Browse Prior Art Database

SPACE EFFICIENT POWER DIE ASSEMBLY

IP.com Disclosure Number: IPCOM000007657D
Original Publication Date: 1996-May-01
Included in the Prior Art Database: 2002-Apr-11
Document File: 2 page(s) / 80K

Publishing Venue

Motorola

Related People

Graham Adams: AUTHOR

Abstract

The use of power devices causes a number of major design issues when trying to integrate them into the main layout. The need to often attach such power devices to heatsinks results in power devices being put round the outside of the substrate. This is often wasteful on space, and seldom is the best posi- tion electrically. In addition, the connection of power devices to the substrate can be messy, with pack- aged devices normally requiring wave soldering, and bare die requiring wire bonding on the main line.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 54% of the total text.

Page 1 of 2

MozylRoLA Technical Developments

SPACE EFFICIENT POWER DIE ASSEMBLY

by Graham Adams

BACKGROUND AND PROBLEM

  The use of power devices causes a number of major design issues when trying to integrate them into the main layout. The need to often attach such power devices to heatsinks results in power devices being put round the outside of the substrate. This is often wasteful on space, and seldom is the best posi- tion electrically. In addition, the connection of power devices to the substrate can be messy, with pack- aged devices normally requiring wave soldering, and bare die requiring wire bonding on the main line.

  A need therefore exists for a method ofintegrat- ing the power devices to any position on the sub- strate, whilst maintaining good heatsinking, and standard reflow soldering for attachment to the substrate.

  The closest technology is the attachment of bare die to ceramic substrates with wire bonding on to the main substrate. However, this still has all the problems described above.

SOLUTION

  The invention relates to mounting a Kuramic substrate (I) underneath the main substrate (2), on which is mounted circuitry, as shown in Figure 1.

The Kuramic substrate (1) comprises a ceramic sub- strate having opposite sides coated with copper which is then etched. The baseplate (3) of the housing is formed so as to accommodate the Kuramic substrate
(1) underneath the main substrate (2). Accurate loca- tion ofthe Kuramic substrate (1) with respect to the baseplate (3)...