Module and method for fabricating the same

• US 20060272150A1
• Filed: 07/03/2003
• Published: 12/07/2006
• Est. Priority Date: 07/03/2003
• Status: Abandoned Application

• Current Assignee: Kaoru Uchiyama, Masahiko Asano, Masahiro Sasaki, Syuuji Eguchi
• Original Assignee: Kaoru Uchiyama, Masahiko Asano, Masahiro Sasaki, Syuuji Eguchi
• Inventors: Uchiyama, Kaoru, Eguchi, Syuuji, Asano, Masahiko, Sasaki, Masahiro
• Application Number:
  US10/563,333
• Publication Number:
  US 20060272150A1
• Time in Patent Office: Days
• US Class Current: 29/841
• CPC Class Codes: H05K 2201/0191 wherein the thickness of the dielectric plays an important role
• CPC Class Codes: H05K 2201/0209 Inorganic, non-metallic particles
• CPC Class Codes: H05K 2201/09072 Hole or recess under component or special relationship between hole and component
• CPC Class Codes: H05K 2201/10189 Non-printed connector
• CPC Class Codes: H05K 2201/10734 Ball grid array [BGA]; Bump grid array
• CPC Class Codes: H05K 2203/1316 Moulded encapsulation of mounted components
• 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 3/0064 onto a polymeric substrate
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: H05K 5/0034 having an overmolded housing covering the PCB
• CPC Class Codes: H05K 5/0082 specially adapted for transmission control units, e.g. gearbox controllers
• CPC Class Codes: H05K 5/065 sealed by encapsulation, e.g. waterproof resin forming an integral casing, injection moulding
• CPC Class Codes: H05K 7/20854 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20863 takes precedence
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49171 with encapsulating

Abstract

A module having a smaller size with enhanced reliability and productivity, and a method for fabricating the module. The module comprises a connector (6) having metal terminals for connection, and a circuit board (1) mounting electronic components. The connector (6) and the board (1) are connected to each other through metal leads (7). The surface of the connector (6) on the side being connected to the board, the metal leads 7, and the electronic components are sealed with the same thermosetting resin (9). The thermosetting resin (9) is in solid state at temperatures of 40° C. or below before curing, and the thickness of the thermosetting resin (9) sealing the electronic components is changed depending on the heights of the electronic components.

Claims

1. A module comprising a connector (6) having metal terminals for connection, and a circuit board (1) mounting electronic components (3A, 3B, 4), said connector and said board being connected to each other through metal leads (7), wherein:

(A) the surface of said connector (6) on the side being connected to said board, said metal leads (7), and said electronic components (3A, 3B, 4) are sealed with the same thermosetting resin (9),

(B) said thermosetting resin (9) is in solid state at temperatures of 40°

C. or below before curing, and

(C) the thickness of said thermosetting resin (9) sealing said electronic components is changed depending on the heights of said electronic components (3A, 3B, 4).

2. The module according to claim 1, wherein:

said thermosetting resin is an epoxy resin that contains inorganic fillers and is in solid state at temperatures of 40°

C. or below.

3. The module according to claim 1, wherein:

said thermosetting resin has the following resin physical properties after curing,

linear expansion coefficient;

8-25 ppm/°

C.,

modulus of elasticity;

8-30 GPa, and

glass transition temperature;

80-200°

C.

4. The module according to claim 1, wherein:

the glass transition temperature of said circuit board is 150°

C. or higher.

5. The module according to claim 1, wherein:

ends of said metal leads are inserted in through holes formed in said board and thereafter fixed by using a solder or a conductive adhesive.

6. The module according to claim 1, wherein:

said electronic components are electronic components including a ball grid array (BGA) (11) or a chip scale package (CSP) (13), and

a circuit board (1A) mounting said BGA or CSP has through holes (19) having diameters of 0.1 mm-10 mm and allowing said thermosetting resin to flow via said through holes.

7. The module according to claim 1, wherein:

said circuit board is a printed board, and

a metal base or a plastic composite (14, 17, 18) for heat radiation is disposed just under said printed board mounting a power semiconductor chip that generates heat.

8. The module according to claim 7, wherein:

said metal base or said plastic composite for heat radiation has a smaller area than said printed board.

9. The module according to claim 1, wherein:

a metal- or plastic-made jig for mounting said module in an automobile engine room or on an engine is disposed on a rear surface of said circuit board.

10. The module according to claim 1, wherein:

only the electronic-component mounting surface of said circuit board is sealed with said thermosetting resin, and an opposite surface of said circuit board is fixed to or disposed on a metal or plastic casing including said connector by sticking, adhesion or a mechanical manner.

11. The module according to claim 1, wherein:

a metal or plastic composite (20) is disposed on a surface opposite to said circuit board with said electronic components and said thermosetting resin sealing said electronic components interposed therebetween.

12. A module comprising a connector (6) having metal terminals for connection, and a circuit board (1) mounting electronic components, said connector and said board being connected to each other through metal leads (7), wherein:

(A) the surface of said connector on the side being connected to said board, said metal leads, and said electronic components are sealed with the same thermosetting resin,

(B) said thermosetting resin is in solid state at temperatures of 40°

C. or below before curing,

(C) the thickness of said thermosetting resin sealing said electronic components is changed depending on the heights of said electronic components, and

(D) said connector (6) is disposed perpendicularly to a surface of said board being covered with said thermosetting resin sealing said electronic components or disposed on a surface of said board on the side opposite to the surface covered with said thermosetting resin.

13. A method for fabricating a module in which a connector (6) having metal terminals for connection, a circuit board (1) mounting electronic components including a BGA or a CSP, and metal leads (7) connecting said connector and said board to each other are molded with a resin, the method comprising the steps of:

preparing one of a low-pressure transfer molding machine and a compression molding machine with molding pressure of 5-70 kg/cm² and molding temperature of 150-180°

C., or an injection molding machine with molding pressure of 20-100 kg/cm² and molding temperature of 150-180°

C.;

preparing thermosetting resin that is in solid state at temperatures of 40°

C. or below before curing;

sealing the surface of said connector on the side being connected to said board, said metal leads, and said electronic components with the same thermosetting resin by using one of said molding machines; and

changing the thickness of said thermosetting resin sealing said electronic components depending on the heights of said electronic components in said sealing step.

14. The method for fabricating a module according to claim 13, wherein:

said circuit board is fixed to or disposed on a metal or plastic casing by sticking or adhesion to which said connector is tentatively fixed in advance, and thereafter said electronic components and a connector portion are integrally molded with said thermosetting resin.