Packaging electrical components

• US 5,778,526 A
• Filed: 05/05/1997
• Issued: 07/14/1998
• Est. Priority Date: 07/17/1992
• Status: Expired due to Term

• Current Assignee: VLT Incorporated (Vicor Corporation)
• Original Assignee: VLT Incorporated (Vicor Corporation)
• Inventors: Finnemore, Fred, Balog, John S., Vinciarelli, Patrizio, Johnson, Brant T.
• Primary Examiner(s): Arbes, Carl J.
• Application Number:
  US08/851,482
• Time in Patent Office: 435 Days
• Field of Search: 29/825, 29/840, 29/832, 29/830, 174/52.4
• US Class Current: 29/840
• CPC Class Codes: H01L 2224/05553 being rectangular
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 2224/49 of a plurality of wire connectors
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 25/072 the devices being arranged next to each other
• CPC Class Codes: H01L 25/162 the devices being mounted on two or more different substrates
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01027 Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/1306 : Field-effect transistor [FET]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H05K 5/0091 : Housing specially adapted for small components for resistors H01C; for capacitors H01G; for integrated circuits H01L23/00
• CPC Class Codes: H05K 7/20463 : Filling compound, e.g. potted resin
• CPC Class Codes: Y10T 29/49126 : Assembling bases
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49149 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49151 : by deforming or shaping

Abstract

A package for electrical components in which a circuit board holds the components, includes an enclosure having generally parallel, spaced apart upper and lower internal surfaces. The circuit board lies generally parallel to the lower internal surface with the electrical components held in an internal space between the circuit board and the upper internal surface. Conductive terminal pins extend from outside the enclosure into the internal space and are connected to the circuit board by conductive links, each link having an end attached to the periphery of the circuit board and another end projecting into the internal spaces. In other aspects, a resilient non-compressive encapsulant is used to fill a space within the package; an electronic component is mounted with a power-dissipating device sitting in the aperture of a circuit board, a power-dissipating surface in contact with a baseplate, and contact pads electrically connected to a circuit board; terminal pins are connected to a circuit board using a fence connected at the periphery of the circuit board, the fence extending substantially perpendicularly to the circuit board, the fence comprising at least two conductive links joined by a severable junction.

Claims

1. A method for mounting a power-dissipating component having contact pads comprising

mounting the component on a thermally conductive baseplate,

placing a circuit board having an aperture over the component with at least part of the power-dissipating component lying in the aperture, and

soldering the pads to the circuit board by heating the baseplate.

2. The method of claim 1 wherein the soldering comprises applying solder to the circuit board, pre-heating the circuit board to below the melting temperature of the solder, pre-heating the baseplate and the component to a temperature above the melting temperature of the solder, and placing the circuit board adjacent the component to cause the solder in the circuit board to melt.

3. The method of claim 1 wherein said step of mounting the component on a baseplate comprises

mounting the power-dissipating component on a substrate, and

mounting the substrate on the baseplate.

4. The method of claim 3 where said step of mounting the component on a baseplate further comprises

before mounting the power-dissipating component on the substrate, mounting the contact pads on the substrate, and

before mounting the substrate on the baseplate, connecting the contact pads to the power-dissipating component.

5. The method of claim 4 wherein the step of connecting comprises bonding wires to the pads and to the power-dissipating component.

6. The method of claim 1 further comprising forming a metal-lined through-hole in the circuit board at the site where the pads are to be soldered to the circuit board.

7. A method for mounting a power-dissipating component having contact pads comprising

mounting the component on a thermally conductive baseplate,

placing a circuit board having an aperture over the component with at least part of the power-dissipating component lying in the aperture, and

encapsulating a region comprising said aperture and a space between said circuit board and said baseplate surrounding said power-dissipating component.

8. The method of claim 7 further comprising the step of soldering the pads to the circuit board by heating the baseplate.

9. The method of claim 8 wherein the soldering comprises applying solder to the circuit board, pre-heating the circuit board to below the melting temperature of the solder, pre-heating the baseplate and the component to a temperature above the melting temperature of the solder, and placing the circuit board adjacent the component to cause the solder in the circuit board to melt.

10. The method of claim 9 wherein said step of mounting the component on a baseplate comprises

mounting the power-dissipating component on a substrate, and

mounting the substrate on the baseplate.

11. The method of claim 10 where said step of mounting the component on a baseplate further comprises

before mounting the power-dissipating component on the substrate, mounting the contact pads on the substrate, and

before mounting the substrate on the baseplate, connecting the contact pads to the power-dissipating component.

12. The method of claim 11 wherein the step of connecting comprises bonding wires to the pads and to the power-dissipating component.

13. The method of claim 9 further comprising forming a metal-lined through-hole in the circuit board at the site where the pads are to be soldered to the circuit board.

14. The method of claim 7 wherein said region extends laterally at least to the peripheral edges of said circuit board and vertically from said baseplate to a point above said circuit board.