US 4,583,283 AGranted

Electrically isolated semiconductor power device

AssigneeMotorola, Inc.

InventorsJerry M. Dubois, Keith G. Spanjer

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Abstract

An improved power semiconductor device and manufacturing method are described wherein the external, thermally conducting, heat transfer face of the device is electrically insulated by a glassy dielectric which is intimately bonded directly to the conductive heat spreader supporting the semiconductor die. By forming the exposed corners of the heat spreader to be substantially smooth curved surfaces having a predetermined minimum radius of curvature greater than the thickness of the glassy dielectric, formation of a ridge of glass at the corners and edges of the heat spreader is avoided. For ease of assembly the piece parts are initially substantially flat and parallel. A molding compound of controlled shrinkage is used to avoid distorting the substantially flat smooth insulated heat transfer face which remains exposed in the encapsulated device.

Claims8

Dependent claims

A method for manufacturing an electrical device adapted to receive at least one semiconductor die, comprising:

forming a metallic heat spreader having a base portion with a first surface adapted to receive semiconductor die, a second surface opposite said first surface adapted to receive refractory dielectric coatings, and a side portion coupled to said first and second surfaces;
forming a base lead portion extending from said base portion of said metallic heat spreader;
shaping said metallic heat spreader so that said base portion has a first thickness and said base lead portion has a second thickness;
configuring said base lead portion so that it has a first extension portion ending in a first terminal portion;
creating a substantially smooth surface on said metallic heat spreader having a predetermined minimum radius of curvature and joining said side portion and said second surface;
coating said second surface and a portion of said substantially smooth curved surface with a refractory dielectric of predetermined thickness chemically bonded to said second surface, and said substantially smooth surface;
regulating said thickness of said refractory dielectric coating to be less than said predetermined minimum radius of curvature;
and
attaching to said first surface of said base portion, by electrically insulating means, at least one additional lead having a second extension portion ending in a second terminal portion.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/693,695Filed 22 Jan 1985 · division
Priority: 26 Mar 1982
Granted: 22 Apr 1986
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

G01N 29/0627
Synchronised with scanning, e.g. in real-time: cathode-ray tube displays
G01N 29/26
Details , e.g. general constructional or apparatus details: arrangements for orientation or scanning by relative movement of the head and the sensor
G01S 15/8931
Using a static transducer configuration: co-operating with moving reflectors
H10D 62/117
Shapes, relative sizes or dispositions of the regions of the semiconductor bodies; Shapes of the semiconductor bodies: shapes of semiconductor bodies