Unisem (mauritius) Holdings Limited

Advanced Interconnect Technologies Limited

Texas Instruments Corporation

Shafidul Islam

Romarico Santos San Antonio

Anang Subagio

Michael H McKerreghan

Jerry B Medders

Daniel K Lau

Donald R Kelley

James A Kennon

Lenny Christina Gultom

Susan S Fitzgerald

Jeffrey L Popken

Edmunda G-o Litilit

Philip A Burr

A redistributed lead frame for use in a molded plastic semiconductor package is formed from an electrically conductive substrate by a sequential metal removal process. The process includes patterning a first side of the substrate to form an array of lands separated by channels; disposing a first molding compound within those channels; patterning a second side of the substrate to form an array of chip attach sites and routing circuits electrically interconnecting the array of lands and the array of chip attach sites; directly electrically interconnecting input/output pads on a semiconductor device to the chip attach sites; and encapsulating the semiconductor device, the array of chip attach sites and the routing circuits with a second molding compound. This process is particularly suited for the manufacture of chip scale packages and very thin packages.

Lead frame routed chip pads for semiconductor packages

A method for manufacturing a semiconductor device package including an electrically conductive lead frame having a plurality of posts disposed at a perimeter of the package. Each of the posts has a first contact surface at the first package face and a second contact surface at the second package face. The lead frame also includes a plurality of post extensions disposed at the second package face. Each of the post extensions includes a bond site formed on a surface of the post extension opposite the second package face. At least one I/O pad on the semiconductor device is electrically connected to the post extension at the bond site using wirebonding, tape automated bonding, or flip-chip methods. The package can be assembled using a lead frame having pre-formed leads, with or without taping, or using partially etched lead frames. A stack of the semiconductor device packages may be formed.

Reversible leadless package and methods of making and using same

A package () includes an integrated circuit device () having an electrically active surface () and an opposing backside surface (). A dielectric molding resin () at least partially encapsulates the integrated circuit die and the plurality of electrically conductive leads () with the backside surface () and the plurality of electrical contacts () being exposed on opposing sides of the package (). Features () are formed into electrically inactive portions of the integrated circuit die () to seal moisture paths and relieve packaging stress. The features () are formed by forming a trough () partially through the backside () of the wafer () in alignment with a saw street (), the trough () having a first width; and forming a channel () extending from the trough () to the electrically active face () to thereby singulate the integrated circuit device member, the channel () having a second width that is less than the first width.

Package having exposed integrated circuit device

A redistributed lead frame for use in a molded plastic semiconductor package () is formed from an electrically conductive substrate by a sequential metal removal process. The process includes: (a) patterning a first side of an electrically conductive substrate to form an array of lands separated by channels, (b) disposing a first molding compound () within these channels, (c) patterning a second side of the electrically conductive substrate to form an array of chip attach sites () and routing circuits () electrically interconnecting the array of lands and the array of chip attach sites (), (d) directly electrically interconnecting input/output pads on the at least one semiconductor device () to chip attach site members () of the array of chip attach sites (), and (e) encapsulating the at least one semiconductor device (), the array of chip attach sites () and the routing circuits () with a second molding compound (). This process is particularly suited for the manufacture of chip scale packages and very thin packages.

A redistributed lead frame for use in molded plastic semiconductor package () is formed from an electrically conductive substrate by a sequential metal removal process. The process includes: (a) patterning a first side of an electrically conductive substrate to form an array of lands separated by channels, (b) disposing a first molding compound () within these channels, (c) patterning a second side of the electrically conductive substrate to form an array of chip attach sites () and routing circuits () electrically interconnecting the array of lands and the array of chip attached sites (), (d) directly electrically interconnecting input/output pads on the at least one semiconductor device () to chip attach site members () of the array of chip attach sites (), and (e) encapsulating the at least one semiconductor device (), the array of chip attach sites () and the routing circuits () with a second molding compound (). This process is particularly suited for the manufacture of chip scale packages and very thin packages.

A semiconductor device package includes an electrically conductive lead frame having a plurality of posts disposed at a perimeter of the package. Each of the posts has a first contact surface disposed at the first package face and a second contact surface disposed at the second package face. The lead frame also includes a plurality of post extensions disposed at the second package face. Each of the post extensions includes a bond site formed on a surface of the post extension opposite the second package face. At least one I/O pad on the semiconductor device is electrically connected to the post extension at the bond site using wirebonding, tape automated bonding, or flip-chip methods. The package can be assembled using a lead frame having pre-formed leads, with or without taping, or using partially etched lead frames. A stack of the semiconductor device packages may be formed.

A method of making a lead frame and a partially patterned lead frame package with near-chip scale packaging (CSP) lead-counts is accomplished by performing a major portion of the manufacturing process steps with a partially patterned strip of metal formed into a web-like lead frame on one side, so that the web-like lead frame, which is solid and flat on the other side is also rigid mechanically and robust thermally to perform without distortion or deformation during the chip-attach and wire bond processes, both at the chip level and the package level. The bottom side of the metal lead frame is patterned to isolate the chip-pad and the wire bond contacts only after the front side, including the chip and wires, is encapsulated. The resultant package being electrically isolated enables strip testing and reliable singulation without having to cut into any additional metal.

