Electronic Device Installed in an Engine Room

• US 20080264165A1
• Filed: 01/23/2008
• Published: 10/30/2008
• Est. Priority Date: 01/25/2007
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Abe, Hiroyuki, Igarashi, Shinya
• Application Number:
  US12/018,658
• Publication Number:
  US 20080264165A1
• Time in Patent Office: Days
• US Class Current: 73/204.22
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 25/165 Containers
• CPC Class Codes: H01L 2924/00011 Not 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 2924/01012 Magnesium [Mg]
• CPC Class Codes: H01L 2924/0102 Calcium [Ca]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01077 Iridium [Ir]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01327 Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01L 2924/19043 being a resistor
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H05K 2201/0175 : Inorganic, non-metallic layer, e.g. resist or dielectric for printed capacitor
• CPC Class Codes: H05K 2201/0179 : Thin film deposited insulating layer, e.g. inorganic layer for printed capacitor
• CPC Class Codes: H05K 2203/1322 : Encapsulation comprising more than one layer
• CPC Class Codes: H05K 3/24 : Reinforcing the conductive pattern by solder coating H05K3/3457
• CPC Class Codes: H05K 3/244 : Finish plating of conductors, especially of copper conductors, e.g. for pads or lands selective plating methods H05K3/243; finish plating of conductors made by printing techniques H05K3/246; solder as finish H05K3/3457, e.g. by plating H05K3/3473
• CPC Class Codes: H05K 3/28 : Applying non-metallic protective coatings H05K3/0091 takes precedence; methods for intermediate insulating layers for build-up multilayer circuits H05K3/4673
• CPC Class Codes: H05K 3/3463 : Solder compositions in relation to features of the printed circuit board or the mounting process

Abstract

In an electronic device, which is to be installed in an engine room, that comprises a circuit board, electronic elements, which are carried by the circuit board and function when electricity is applied from the circuit board to them, a case that accommodates the circuit board on which the electronic elements are disposed, and a cover that covers an opening of the case, the entire surface of a conductor pattern formed of a conductive material on the circuit board is covered with a barrier metallic film made of a metal other than the metal of the conductive material having a property of mutual diffusion with a solder material, and the barrier metallic film is further covered with a protective insulating film.

Claims

1. An electronic device installed in an engine room comprising;

a circuit board,

an electronic element arranged on the circuit board and supplied with electric current from the circuit board,

a case that encases the circuit board, and

a cover that covers an opening of the case, wherein

the entire surface of a conductor pattern formed of a conductive material on the circuit board is covered with a metallic film made of a metal other than the metal of the conductive material having a property of mutual diffusion with a solder material.

2. The electronic device installed in an engine room according to claim 1, wherein

the metallic film is covered with a protective insulating film.

3. The electronic device installed in an engine room according to claim 2, wherein

the protective film is made of glass or an organic high molecular compound.

4. The electronic device installed in an engine room according to claim 1, wherein

the metallic film is made of a member selected from the group consisting of aluminum, nickel, tin, zinc, gold, platinum, titanium, palladium, chromium, iron, ruthenium, iridium, rhodium, alloys containing at least one of the chemical elements, and solder;

and

the thickness of the metallic film is 0.05-5 μ

m.

5. The electronic device installed in an engine room according to claim 1, wherein the conductor pattern is made of a member selected from the group consisting of gold, platinum, nickel, silver, alloys containing silver, and copper.

12. The electronic device installed in an engine room according to claim 1, wherein

the electronic device comprises a thermal-type flowmeter that measures a flow rate of a gas flowing in an intake tube of an internal-combustion device, and is installed in the intake tube.

6. An electronic device installed in an engine room comprising;

a circuit board,

an electronic element arranged on the circuit board and supplied with electric current from the circuit board,

a case that encases the circuit board, and

a cover that covers an opening of the case, wherein

the surface of a conductor pattern formed on the circuit board is covered with an oxide film or a nitride film.

7. The electronic device installed in an engine room according to claim 6, wherein

the surface of the conductor pattern to be soldered is covered with a metallic film made of a metal other than the metal of the conductive material having a property of mutual diffusion with a solder material, and

a conductor pattern surface not covered with the metallic film is covered with an oxide film or a nitride film.

8. The electronic device installed in an engine room according to claim 6, wherein

the electronic element is connected to the conductor pattern with a conductive adhesive, and

a conductor pattern surface to which the conductive adhesive is not applied is covered with an oxide film or a nitride film.

9. The electronic device installed in an engine room according to claim 6, wherein

the oxide film or the nitride film is covered with a protective insulating film.

10. The electronic device installed in an engine room according to claim 6, wherein

the oxide film is a member selected from the group consisting of silica, calcia, magnesia, alumina, and crystals having an ion bonding crystal structure.

11. The electronic device installed in an engine room according to claim 6, wherein

the nitride film is a nitride of aluminum, silicon, tungsten, molybdenum, or titanium.