Electronic circuit apparatus and method of manufacturing the same

• US 20040212965A1
• Filed: 03/17/2004
• Published: 10/28/2004
• Est. Priority Date: 03/17/2003
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Matsushita, Akira, Tsuyuno, Nobutake, Masuda, Mitsuhiro, Ishii, Toshiaki, Urushiwara, Noriyoshi
• Application Number:
  US10/801,697
• Publication Number:
  US 20040212965A1
• Time in Patent Office: Days
• US Class Current: 361/709
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• CPC Class Codes: H01L 23/49531 the additional leads being a wiring board
• CPC Class Codes: H01L 24/45 of an individual wire connector
• 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 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/07811 Extrinsic, i.e. with electrical conductive fillers
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/10253 : Silicon [Si]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19107 : off-chip wires
• CPC Class Codes: H05K 1/0203 : Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/144 : Stacked arrangements of planar printed circuit boards
• CPC Class Codes: H05K 2201/043 : Stacked PCBs with their backs attached to each other without electrical connection
• CPC Class Codes: H05K 2201/10924 : Leads formed from a punched metal foil affixing a prefabricated self-supporting metal foil pattern H05K3/202
• CPC Class Codes: H05K 2203/049 : Wire bonding
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: H05K 5/0082 : specially adapted for transmission control units, e.g. gearbox controllers

Abstract

A resin-sealed electronic circuit apparatus capable of maintaining a high heat-dissipating property and packaging density in applications where high hermetic-sealing property and durability are required. The electronic circuit apparatus comprises at least two wiring circuit boards 12 and 13 on which electronic components are mounted. The wiring circuit boards 12 and 13 are fixed to a heat sink 14 having a high heat conductivity via an adhesive 9 and 10. The entirety of the wiring circuit boards 12 and 13 and heat sink 14, as well as a part of an external connection terminal 8 are hermetically sealed and integrally molded by a thermosetting resin composition 7. The electronic circuit apparatus is small and highly reliable and can be provided at low cost.

Claims

1. A electronic circuit apparatus comprising:

at least two wiring circuit boards each of which is mounted with at least two electronic components;

a heat sink on which said wiring circuit boards are fixed, said heat sink having a higher heat conductivity than that of said wiring circuit boards;

an external connection terminal electrically connected to said wiring circuit boards; and

a thermosetting resin composition with which the entire surfaces of said wiring circuit boards, a part of said heat sink and a part of said external connection terminal are integrally molded, wherein;

said wiring circuit boards on which all necessary electronic components are mounted in advance are fixed to the top and bottom of said heat sink via an adhesive layer.

2. The electronic circuit apparatus according to claim 1, wherein all of the electronic components mounted on one of said wiring circuit board are mounted by bonding bare chip components with a wire, and wherein all of the electronic components mounted on the other wiring circuit board are mounted by soldering.

3. The electronic circuit apparatus according to claim 1, wherein a wire bonding between said electronic components and said wiring circuit boards, a wire bonding between said wiring circuit boards, and a wire bonding between said wiring circuit boards and said external connection terminal are effected only towards one side of said heat sink.

7. The electronic circuit apparatus according to claim 1, wherein a part of a passage for circulating a cooling medium is formed in an external layer of said electronic circuit apparatus.

12. The electronic circuit apparatus according to claim 1, wherein said adhesive layer is formed by a two color printing process employing a heat-conducting paste containing a highly heat-conductive metal particle and/or a metal oxide particle, and an insulating organic paste, and wherein said heat-conductive paste is disposed immediately below where a bare silicon chip is mounted on said wiring circuit boards.

13. The electronic circuit apparatus according to claim 1, wherein said heat sink is made of a metal compound with electrical conductivity, and wherein said adhesive layer is formed by an insulating organic paste.

14. The electronic circuit apparatus according to claim 13, wherein said heat sink is made of a clad material containing a copper alloy or copper.

15. The electronic circuit apparatus according to claim 13, wherein said adhesive layer is made of a thermosetting resin composition containing an epoxy resin and an inorganic filler.

16. The electronic circuit apparatus according to claim 1, wherein at least one of said wiring circuit boards is a ceramic substrate.

17. The electronic circuit apparatus according to claim 1, wherein at least one of said wiring circuit boards is a flexible polyimide wiring circuit board.

4. A method of manufacturing an electronic circuit apparatus comprising the steps of:

fixing at least two wiring circuit boards each of which is mounted with at least two electronic components to a heat sink having a higher heat conductivity than that of said wiring circuit boards;

electrically connecting an external connection terminal with said wiring circuit boards;

integrally molding the entire surfaces of said wiring circuit boards, a part of said heat sink and a part of said external connection terminal with a thermosetting resin composition, said method further comprising the step of;

fixing said wiring circuit boards on which said electronic components are mounted to the top and bottom of said heat sink via an adhesive layer.

5. The method of manufacturing an electronic circuit apparatus according to claim 4, wherein a wire bonding between said wiring circuit boards and a wire bonding between said wiring circuit boards and said external connection terminal are effected only towards one side of said heat sink.

6. An electronic circuit apparatus comprising:

a wiring circuit board on which at least two electronic components are mounted;

a heat sink to which said wiring circuit board is fixed, said heat sink having a higher heat conductivity than that of said wiring circuit board;

an external connection terminal electrically connected to said wiring circuit board; and

a thermosetting resin composition with which the entire surface of said wiring circuit board, at least a part of said heat sink and a part of said external connection terminal are integrally molded, wherein;

a part of a passage for circulating a cooling medium is formed in an external layer of said electronic circuit apparatus.

8. A structure for mounting said electronic circuit apparatus of claim 6, wherein said electronic circuit apparatus is fixed on the interior of an automatic transmission assembly of an automobile, and wherein said cooling medium is a transmission fluid.

9. A structure for mounting said electronic circuit apparatus of claim 6, wherein said electronic circuit apparatus is fixed on the interior of an engine compartment of an automobile, and wherein said cooling medium is an engine cooling water.

10. A structure for mounting said electronic circuit apparatus of claim 6, wherein said electronic circuit apparatus is fixed on the interior of an engine intake pipe of an automobile, and wherein said cooling medium is the air that passes in said engine intake pipe.

11. A structure for mounting said electronic circuit apparatus of claim 6, wherein at least two electronic circuit apparatuses are stacked on top of each other, and wherein said cooling medium is circulated in the stacked electronic circuit apparatuses.