Packages for semiconductor die
AssigneeMicron Technology, Inc.
InventorsTodd O. Bolken, Cary J. Baerlocher, David J. Corisis, Chad A. Cobbley
Life of this patent
Estimating the term…
Abstract
A ball grid array assembly includes a package cover that encapsulates a die and a portion of a substrate to which the die is attached, including an edge of the substrate. Encapsulation of the substrate edge by the cover reduces penetration of moisture or other contaminants into the substrate. The cover includes a rib that extends to contact a circuit board to which the ball grid array assembly is connected. With such a rib, planarity between the circuit board and the substrate is maintained during soldering.
Claims39
A packaged semiconductor die, comprising:
- a substrate having a first major surface, a second major surface opposed to the first major surface, and a substrate edge extending between the first and second major surfaces, wherein the semiconductor die is mounted to the first major surface of the substrate;
- and
- an elongated rib that extends along at least a portion of the second major surface and which projects outwardly from the second major surface.
An integrated circuit assembly, comprising:
- a semiconductor die;
- a substrate to which the semiconductor die is attached and electrically connected;
- a circuit board;
- solder bumps that electrically connect the circuit board to the substrate;
- and
- a package cover that encapsulates the die, at least a portion of an edge of the substrate, and includes a rib that extends into contact with the circuit board.
A packaged die, comprising:
- a substrate having a first major surface to which the die is attached and a second major surface opposed to the first major surface;
- and
- a frame projecting outwardly from the second major surface, the frame surrounding a cavity bounded by the frame and the second major surface.
A package for a die that is mounted to a substrate, comprising an elongated rib situated to extend from a surface of the substrate and to encapsulate at least a portion of an edge of the substrate.
A mold for molding a package for at least one die bonded to a substrate, the mold defining a package cover for encapsulating the die and a portion of a surface of the substrate to which the die is bonded, and a rib that extends from a surface of the substrate.
A method of reducing moisture penetration into a circuit assembly, the circuit assembly including a substrate attached to a circuit board, comprising:
- covering at least a portion of an edge of the substrate with an encapsulant;
- and
- forming a rib that covers at least a portion of a first surface of the substrate and extends from a second surface of the substrate and contacts the circuit board.
A method of soldering a substrate provided with solder bumps to a circuit board, the method comprising:
- contacting the circuit board with the solder bumps;
- heating the solder bumps so that the solder bumps reflow to connect to the circuit board;
- and
- providing a rib situated to maintain a separation between the substrate and the circuit board as the solder bumps reflow.
A method of packaging a die, comprising:
- bonding the die to a first surface of a substrate;
- attaching one or more solder bumps to a second surface of the substrate;
- and
- providing an encapsulating layer that encapsulates the die and includes a rib that encapsulates at least a perimeter portion of the second surface of the substrate.
A method of attaching a substrate to a circuit board, comprising:
- providing a rib that covers a perimeter portion of a surface of a substrate;
- and
- electrically connecting the substrate to the circuit board so that the separation of the substrate and the circuit board is defined by the rib.
A method for attaching a ball grid array packaged die to a circuit board, comprising:
- providing a support band extending along at least a portion of a perimeter of a surface of the ball grid array packaged die;
- and
- heating the packaged device to reflow solder balls provided at the surface of the ball grid array packaged die.
A method of making a package for a die mounted to a substrate, comprising:
- contacting a first surface of the substrate with a first mold;
- contacting the first mold with a second mold;
- and
- injecting an encapsulant into a cavity defined by the first mold and the second mold, wherein one of the first mold and the second mold define a cavity for a rib.
Dependencies are inferred from the claim text.