Partially patterned lead frames and methods of making and using the same in semiconductor packaging

A lead frame () for a semiconductor device (die) package () is described. Each of the leads () in the lead frame () includes an interposer () having one end () disposed proximate the outer face () of the package () and another end () disposed proximate the die (). Extending from opposite ends of the interposer () are a board connecting post () and a support post (). A bond site () is formed on a surface of the interposer () opposite the support post (). Each of the leads () is electrically connected to an associated input/output (I/O) pad () on the die () via wirebonding, tape bonding, or flip-chip attachment to the bond site (). Where wirebonding is used, a wire electrically connecting the I/O pad () to the bond site () may be wedge bonded to both the I/O pad () and the bond site (). The support post () provides support to the end () of the interposer () during the bonding and coating processes.(FIG.).

Semiconductor device package and method for manufacturing same

A package () includes an integrated circuit device () having an electrically active surface () and an opposing backside surface (). A dielectric molding resin () at least partially encapsulates the integrated circuit die and the plurality of electrically conductive leads () with the backside surface () and the plurality of electrical contacts () being exposed on opposing sides of the package (). Features () are formed into electrically inactive portions of the integrated circuit die () to seal moisture paths and relieve packaging stress. The features () are formed by forming a trough () partially through the backside () of the wafer () in alignment with a saw street (), the trough () having a first width; and forming a channel () extending from the trough () to the electrically active face () to thereby singulate the integrated circuit device member, the channel () having a second width that is less than the first width. (Drawing)

The invention provides a taped lead frame for use in manufacturing electronic packages. The taped lead frame is composed of a tape and a lead frame formed from a plurality of individual metal features attached to the tape and arranged in a footprint pattern. The method of making the invention enables the thickness of conventional frames to shrink significantly to result in thinner packages for improved heat dissipation and shorter geometries for improved electrical performance. A plurality of such lead frames are arranged in an array on a sheet of tape and each lead frame is separated from surrounding lead frames by street regions on the tape such that no metal feature extends into a street region. Integrated circuit chips are attached and electrically connected to the lead frames and an encapsulant is applied, cured and dried over the lead frames and the street regions. Thereafter, the tape is removed and the lead frames are singulated by cutting through the encapsulant in the street regions to form individual packages. Singulation occurs in the street regions and does not cut into any metal feature forming the lead frame.

Taped lead frames and methods of making and using the same in semiconductor packaging

A semiconductor device package comprising a semiconductor device and an electrically conductive lead frame at least partially covered by a molding compound. The electrically conductive lead frame includes a plurality of leads disposed proximate a perimeter of the package and a die pad disposed in a central region formed by the plurality of leads. The die pad includes a first die pad surface disposed at the first package face, and a second die pad surface opposite the first die pad surface. The semiconductor device is attached to a central region of the second die pad surface, and a portion of the second die pad surface extending outward from the die is roughened to improve adhesion of the die pad to the molding compound. In other aspects, grooves are disposed in the first and/or second die pad surfaces to further promote adhesion of the die pad and to prevent moisture from permeating into the vicinity of the semiconductor chip. The die pad may further include tie bars extending therefrom, and at least one lip at may extend from a side surface of the die pad to anchor the die pad in the molding compound. The die pad may also include apertures disposed therein for allowing the egress of moisture from the package.

Die pad for semiconductor packages and methods of making and using same

A method of making a lead frame and a partially patterned lead frame package with near-chip scale packaging (CSP) lead-counts is accomplished by performing a major portion of the manufacturing process steps with a partially patterned strip of metal formed into a web-like lead frame on one side, so that the web-like lead frame, which is solid and flat on the other side is also rigid mechanically and robust thermally to perform without distortion or deformation during the chip-attach and wire bond processes, both the chip level and the package level. The bottom side of the metal lead frame is patterned to isolate the chip-pad and the wire bond contacts only after the front side, including the chip and wires, is encapsulated. The resultant package being electrically isolated enables strip testing and reliable singulation without having to cut into any additional metal.

A method of making a lead frame and a partially patterned lead frame package with near-chip scale packaging (CSP) lead-counts is accomplished by performing a major portion of the manufacturing process steps with a partially patterned strip of metal formed into a web-like lead frame on one side, so that the web-like lead frame, which is solid and flat on the other side is also rigid mechanically and robust thermally to perform without distortion or deformation during the chip-attach and wire bond processes, both at the chip level and the package level. The bottom side of the metal lead frame is patterned to isolate the chip-pad and the wire bond contacts only after the front side, including the chip and wires, is hermetically sealed with an encapsulant. The resultant package being electrically isolated enables strip testing and reliable singulation without having to cut into any additional metal.

A molding system and process is disclosed to interface with existing wire bonders using a single track design from the bonder through the molding process. During the molding operation, the bonded lead frame is transferred into the mold on a guide track system built into the mold chase. The mold closes and clamps the lead frame after which a compound charging system meters and injects a compound into the mold cavities. The mold is opened and the strip ejected and transferred out of the mold via internal guide tracks. A granular or pellet form of compound is use in the charging system.

Growing community of inventors

Plano, TX, United States of America

Shafidul Islam