Delphi Electronic Packaging—Overmold is a low cost electronic packaging technology whereby an entire circuitboard is overmolded with a special hard thermoset material providing a rugged and hermetically sealed environment for the board. The overmold can be applied as an underfill in flip chip applications and can encapsulate a heatsink and connectors. The overmold can be thermally sprayed with a metal to provide EMI shielding.

Delphi's innovative packaging technique incorporates recent advances in epoxy thermoset materials to package the entire electronic assembly. This electronic packaging concept consists of a PCB assembly populated with surface mount components adhesively mounted to a metal backplate, which is then overmolded to form the electronic enclosure. The surface mount components are fully encapsulated by the epoxy. Additionally, if there are flip chips mounted on the board they are simultaneously encapsulated and underfilled during the transfer molding process.

This packaging concept offers the potential for enhanced performance in the areas of mechanical protection, moisture protection, and shock and vibration resistance. The homogeneous material properties of the thermoset epoxy result in a lower, more uniform stress under the flip chip and better interconnection reliability. Furthermore, flip chip thermal management is improved by over two times when compared to traditional packaging technology and almost 100 times compared to a bare flip chip on a PCB.

A significant advantage is realized if the board has one or more flip chips, since these can be underfilled simultaneously during the overmolding process. For example, some electronic controllers may have 10 to 15 flip chips on one assembly. The traditional capillary underfill process is relatively slow and is performed one chip at a time. With Delphi's overmold process, underfill dispensing machines and long conveyer furnaces can be deleted from the manufacturing floor.

Potential Applications

Industry

Description

Electronics

- Provides cost-effective packaging and improved thermal management, ideal for rugged environments


Classification
Electronics