Folded frame carrier for MOSFET BGA
AssigneeFairchild Semiconductor Corporation
InventorsRuben P. Madrid, Marvin Gestole, Erwin Victor R. Cruz, Romel N. Madatad, Arniel Jaud, Paul Armand Calo
Life of this patent
Estimating the term…
Abstract
A folded frame carrier has a die attach pad (DAP) 30 and one or more folded edges 32, 33, 34, 35. Each folded edge has one or more studs 36 and each stud has a trapezoidal tip. The folded frame carrier may be made of single gauge copper or copper alloy. Multiple folded frame carriers may be formed between opposite rails of a lead frame. The folded edges are cut with a relief groove. The tips are formed in edges of the DAP and then the tips are folded upright. The tips provide electrical connection to the terminal on the rear surface of a power semiconductor mounted on the DAP.
Claims26
A method for packaging a semiconductor die comprising the steps of:
- providing a lead frame with a planar portion for receiving and holding the semiconductor die;
- forming one or more studs along a first edge of the planar portion of the lead frame;
- forming a groove in the surface of the planar portion disposed parallel to, and spaced apart from, the first edge;
- forming a tip with a four sided taper on the end of each of the one or more studs;
- bending the first edge around the groove to an angle with respect to the planar portion of the lead frame.
A flip chip packaged semiconductor device comprising:
- a die attach pad comprising a planar portion for receiving a semiconductor die;
- an adhesive or solder layer on the planar portion for holding a semiconductor die;
- a semiconductor die having one surface facing and attached to the planar portion of the die attach pad by the adhesive or solder;
- a wall along one edge of the die attach pad disposed transverse to the die attach pad;
- and
- a plurality of studs extending from the wall and spaced from each other;
- wherein the ends of the stubs have four sided trapezoidal tapered tips.
A flip chip packaged semiconductor device comprising:
- a die attach pad comprising a planar portion for receiving a semiconductor die and by one or more edges;
- an adhesive or solder layer on the planar portion for holding a semiconductor die;
- a semiconductor die having one surface attached to the planar portion of the die attach pad by adhesive or solder and another surface with bump or ball contacts;
- one or more walls, each wall along an edge of the die attach pad and disposed transverse to the die attach pad;
- and
- a plurality of spaced apart studs extending from each of the one or more walls;
- wherein the ends of each of the plurality of studs have a four sided trapezoidal tapered tip.
A method for packaging a semiconductor die comprising the steps of:
- providing a lead frame with a planar die attach pad for receiving and holding the semiconductor die;
- punching studs into one or more edges of the die attach pad to form one or more studs projecting from each punched edge;
- cutting a groove in the surface of the die attach pad proximate to each punched edge;
- and
- bending each punched edge about its respective cut groove in a direction toward the groove to dispose the punched edge with studs at an angle with respect to the die attach pad in two separate steps.
A method for packaging a semiconductor die comprising the steps of:
- providing a lead frame with a planar portion for receiving and holding the semiconductor die;
- forming studs along one edge of the planar portion of the lead frame;
- forming a groove in the surface of the planar portion disposed parallel to the edge with studs and spaced from the studs;
- bending the edge with studs around the groove to an angle with respect to the planar portion of the lead frame;
- and
- spanking the ends of the studs.
Dependencies are inferred from the claim text.