Method for transfer molding encapsulation of a semiconductor die with attached heat sink
First Claim
1. A method of packaging a semiconductor device assembly, comprising:
- forming a heat sink having a top surface and a bottom surface, each top and bottom surface having peripheral edges therearound and central portions thereof;
forming a protrusion at the peripheral edges of the bottom surface of the heat sink away from the central portion of the bottom surface of the heat sink;
positioning the top surface of the heat sink adjacent to a semiconductor device having a plurality of bond pads thereon; and
placing the heat sink and semiconductor device in a transfer molding apparatus with the protrusion formed at the peripheral edges of the bottom surface of the heat sink in contact with a portion of the transfer molding apparatus.
6 Assignments
0 Petitions
Accused Products
Abstract
A process for manufacturing semiconductor device including a heat sink adjacent to a die. A dam is positioned at the peripheral edges of the heat sink. During a transfer molding process, the dam serves two purposes. First, the dam prevents damage to the mold. Second, the dam prevents encapsulant packaging compound material from flowing onto the heat sink. The dam may be a gasket. The dam may also be a burr created by, for example, stamping the bottom of the heat sink. The dam may include copper, polyamides, and leadlock tape. The dam may be permanently connected to the heat sink or removed following packaging. The dam may be removed mechanically, through the use of heat, or during an electrolytic deflash cycle.
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Citations
15 Claims
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1. A method of packaging a semiconductor device assembly, comprising:
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forming a heat sink having a top surface and a bottom surface, each top and bottom surface having peripheral edges therearound and central portions thereof; forming a protrusion at the peripheral edges of the bottom surface of the heat sink away from the central portion of the bottom surface of the heat sink; positioning the top surface of the heat sink adjacent to a semiconductor device having a plurality of bond pads thereon; and placing the heat sink and semiconductor device in a transfer molding apparatus with the protrusion formed at the peripheral edges of the bottom surface of the heat sink in contact with a portion of the transfer molding apparatus. - View Dependent Claims (2, 3, 4, 5)
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6. A method of packaging a semiconductor device assembly, comprising:
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positioning a dam adjacent to surface of a heat sink away from a central portion of the surface of the sink; positioning the heat sink adjacent to a semiconductor device; and positioning the dam, heat sink, and semiconductor device in a transfer molding apparatus with the dam contacting a portion of transfer molding apparatus. - View Dependent Claims (7, 8, 9, 10)
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11. A method of packaging a semiconductor device assembly, comprising:
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providing a lead frame; positioning a dam adjacent to a surface of a heat sink, with edges of the dam positioned proximate peripheral edges of the surface and the dam positioned away from a central portion of the surface; positioning the heat sink adjacent to a semiconductor device; and positioning the lead frame, semiconductor device, heat sink, and dam in a transfer molding apparatus, the dam contacting a portion of the transfer molding apparatus. - View Dependent Claims (12, 13, 14, 15)
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Specification