, the first extension and the second extension.

The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated that the specific examples disclosed may be readily utilized as a basis for modifying or designing other structures or processes for carrying out the same purposes of the present disclosure. It should also be realized that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims.

