Ultrathin leadframe BGA circuit package
AssigneeMicron Technology, Inc.
InventorsTeck Kheng Lee, Tan Yong Kian, Setho Sing Fee
Life of this patent
Estimating the term…
Abstract
A circuit package is formed using a leadframe. The leadframe is formed or etched to align a plurality of bond pad structures above a reference plane while supporting leadframe fingers are positioned below the reference plane. Jumper wires are wirebonded between terminals on the die and the bond pads to form a package subassembly. The subassembly is encapsulated and then background to remove the leadframe fingers and surrounding frame. The bond pads which remain embedded in the encapsulation material are exposed on the lower surface of the package for connection to further conductors.
Claims22
A method for forming an integrated circuit package:
- forming a leadframe with a plurality of bond pads supported by support members, the bond pads and support members formed from a single sheet of conductive material having a lower surface lying in a reference plane;
- positioning the portion of the support members distal of the bond pads below the reference plane;
- positioning a die adjacent some of the plurality of bond pads with the lower surface of the die lying above the reference plane;
- connecting at least one terminal on the die to at least one of the plurality of bond pads;
- encapsulating the die, bond pads and support members in an interstitial material;
- and
- removing the portion of the interstitial material and the portion of the support members distal to the bond pads to provide a lower surface for the package in which the lower faces of bond pads are exposed.
A method for forming an integrated circuit package, comprising:
- forming a leadframe having a frame member surrounding a space for receiving a semiconductor integrated circuit die, the frame member having a plurality of fingers projecting inwardly from the frame member in to the space, at least some of the fingers having bond pads at their inwardly extending ends, the bond pads being disposed around the space for receiving the circuit die;
- positioning a die in the space surrounded by the bond pads and connecting at least one of the bond pads to circuits on the die;
- offsetting the top surface of the frame member and substantially the entire length of at least one of the fingers to lie below the lower of the die and the surface of the bond pad members;
- encapsulating the assembly in interstitial material to form an oversized circuit package;
- and
- removing material from the lower surface of the oversized circuit package to define a package having a lower surface exposing the lower face of the bond pads while removing substantially the entire length of the fingers and the frame member.
A leadframe formed from a single sheet of material, comprising:
- a frame portion substantially surrounding an open portion;
- a plurality of fingers extending from the frame portion into the open portion;
- and
- a plurality of bond pads, each of the bond pads having an upper surface and a lower surface and positioned in the open portion supported by at least one of the fingers, the lower surface of one of the bond pads defining a reference plane beneath which lie the frame portion and the portions of the fingers adjacent the frame portion.
A leadframe formed from a single sheet of material, comprising:
- a frame portion substantially surrounding an open portion;
- a plurality of fingers extending from the frame portion into the open portion;
- a die pad positioned in the open portion;
- and
- a plurality of bond pads, each of the bond pads having an upper surface and a lower surface and positioned in the open portion supported by at least one of the fingers adjacent the die pad, the lower surface of one of the bond pads defining a reference plane beneath which lie the frame portion and the portions of the fingers adjacent the frame portion.
A package comprising:
- a die pad;
- a die mounted to the die pad;
- at least one bond pad positioned adjacent to the die pad;
- at least one lead connected between a die pad and a terminal on the die;
- encapsulating material surrounding the die, the die pad and all but an exposed face of at least one of the die pads to form a package.
An electronic system comprising:
- a die pad;
- a die mounted to the die pad;
- at least one bond pad positioned adjacent to the die pad;
- at least one lead connected between a die pad and a terminal on the die;
- encapsulating material surrounding the die, the die pad and all but an exposed face of at least one of the die pads to form a package;
- at least one solder ball is connected to the exposed face of at least one of the bondpads and a conductor in a printed circuit.
Dependencies are inferred from the claim text.